False Positives on Drug Tests

False Positives

What is a false positive? It is a test result that is returned when a substance tests positive for another compound. It is a case of mistaken identity. For example if you eat a couple poppy seed cakes before testing, you can get a positive result for opiates.

The chances of you getting a false positive depends on the quality of the laboratory that does the testing. There seems to be about 1,200 of these labs in the United States currently testing for drugs. Less than a 100 of these meet federal standards and most of the individual states do not regulate drug test labs. The number of false positives returned range from 4% to over 50%, depending on the lab.

A concern here is that, if your company tests for drug usage, they are probably not required to use a certified drug testing lab, which means you have a greater chance of getting a false positive.

The list below shows hundreds of products that AskDocWeb has been able to document as causes of a false positive drug test result.

Substances that may cause a false positive

A
4-Way Nasal Spray – false positive for Amphetamines, Morphine (Reference: 1)

Accutrim (PHENYLPROPANOLAMINE – Dexatrim) – false positive for Ecstasy (MDMA), Meth (References: 11, 16, 18)

Acetaminoph w/codeine – false positive for Morphine (Reference: 1)

Acet-AM (Theophylline Calcium Glycinate) – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Acro-Lase Plus® contains barbiturates (Reference: 18)

Adam (slang) – may test positive for methamphetamine and ecstasy (References:
33 and 52)

Afrinol (Pseudoephedrine) – may test positive for amphetamines (Reference: 33)

A.P.C. w/codeine – false positive for Morphine (Reference: 1)

A.R.M. – false positive for Amphetamines (References: 3 and 18)

Aciphex (rabeprazole sodium) – PPIs may test positive for THC (Reference: 37)

Actifed (pseudoephedrine and triprolidine) – false positive for Amphetamines (References: 3 and 18)

Actifed with Codeine Cough Syrup® – (Reference: 18)

Adderall – contains amphetamine, positive for Meth (References: Physician’s Desk Reference (PDR), 18, and 52)

Advil (Ibuprofen) – false positive for THC, Marijuana (References: 1, 14, 16, 18, 20, 26, and 29)

Afrin (Oxymetazoline Nasal Spray) – false positive for Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Aleve (Naproxen) – false positive for THC, Marijuana (References: 3, 16, and 18)

Alka-Seltzer Plus – false positive for Amphetamines, Morphine (Reference: 1)

Allerest – false positive for Amphetamines, Ecstasy, Meth and Morphine (References: 1, 3, 11, 16, and 18)

Allobarbital – may test positive for Barbiturates (References: 33 and 52)

Alphenol – may test positive for Barbiturates (References: 33 and 52)

Alprazolam – contains benzodiazepines (References: 18, 33, and 52)

Amantadine – may test false positive for amphetamines (References: 32 and 36 and 57)

Ambenyl – contains codeine (Reference: 18)

Amesec – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Amfepramone – false positive for Amphetamines, Ecstasy (MDMA), Meth (References: 3, 11, and 16)

Amifepramone – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Amineptine – false positive for Amphetamines and Ecstasy (References: 3, 11, and 18)

Amitriptyline (including the trade names Elavil, Lentizol, Tryptizol, Triptafen, Triptafen-M) – false positive for LSD (References: 3 and 47)

Amitriptyline – may test positive for Tricyclic Antidepressants (TCA) (References: 33 and 52)

Amobarbital – may test positive for barbiturates (References: 33 and 52)

Amogel PG® – contains opium/morphine (Reference: 18)

Amoxicillin – false positive for cocaine (References: 13, 16, 18, 20, 21, 26, and 29)

Ampicillin – false positive for cocaine (Reference: 29)

Amisulpride – may show false positive for opioids (Reference: 58)

Amphetaminil – metabolizes to amphetamine (Reference: 18)

Ampicin – may cause false positive for opiates (Reference: 20)

Amytal – Positive for Barbiturates (Reference: 52)

Anaprox – false positive for THC, Marijuana (References: 1, 3, and 18)

Ansaid – false positive for marijuana (Reference: 3)

Anti Anxiety medication, most – false positive for benzodiazepines (Reference: 3)

Anti Inflammatories – such as Naproxyn (Reference: 26)

Antiasthmatics that contain phenobarbitol – false positive for barbiturates (Reference: 3)

Antihistamines in general – false positives for Methadone (Reference: 43)

Antibiotics – false positives for Heroin, Cocaine (References: 13, 18, and 20)

Antrocol Elixor® – contains barbiturates (Reference: 18)

Anxitol – may test positive for Benzodiazepines (References: 33 and 52)

Apo-Naproxen – false positive for THC, Marijuana (Reference: 1)

Aprobarbital – may test positive for barbiturates (References: 33 and 52)

Artane – false positive for LSD (Reference: 3)

Ascriptin w/codeine – false positive for Morphine (Reference: 1)

Aspirin with Codeine – (Reference: 18)

Asthma medications – false positives for Amphetamines and Ecstasy (References: 20 and 21)

Astramoprh PF® – contains morphine (Reference: 18)

Ativan® (lorazepam) – contains benzodiazepines (References: 18 and 52)

Atripla (Efavirenz) – false positive for cannabinoid THC (Reference: 39)

Avelox (Fluoroquinolone) – false positive for opiates (Reference: 28)

B

B-2 vitamin – false positive for THC (Reference: 21)

Bactrim – may test positive for benzodiazepines (Reference: 60)

Barbital – may test positive for barbiturates (References: 33 and 52)

Bayer Select Maximum Strength Sinus Pain Relief Caplets – false positive for Amphetamines (References: 3 and 18)

Bayer Select Pain Relief Formula – false positive for THC, Marijuana (References: 3 and 18)

Benadryl (Diphenhydramine) – false positives for benzodiazepines, PCP, tricyclic antidepressants (Reference: 45)

Benadryl (Diphenhydramine) – false positives for PCP (Reference: 24, 62 and 65)

Bentyl® – false positive for LSD, Methadone (References: 3, 18, and 43)

Benylin – false positive for Opioids (Reference: 3)

Benzatropine/Artane® – (Reference: 18)

Benzedrine® – Amphetamines (Reference: 18)

Benzphetamine – false positives for Amphetamines, Ecstasy, and LSD (References: 3, 11, 18, and 47)

Biphetamine® – for Amphetamines (Reference: 18)

Black Pearls (Tung Sheuh pills) – contain benzodiazepines (Reference: 32)

Briantum – may test positive for benzodiazepines (References: 33, and 52)

Bromazepam (including the trade names Lexotan) – may test positive for benzodiazepines (References: 33 and 52)

Bromocriptine/Parlodel® – (Reference: 18)

Bromocription – false positive for LSD (Reference: 3)

Bromphenlramlne – false-Positive for Amphetamine (Reference: 22)

Broncholate CS – contains codeine (Reference: 18)

Bronkaid – false positive for Amphetamines, Heroin, Opiates, Ecstasy, Meth (References: 1, 3, 16, and 18)

Bronkotabs – false positive for Amphetamines, Heroin, Opiates (References: 1 and 11)

Buprenex® – contains synthetic opiates (Reference: 18)

Buprenorphine – contains synthetic opiates (Reference: 18)

bupivacaine – may test false positive for cocaine (Reference: 59)

Bupropion (Wellbutrin, Zyban) – false positive for Amphetamines (References: 12, 31, 32, 36, 57, 66, and 68)

Bupropion – may test false positive for MDMA (3,4-methylenedioxymethamphetamine ) (Reference: 67)

Bupropion – may test false positive for amphetamine and MDMA (Reference: 62)

Buproprion – false positive for LSD (Reference: 47)

Buspirone – false positive for LSD (Reference: 47)

Butabarbital (including the trade names Butisol and Soneryl) – may test positive for Barbiturates (References: 33, and 52)

Butalbital (including the trade names Fioricet and Fiorinal) – may test positive for Barbiturates (Reference: 33, 52)

Butisol – may test positive for Barbiturates (References: 33, and 52)

C

Cafergot® – false positive for LSD (References: 3, and 18)

Caldecon – false positive for Amphetamines, Morphine (Reference: 1)

Capital and Codeine Oral Solution – false positive for Opioids (References: 3, and 18)

Captagon® – metabolizes to amphetamine (Reference: 18)

Carbamazepine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46) Other brand names of Carbamazepine include Biston, Calepsin, Carbatrol, Equetro, Finlepsin, Sirtal, Stazepine, Telesmin, Tegretol, EPITAB XR(Pakistan) Teril, Timonil, Trimonil, Epimaz, Carbama/Carbamaze (New Zealand), Amizepin (Poland), Carzine (Kolkata), Mazetol, Tegrital, Tegrita (India), Karbapin (Serbia), Hermolepsin (Sweden), Degranol (South Africa), and Tegretal (Chile, Germany).

Cathne – false positives for Amphetamines, Meth and Ecstasy (MDMA) (References: 3, 11, and 16)

Centrax – may test positive for benzodiazepines (References: 33 and 52)

Cephradine – false positive for LSD (Reference: 47)

Cheracol – contains codeine (Reference: 18)

Cheracol Sinus – false positive for Amphetamines (Reference: 3)

Chinese herb pills – contain benzodiazepines (Reference: 32)

Chloroquine (Aralen®) – may test false positive for amphetamines (Reference: 36 and 57)

Chiorpromazlne – False-Positive for Amphetamine (References: 22 and 26)

Chlorazepate – Positive for Benzodiazepines (Reference: 52)

Chlordiazepoxide (Librium) – contains benzodiazepines (Reference: 18)

Chlordiazepoxide – may test positive for Benzodiazepines (References: 33 and 52)

Chlorpromazine (Thorazine) – false positive for Opiates (Also false for pregnancy) (References: 32, and 36)

Chlorpromazine (Thorazine) – may test false positive for PCP (l-phencyclohexylpiperidine, Phencyclidine) 33)

Chlorpromazine – false positive for phenylketonuria, amylase, uroporphyrins, urobilinogen. May also cause false positive pregnancy test. (Reference: 23)

Chlorpromazine – false positive for phencyclidine (Reference: 32)

Chlorpromazine – false positive for Tricyclic Antidepressants (TCA) and LSD (References: 46, and 47)

Chlorpromazine (Thorazine®) – may test false positive for amphetamines (References: 57)

Cipro (Fluoroquinolone antibiotic) – false positives for opiates (References:
25,
28, and
32)

Cipro XR (Fluoroquinolone) – false positive for opiates (Reference: 28)

Clinafloxacin – (Reference: 25)

Ciprofloxacin extended-release (Fluoroquinolone) – false positive for opiates (Reference: 28)

Ciprofloxacin (Fluoroquinolone) – false positive for opiates (Reference: 28)

Clinoril – false positive for THC, Marijuana (References: 3 and 18)

Clobazam (Frisium) – may test positive for Benzodiazepines (References: 33 and 52)

Clobenzorex – false positives for Amphetamines and Ecstasy (References: 3, 11, and 18)

Clonazepam – is a benzodiazepine (Reference: 18)

Clonazepam – may test positive for Benzodiazepines (Reference: 33, 52)

Clonopin – may test positive for Benzodiazepines (References: 33 and 52)

Clorazepate – may test positive for Benzodiazepines (Reference: 33)

Coca tea, Coca leaf, Coca flour, Coca oil – positive for cocaine (References: 41 and 42)

Co-codamol – positive for opiates (References: 33 and 52)

Codafen – positive for opiates (References: 33 and 52)

Codafen – may test positive for opiates (Reference: 33)

Codafen Continus – Positive for Opiates (Reference: 52)

Codeine – false positives for Amphetamines (Reference: 14 and 57)

Codeine – will test positive (not false) for opiates (Reference: 20)

Codeine Linctus – tests positive for opiates (References: 33 and 52)

Codeine Phosphate (Codafen Continus, Codeine Linctus, Pediatric BP, Galcodine, Kapake, Migraleve, Solpadol, Tylex) – tests positive for opiates (References: 33 and 52)

Codinal PH® – contains codeine (Reference: 18)

Co-dydramol – positive for opiates (References: 33 and 52)

Coffee-Break – false positive for Morphine (Reference: 1)

This product is no longer available in the USA or Canada.

Cold remedies with dextromethorphan – positive for opiates (heroin) (Reference: 21)

Comtrex – false positive for Opioids (Reference: 3)

Contac – false positive for Amphetamines, Morphine (References: 1 and 20)

Contac Severe Cold Formula – false positive for Morphine (Reference: 43)

Contact – false positives for Amphetamines, Meth and Ecstasy (References: 3, 11, 16, and 18)

Contact Non-Drowsy Formula Sinus Caplets – false positive for Amphetamines (References: 3 and 18)

Control – false positive for Morphine (References: 1)

Co-proximal – may test positive for Propoxyphene (PPX) (Reference: 33)

Coproximal – Positive for Propoxyphene (Reference: 52)

Cough medicines – See if any ingredients are on this list (Reference: 20)

Cough suppressants with Dextromethorphan (DXM) – false positive for Heroin (MDMA) (Reference: 16)

Cows head pills (Chinese herb) – contain benzodiazepines (Reference: 32)

Cramp End Tablets – false positive for THC, Marijuana (References: 3 and 18)

Cremacoat 4 – false positive for Morphine (Reference: 43)

Cyclimorph – positive for opiates (Reference: 33)

Cyclobenzaprine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

Cylert – false positives for Amphetamines and Ecstasy (References: 3 and 11)

Cyproheptadine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

D

Dalmane® – contains benzodiazepines (Reference: 18)

Darvocet – may test positive for Propoxyphene (PPX) (References: 33 and 52)

Darvon – may test positive for Propoxyphene (PPX) (Reference: 33)

Darvon® – contains synthetic opiates (Reference: 18)

Darvon – Positive for Propoxyphene (Reference: 52)

Datril – false positives for Marijuana (Reference: 1)

Daypro – false positives for benzodiazepines (Reference: 34)

Deconsal – contains codeine (Reference: 18)

Delorazepam (Briantum) – may test positive for benzodiazepines (References: 33 and 52)

Demerol – tests positive for opiates (References: 26 and 29)

Demetrin – may test positive for benzodiazepines (References: 33 and 52)

Deprenyl – false positives for Amphetamines and Ecstasy (References: 3, 11, and 18)

Desipramine – false positives for LSD (References: 32, 36, and 47)

Desipramine (Norpramine®) – may test false positive for amphetamines (References: 57)

Desoxyephedrine – false positive for Amphetamines and Ecstasy (References: 3, 11, and 18)

Desoxyn – may test positive for methamphetamine (Reference: 33)

Desoyn® – contains d-methamphetamine (Reference: 18)

Dexamphetamine Sulphate – Positive for Amphetamine (Reference: 52)

Dexatrim – false positive for Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Dexdenfluramine – false positive for Amphetamines and Ecstasy (References: 3, and 11)

Dexedrine – is an Amphetamine (References: 3, 11, and 18)

Dexedrine – may test positive for amphetamines (References: 33 and 52)

Dexfenfluramine – false positive for Amphetamines (References: 3)
and 11)

Dexlansoprazole – PPIs may test positive for THC (Reference: 37)

Dextroamphetamine – false positive for Amphetamines (Reference: 3 and 57)

Dextroamphetamine – may test positive for amphetamines (Reference: 33)

Dextromethorphan (DXM) – false positive for Heroin, Opiates, Morphine (References: 1, 3, 16, 21, 26, 29, and 32)

Dextromethorphan – may test false positive for PCP (References: 33)

Dextromethorphan hydrobromide or DXM – false positives for amphetamines (Reference:
11)

Dextropropoxyphene – may test positive for Propoxyphene (PPX) (References: 33, and 52)

DHC – may test positive for opiates (Reference: 33)

DHC Continus – Positive for Opiates (Reference: 52)

DHEA – false positive for anabolic steroid use (Reference: 13)

Diabetes – false positives for Amphetamines, Cocaine, THC, Ecstasy, Meth and Opiates (References: 3, 16, 20, and 21)

Diabismul® – contains opium/morphine (Reference: 18)

Diazemuls – may test positive for Benzodiazepines (Reference: 33)

Diazepam (Diazemuls, Stesolid, Valclair, Valium) – false positive for PCP (Reference: 29)

Diazepam (generic name for Valium) – contains benzodiazepines (Reference: 18, 20, 26)

Diazepam Diazemuls – Positive for Benzodiazepines (Reference: 52)

Diazepam – may test positive for Benzodiazepines (References: 33 and 52)

Dicyclomine – (Reference: 18)

Didrex – false positive for Amphetamines (Reference: 3, 11)

Didrex – metabolizes to methamphetamine and amphetamine (Reference: 18)

Diet aids with phenylpropanolamine (Dexatrim, Accutrim) – false positive for amphetamines (References: 10, 11, 16, and 18)

Dietac – false positive for Morphine (Reference: 1)

Dihydrocodeine (DHC Continus, Paramol, Remedeine, Remedeine Forte) – may test positive for opiates (Reference: 33, 52)

Dihyrocodeine – contains synthetic opiates (Reference: 18)

Dilantin – false positives for Barbiturates (References: 3 and 20)

Dilaudid – may test positive for opiates (References: 33 and 52)

Dilaudid® – contains synthetic opiates (Reference: 18)

Diltiazem – false positive for LSD (Reference: 47)

Dimetane-DC Cough Syrup ® – contains codeine (Reference: 18)

Dimetapp – false positive for Amphetamines (Reference: 3)

Dimetapp – false positive for Morphine, Meth, Ecstasy (References: 1, 11, 16, and 18)

Note: Dimetapp is a brand name of the generic drug loratadine, which is also sold under the brand names Claritin, Alavert, Claritin Reditab, Claritin Hives Relief, Clear-Atadine, Clear-Atadine Children’s, Loratadine Reditab, Ohm Allergy Relief, Tavist ND, Wal-itin, and Dimetapp ND.

Dimethylamphetamine – metabolizes to methamphetamine and amphetamine (Reference: 18)

Dimethylamylamine – false positive for amphetamines (Reference: 50)

Dinintel® – metabolizes to amphetamine (Reference: 18)

Diocalm – may test positive for opiates (References: 33 and 52)

Diphenhydramine – false positive for phencyclidine (Reference: 32)

Diphenhydramine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

Diphenhydramine (Benadryl) – false positive PCP results (Reference: 24)

DMAA (dimethylamylamine) – false positive for amphetamines (Reference: 50)

d-Methamphetamine – HCL may test positive for methamphetamine (Reference: 33)

Doco children’s cough syrup – false positive for Opioids (Reference: 3)

Dolobid – false positive for THC, Marijuana (References: 3 and 18)

Dolophine – may test positive for methadone (References: 33 and 52)

Dolophine® – contains synthetic opiates (Reference: 18)

Donnagel-PG ® – contains opium/morphine (Reference: 18)

Donnatal – may test positive for barbiturates (References: 33 and 52)

Donnatal® – contains barbiturates (Reference: 18)

Donnatol (for irritable bowel syndrome) – false positive for barbiturates (Reference:
3)

Dormonocet® – contains benzodiazepines (Reference: 18)

Doxepin – false positive for LSD (References: 36 and 47)

Doxepin – may test positive for Tricyclic Antidepressants (References: 33 and 52)

Doxylamine – false positive for phencyclidine, PCP, angel dust (Reference: 32)

Dristan Cold caplets – false positive for Amphetamines (Reference: 3)

Dristan Cough Formula – false positive for Heroin, Opiates, Morphine (References: 1 and 18)

Dristan Nasal Spray – false positive for Amphetamines (References: 26 and 29)

Drixoral Cold and Flu – false positive for Amphetamines (References: 3 and 18)

Dronabad® – (Reference: 18)

Dronabinol (Marinol) – shows positives for THC, marijuana (References: 16 and 18)

Duramorph – positive for opiates (Reference: 33)

Duramorph® – contains morphine (Reference: 18)

Durophet® – Amphetamines (Reference: 18)

E

E (slang) – may test positive for methamphetamine and ecstasy (References: 33 and 52)

Ecstasy (slang) – may test positive for methamphetamine and ecstasy (References: 33 and 52)

Edecrin – false positive for THC, Marijuana (References: 3 and 18)

Efavirenz – false positive for THC, Marijuana (References: 32, 39, and 52)

Efavirenz (Sustiva®) – may test positive for THC (Reference: 33, 57, and 60)

Effexor Tablets (venlafaxine hydrochloride) – false positive for PCP (Reference: 52)

Effexor XL – Potential Positive for PCP (Reference: 52)

Efidac/24 – false positive for Amphetamines (References: 3 and 18)

Efotamine – false positive for LSD (Reference: 3)

Elavil – false positives for opiates for up to three days, LSD, Methadone (Referencess: 3, 26, 29, and 43)

Elavil – Positive for Tricyclic Antidepressants (Reference: 52)

Eldepryl – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Elderpryl® – metabolizes to methamphetamine and amphetamine (Reference: 18)

Empirin w/codeine – false positive for Morphine, Opioids (References: 1, 3, and 20)

Emprin with Codeine® – (Reference: 18)

Enoxacin – false-positive for opiates (References: 25 and 28)

Entersan – may test positive for opiates (References: 33 and 52)

Ephedra – false positives for Amphetamines and Ecstasy (References: 20, 22, and 36)

Ephedrine – false positive for Amphetamines, Meth, and Ecstasy (References: 3, 11, 16, 18, 29, 32 and 57)

Ephedrine-based compounds – false positives for Amphetamines and Ecstasy (References: 20, 22, and 36)

Ephedrol, Ephedra (Ma Haung) – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Ergostat® – false positive for LSD (References: 3 and 18)

Ergotamine – (Reference: 18)

Esomeprazole – PPIs may test positive for THC (Reference: 37)

Estasule Minus – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Estazolam – may test positive for Benzodiazepines (References: 33 and 52)

Etafediabe – false positive for Amphetamines, Meth and Ecstasy (References: 3, 11, and 16)

Ethylamphetamine – metabolizes to amphetamine (Reference: 18)

Ethylmorphine – may test positive for opiates (References: 33 and 52)

Eve (slang) – may test positive for amphetamines (References: 33 and 52)

Excedrin IB – false positives for Marijuana (Cannabis) THC (References: 3, 16, and 18)

F

Factive (Fluoroquinolone) – false positive for opiates (Reference: 28)

Famprofazone – false positive for Amphetamines and Ecstasy (References: 3, 11, and 18)

Feldene – false positives for THC (References: 3 and 18)

Fencamine – metabolizes to methamphetamine and amphetamine (Reference: 18)

Fenelylline – false positive for Amphetamines and Ecstasy (References: 3, 11, and 18)

Fenfluramine – false positive for Ecstasy (References: 3 and 11)

Fenfluramine (Fen Phen) – may test false positive for amphetamines (References: 57)

Fenoprofin – false positive for Marijuana, Amphetamines, Barbiturates (Reference: 1)

Fenproporex – metabolizes to amphetamine (Reference: 18)

Fenproyorex – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Fentanyl – false positive for LSD (Reference: 47)

Finedal® – metabolizes to amphetamine (Reference: 18)

Fioricet – may test positive for Barbiturates (References: 33 and 52)

Fioricet with Codeine® – (Reference: 18)

Fiorinal – may test positive for Barbiturates (References: 33 and 52)

Fiorinal known to produce a false positive for phenobarbital (Reference: 61)

Fiorinal w/codeine – false positive for Morphine (References: 1, 3, 18, and 20)

Floxin (Fluoroquinolone) – false positive for opiates (Reference: 28)

Flunitrazepam – may test positive for Benzodiazepines (Reference: 33, 52)

Fluoroquinolone antibiotics – false positive for opiates (References: 28 and 32)

Fluoxetine (Prozac) – false positives for amphetamines and LSD (References: 31 and 47)

Flurazepam – contains benzodiazepines (Reference: 18)

Flurbiprofen – false positive for marijuana (Reference: 3)

Fluriprofen® – (Reference: 18)

Fluroquinolones (Levaquin®) – may test false positive for opiates (References: 57)

Fluspirilene – may test positive for amphetamines (Reference: 26)

Frisium – may test positive for Benzodiazepines (References: 33 and 52)

Furfenorex – metabolizes to methamphetamine and amphetamine (Reference: 18)

G

Galcodine – may test positive for opiates (References: 33 and 52)

Galenphol – may test positive for opiates (References: 33 and 52)

Gamanil – may test positive for Tricyclic Antidepressants (References: 33 and 52)

Gatifloxacin – (Reference: 25)

Gemifloxacin (Fluoroquinolone) – false positive for opiates (Reference: 28)

Genpril – false positive for THC, Marijuana (References: 3 and 18)

Gradumet® – contains d-methamphetamine (Reference: 18)

H

Halcion – Positive for Benzodiazepines (Reference: 52)

Haloperidol – false positive for LSD (Reference: 47)

Haltran – false positive for THC, Marijuana (References: 3 and 18)

Hamantashen – may test positive for opiates. (Reference: 13)

Hempseed Oil (Cannabis Seed/Hemp Oil) – false positive for THC (References: 3, 16, 21, 29, and 57)

Hold Cough Suppressant – false positive for Heroin, Opiates, Morphine (Reference: 1)

Homatropine Methylbromide – contains synthetic opiates (Reference: 18)

Hycodan® – contains synthetic opiates (Reference: 18)

Hydergine – false positive for LSD (Reference: 3)

Hydrocodone – false positive for oxycodone (Reference: 41 and 57)

Hydrocodone Bitartrate – contains synthetic opiates (Reference: 18)

Hydrocodone – contains synthetic opiates (Reference: 18)

Hydrocodone – may test positive for opiates (References: 33 and 52)

Hydromorphone (Dilaudid®) – contains synthetic opiates (Reference: 18)

Hydromorphone – may test positive for opiates (References: 33 and 52)

Hydromorphone (Dilaudid®) – may test false positive for oxycodone (References: 57)

Hydrostat – may test positive for opiates (References: 33 and 52)

Hydroymethamphetamone – false positive for Amphetamines (Reference: 3)

I

Ibuprin – false positive for marijuana (Reference: 3)

Ibuprofen – false positive for Marijuana (THC) (References: 1, 3, 16, 18, 29, and 48)

Ifenoprofen – false positive for THC, Marijuana (References: 3, 13, 18, 21, and 26)

Imitrex Hydergine® – may test false positive for LSD (Reference: 3, 18)

Indocin – false positive for THC, Marijuana (Reference: 3

Indocin – could affect urine drug test results (Reference: 18)

Infantol Pink ® – contains opium/morphine (Reference: 18)

Infumorf – contains morphine (Reference: 18)

Isoclor Expectorant – contains codeine (Reference: 18)

J

Joy detergent (now that’s weird) – false positives (Reference: 36)

K

Kaoden with Codeine® – (Reference: 18)

Kaodene with Paregoric® – contains opium/morphine (Reference: 18)

Kapake – may test positive for opiates (References: 33 and 52)

Kenesed® – contains barbiturates (Reference: 18)

Kapidex – PPIs may test positive for THC (Reference: 37)

Ketamine – false positive for PCP (References: 16 and 32)

Ketoprofen – false positive for THC (References: 3, 16, and 18)

Kidney disease – false positive for Cocaine (References: 3, 16, and 20)

Kidney infection – false positive for Amphetamines, THC, Ecstasy, and Opiates (References: 3, 16, and 21)

Klonopin – may test positive for Benzodiazepines (References: 33 and 52)

Klonopin® – contains benzodiazepines (Reference: 18)

Koalin and Morphine Mixture – may test positive for opiates (References: 33 and 52)

L

Labetolol – false positive for LSD (References: 36 and 47)

Lansoprazole – PPIs may test positive for THC (Reference: 37)

Lerisum – may test positive for Benzodiazepines (Reference: 33)

Ketipinor (quetiapine) – false-positives for amphetamines (Reference: 48)

Labetalol (Labetalol) – may test false positive for amphetamines (References: 57)

Lamotrigine (Lamictal®) – false positive for PCP (Reference: 53)

Lentizol – Positive for Tricyclic Antidepressants (Reference: 52)

Lerisum – Positive for Benzodiazepines (Reference: 52)

Levaquin® (Fluoroquinolone) – false positive for opiates (Reference: 28)

Levofloxacin (Fluoroquinolone antibiotic) – false positives for opiates (References: 25, 28, and 57)

Lexotan – may test positive for benzodiazepines (References: 33 and 52)

Libritab® – contains benzodiazepines (Reference: 18)

Librium – may test positive for Benzodiazepines (References: 33 and 52)

Librium® – contains benzodiazepines (Reference: 18)

Limbitrol® – contains benzodiazepines (Reference: 18)

Lisuride – false positive for LSD (Reference: 3)

Lisuride/Dopergin® – (Reference: 18)

Liver Disease – false positive for Opiates, Ecstasy, THC and Amphetamines (References: 3, 16, 20, and 21)

l-Methamphetamine HCL – may test positive for methamphetamine (Reference: 33)

Lodine – false positive for THC, Marijuana (References: 3, 18, and 20)

Lofepramine – may test positive for Tricyclic Antidepressants (References: 33 and 52)

Lomefloxacin – (Reference: 25)

Lomont – may test positive for Tricyclic Antidepressants (References: 33 and 52)

Loprazolam – contains benzodiazepines (Reference: 18)

Loratab – may test positive for opiates (References: 33 and 52)

loratadine (Dimetapp) – false positive for Amphetamines (Reference: 3)

Lorazepam – contains benzodiazepines (Reference: 18)

Lorazepam – may test positive for Benzodiazepines (References: 33 and 52)

Lorcet – may test positive for opiates (References: 33 and 52)

Lormetazepam – may test positive for Benzodiazepines (References: 33 and 52)

Lortab – an opioid analgesic (References: Physician’s Desk Reference (PDR))

Love Drug (slang) – may test positive for amphetamines (References: 33 and 52)

Luminal – may test positive for barbiturates (References: 33 and 52)

Luminal® – contains barbiturates (Reference: 18)

Lysergol – false positive for LSD (References: 3 and 18)

M

Ma Huang (Ephedra sinica) – false positives for Amphetamines and Ecstasy (References: 20, 32, and 36)

Marax – false positive for Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Margestic – false positive for Opioids (Reference: 3)

Marinol® – shows positive for Marijuana (THC) (References: 3 and 18)

Maximum Strength Sine-aid – false positive for Amphetamines (Reference: 3)

Maximum Strength Sinus Gelcaps – (Reference: 18)

Maximum Strength Sudafed Sinus – false positive for Amphetamines (Reference: 3)

Maximum Strength Tylenol Sinus gelcaps – false positive for Amphetamines (References: 3 and 18)

Meclomen – false positive for THC, Marijuana (References: 3, 18, and 52)

Medacepan – may test positive for Benzodiazepines (References: 33 and 52)

Medazepam – may test positive for Benzodiazepines (Reference: 33)

Medipren – false positive for THC, Marijuana (References: 3 and 18)

Mediprim – false positive for marijuana (Reference: 3)

Mefenorex – false positive for Amphetamines and Ecstasy (References: 3, 11, and 18)

Menstrual cramp medications – like Midol and Trendar (Reference: 26)

Meperidine – false positive for phencyclidine (Reference: 32)

Mephentermine – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Mesocarb – false positive for Meth and Ecstasy (References: 3, 11, 16, and 18)

Methadone – contains synthetic opiates (Reference: 18)

Methadone Hydrochloride – tests positive for methadone (Reference: 33)

Methadose – may test positive for methadone (Reference: 33, 52)

Methamprex – may test positive for methamphetamine (Reference: 33)

Methedrine – may test positive for methamphetamine (Reference: 33)

Methoxyphenamine – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Methphenidate – false positive for Amphetamines and Ecstasy (Reference: 11)

Methyldopa – may test positive for amphetamine (Not yet documented but see the post by Marcie)

Methylenedioxyamphetamine (MDA) – may test positive for amphetamines (Reference: 33)

Methylenedioxymethamphetamine (MDMA) – may test positive for methamphetamine and ecstasy (Reference: 33)

Methylphenidate (Ritalin) – an Amphetamine-like stimulant (References: 3 and 32)

Methysergide/Sansert® – (Reference: 18)

Methysergiside – false positive for LSD (Reference: 3)

Metoclopramide – false positive for LSD (Reference: 47)

Mexiletine (Mexitil®) – may test false positive for amphetamines (References: 57)

Midol – false positive for THC, Marijuana (References: 3, 18, 26, and 29)

Migraleve – may test positive for opiates (References: 33 and 52)

Mini-thins – false positives for Amphetamines and Ecstasy (Reference: 20)

Minocycline – can cause false positive results with certain urine tests. (Reference: 69)

Miracle herb pills (Chinese herb) – contain benzodiazepines (Reference: 32)

Mogadon – may test positive for benzodiazepines (References: 33 and 52)

Morax – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Morazone – false positive for Meth and Ecstasy (References: 3, 11, and 16)

Morcap – positive for opiates (Reference: 33)

Morphine Sulfate, including the trade names Astramorph, Cyclimorph, Duramorph, Morcap, MS Contin, Oramorph, Roxanol, and Severedol – positive for opiates (Reference: 33)

Motrin – false positive for THC, Marijuana (References: 1, 3, 16, 18, 20, 26, and 29)

Moxifloxacin (Fluoroquinolone) – false positive for opiates (References: 25 and 28)

MS Contin – positive for opiates (Reference: 33)

MS Contin Tablets® – contain morphine (Reference: 18)

MSIR® – contains morphine (Reference: 18)

Mudrane GC® – contains barbiturates (Reference: 18)

N

Naldecon – false positive for Morphine (1)

Nalfon – false positive for Marijuana, Amphetamines, Barbiturates, Benzodiazephines, Methaqualone (References: 1, 3, and 18)

Naprosyn – false positive for THC, Marijuana (References: 1, 3, and 18)

Naproxen (Aleve) – false positive for THC, Marijuana (References: 1, 3, 16, 21)

Naproxyn – (Reference: and 26)

Nasal sprays (Vicks inhaler, Afrin) – false positive for Amphetamines and Ecstasy (References: 10, 16, and 21)

Navonaprox – false positive for THC, Marijuana (Reference: 1)

Nembutal – may test positive for barbiturates (References: 33 and 52)

Nembutal Sodium – contains barbiturates (Reference: 18)

Neosynephren – false positive reading for Amphetamines (References: 26 and 29)

Neosynephrine – False positive for Amphetamines (References: 3, 18, and 26)

Nexium – PPIs may test positive for THC (Reference: 37)

Nitrazepam – may test positive for benzodiazepines (References: 33 and 52)

No Drowsiness Sinarest Tablets – (References: 3 and 18)

Nobritol – may test positive for Benzodiazepines (References: 33 and 52)

Nobrium – may test positive for Benzodiazepines (References: 33 and 52)

Noctamide – may test positive for Benzodiazepines (References: 33 and 52)

Nonprescription products that contain opium – (i.e., morphine) (Reference: 18)

Norcyclobenzaprine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

Norflex – false positive for Morphine (Reference: 43)

Norfloxacin (Fluoroquinolone) – false positive for opiates (References: 25 and 28)

Noroxin (Fluoroquinolone) – false positive for opiates (Reference: 28)

Novahistine DH® – contains codeine (Reference: 18)

Novahistine Expectorant® – contains codeine (Reference: 18)

Novocain – may test positive for Opiates (Reference: 52)

NSAIDS – false positive for THC, Marijuana (References: 3, 18, 20, and 32)

Nucofed Expectorant – contains codeine (Reference: 18)

Numorphan® – contains synthetic opiates (Reference: 18)

Nuprin – false positive for THC (References: 3, 16, 18, 20, 26, and 29)

Nyquil – false positive for Amphetamines, Heroin, Opiates, Morphine, Meth, Ecstasy, Methadone (References: 1, 3, 11, 14, 16, 18,20, 26, 29, and 43)

O

Obetrol® – Amphetamines (Reference: 18)

Ofloxacin (antibiotic) – false positives for opiates (References: 25 and 28)

Omeprazole – PPIs may test false positive for THC (Reference: 37)

Opazimes – may test positive for opiates (References: 33 and 52)

Oramorph – positive for opiates (Reference: 33)

Oramorph – contains morphine (Reference: 18)

Ornade – false positive for Amphetamines (References: 3 and 18)

Ortain – false positive for Amphetamines (Reference: 11)

Orudis KT – false positives for THC (References: 3, 16, and 18)

Orudis® – (Reference: 3, 18)

OTC diet aids with phenylpropanolamine – (Dexatrim, Accutrim) (References: 11 and 36)

Over-the-counter nasal sprays – (See Vicks inhaler, Afrin) (References: 11, 16, 18, and 20)

Oxaprozin – false positive for THC, Marijuana, Benzodiazepines (References: 3, 18, and 34)

Oxaprozin (Daypro?) – may test false positive for benzodiazepines (References: 57)

Oxazepam – contains benzodiazepines (Reference: 18)

Oxazepam – will test positive for benzodiazepines (not false) (References: 33 and 52)

Ox-pam – may test positive for benzodiazepines (References: 33 and 52)

Oxycodone (Oxycontin) – contains synthetic opiates (Reference: 18 and 33)

Oxymorphone – contains synthetic opiates (Reference: 18)

Oxymorphone (Numorphan) – may test false positive for oxycodone (References: 57)

P

Pamprin® – false positive for THC, Marijuana (References: 3, 18, and 20)

Pantoprazole (Protonix) – false positive for THC (Reference: 37 and 57)

Papaverine (Papaverine) – may test false positive for opiates (References: 57)

Paracetamol (Acetaminophen)/Codeine – (Reference: 33)

Paracetamol with codeine – positive for opiates (References: 33 and 52)

Paracodine® – contains synthetic opiates (Reference: 18)

Paramol – may test positive for opiates (References: 33 and 52)

Paregoric – contains opium/morphine (Reference: 18)

Par-Glycerol-C (CV) – contains codeine (Reference: 18)

Pavacol-D – may test positive for opiates (References: 33 and 52)

Pedacare – false positive for Opioids (Reference: 3)

Pediacof® – contains codeine (Reference: 18)

Pediatric – may test positive for opiates (Reference: 33)

Pediatric BP – Positive for Opiates (Reference: 52)

Pefloxacin – false positive for Opiates (References: 25 and 28)

Pemoline – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Pentobarbital – may test positive for barbiturates (References: 33 and 52)

Pentobarbital Sodium – contains barbiturates (Reference: 18)

Percocet – will test positive (not false) for opiates (References: 3 and 20)

Percodan – contains Oxycodone (Reference: 33)

Percodan® – contains synthetic opiates (References: 3, 18, and 20)

Percovil – will test positive (not false) for opiates (Reference: 20)

Perphenazine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

Perylamine – (Reference: 26)

Phenaphen with Codeine® – (Reference: 18)

Phendimetrazine – false positive for Amphetamines and Ecstasy (References: 3 and 11)

Phenegan-D – false positive for Amphetamines, Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Phenergan VC® – contains codeine (Reference: 18)

Phenergan with Codeine® – (Reference: 18)

Phenergan® – false positive for THC, Methadone (References: 3, 16, 18, and 43)

Phenergan-D – (Reference: 18)

Phenmetrazine – false positive for Amphetamines and Ecstasy (Reference: 3, 11)

Phenobarbital – contains barbiturates (References: 18 and 20)

Phenobarbital – may test positive for barbiturates (References: 33 and 52)

Phenobarbital – may cause false-positive phentolamine test results. (Reference: 56)

Phenobarbitone – may test positive for barbiturates (Reference: 33)

Phenteramine – false positives (Reference: 36)

Phentermine – false positive for Amphetamines and Ecstasy on urine tests (References: 3, 11, and 57)

Phentermine – cross reactant for methamphetamine (Reference: 33)

Phenylephrine – false positive for Amphetamines (References: 3, 18, and 57)

Phenylephrine – false positive for Amphetamines (Reference: 11)

Phenylpropanolamine – false positive for amphetamines (References: 3, 18, 22, 32, and 36)

Phenylpropanolamine (PPA) – false positive for Meth (References: 11 and 16)

Phenypropanolamine – false positive reading for Amphetamines (Reference: 29)

Phenytoin (Dilantin®) – may test false positive for barbiturates (References: 57

Pholcodine – may test positive for opiates (References: 33 and 52)

Pholedrine – false positive for Amphetamines, Meth and Ecstasy (References: 3, 11, 16)

Physetone – may test positive for methadone (Reference: 33, and 52)

Poly-Histine – contains codeine (Reference: 18)

Pondinil® – metabolizes to amphetamine (Reference: 18)

Poppy Seeds contain morphine – positive for Heroin (MDMA), Opiates (References: 3, 16, 17, 20, 21, 25, 26, 29, 32, 48, and 60)

Potentsex pills (Chinese herb) – contain benzodiazepines (Reference: 32)

Prazepam – may test positive for benzodiazepines (References: 33 and 52)

Prenylamine – metabolizes to amphetamine (Reference: 18)

Preparations – positive for opiates (Reference: 33)

Prescription medications that contain codeine – (Reference: 18)

Prescription NSAIDS – (References: 18)
and 20)

Prescription sleeping pills – may test positive for Benzodiazepines (References: 3 and 20)

Prevacid – PPIs may test positive for THC (Reference: 37)

Prilosec – PPIs may test positive for THC (Reference: 37)

Primatene-M – (Reference: 26, 29)

Primatine Tablets – false positive for Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Primidone (Mysoline®) – may test false positive for barbiturates (References: 57)

Procainamide (Procainamide) – may test false positive for amphetamines (References: 57)

Procaine – Positive for Opiates (Reference: 52)

Prochlorperazine – false positive for LSD (Reference: 47)

Promethazine – false positive for THC (References: 3, 16, and 18)

Promethegan – false positive for THC (References: 3, 16, and 18)

Propanolamine – (Reference: 26)

Propoxyphene – contains synthetic opiates (Reference: 18)

Propranolol (Inderal®) – may test false positive for amphetamines (References: 57

Propylephedrine – false positive for Amphetamines and Ecstasy (References: 3, 11, and 18)

Proquin XR (Fluoroquinolone) – false positive for opiates (Reference: 28)

ProSom – may test positive for Benzodiazepines (References: 33 and 52)

Proton pump inhibitors – false positive for THC (Reference: 37 and 55)

Protonix – false positive for THC (Reference: 37 and 55)

Prozac (Fluoxetine Hydrochloride) – false positives for amphetamines (Reference: 31)

Pseudoephederine (Claritin-D®/Sudafed®) – false positives for amphetamines and ecstasy (Reference: 20)

Pseudoephedrine – may be detected as amphetamines (speed) (References: 3, 11, 18, 21, 36, 48, and 57)

Pseudoephedrine – may test positive for amphetamines (Reference: 33)

Pseudoephedrineare – false positive for amphetamines (Reference: 22)

Purim cookies – contain poppy seeds, false positive for opiates (References: 13, 16, and 17)

Pylorid – may test positive for methamphetamines (References: 33 and 52)

Q

Quadrinal® – false positive for Amphetamines, Heroin, Opiates (References: 1 and 18)

Quelichine – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Quelidrine – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Quetiapine (Seroquel) – false positive for amphetamines (Reference: 48)

Quibron Plus – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Quinine in Tonic water – positive for opiates (References: 26, 29 and 32)

Quinacrine (Atabrine/Mepacrine) – may test false positive for amphetamines (References: 57)

Quinolones – (Reference: 25)

R

Rabeprazole – PPIs may test positive for THC (Reference: 37)

Ranitidine – may show false positive for Amphetamines (References: 32, 36, and 52)

Ranitidine – may test positive for methamphetamines (References: 33 and 52)

Rantidine (Zantac®) – may test false positive for amphetamines (References: 57)

Redux – false positive for Amphetamines, Meth and Ecstasy (References: 3, 11, and 16)

Relafen – false positive for Marijuana (Reference: 3)

Remedeine Forte – may test positive for opiates (Reference: 33)

Remedeine – may test positive for opiates (Reference: 33)

Remedine – positive for opiates (References: 33 and 52)

Rescudose – contains morphine (Reference: 18)

Restoril (Temazepam) – is a benzodiazepine (References: 33 and 52)

Rexatal® – contains barbiturates (Reference: 18)

Riboflavin (vitamin B2) – false positive for THC (References: 3, 16, 18, and 21)

Rifampicin (antibiotic) – false positive for Opioids (Reference: 3)

Rifampin – false positive for Opiates (References: 25 and 32 and 57)

Risperidone – false positive for LSD (Reference: 47)

Ritalin® – an Amphetamine-like stimulant (Reference: 18)

Rivotril – may test positive for Benzodiazepines (References: 33 and 52)

Rivotril® – contains benzodiazepines (Reference: 18)

Robitussin – positive for opiates (Reference: 20)

Robitussin A-C® – contains codeine (Reference: 18)

Robitussin Cold and Flu – false positive for Ecstasy (MDMA), Meth (References:
3, 11, 16, and 18)

Robitussin DAC® – contains codeine (Reference: 18)

Robitussin DM – false positive for Heroin, Opiates, Morphine (Reference: 1)

Rohypnol – may test positive for Benzodiazepines (References: 33 and 52)

Romilar – false positive for Heroin, Opiates, Morphine (Reference: 1)

Roxanol – positive for opiates (Reference: 33)

Roxanol – contains morphine (Reference: 18)

Roxicet – contains Oxycodone (Reference: 33)

Rufin – false positive for THC, Marijuana (References: 1 and 3)

S

Secobarbital – contains barbiturates (Reference: 18)

Secobarbital – may test positive for barbiturates (References: 33 and 52)

Secobarbital Sodium Bellergal-S® – contains barbiturates (Reference: 18)

Seconal – may test positive for barbiturates (References: 33 and 52)

Seconal Sodium – contains barbiturates (Reference: 18)

Selegiline (Eldepryl) – false positive for Meth, Amphetamines and Ecstasy (References: 3, 11, 18, 36, and 57)

Sensorcaine – may test false positive for cocaine (Reference: 59)

Serax – may test positive for benzodiazepines (References: 33 and 52)

Serax® – contains benzodiazepines (Reference: 18)

Seroquel (quetiapine) – false-positives for amphetamines (Reference: 48)

Sertraline – false positives for benzodiazepines and LSD (Reference: 44, 47, and 57)

Sertraline – may test positive for benzodiazepines (Reference: 33)

Severedol – positive for opiates (Reference: 33)

Shampoo containing hemp – (Reference: 29)

Silexin – false positive for Heroin, Opiates, Morphine (Reference: 1)

Sinarest – false positive for Amphetamines, Morphine (Reference: 1)

Sine-Aid Tablets Maximum Strength – (Reference: 18)

Sine-Off – false positive for Morphine (Reference: 1)

Sinequan – may test positive for Tricyclic Antidepressants (References: 33 and 52)

Sinex – false positive for Amphetamines (Reference: 3)

Sinubid – false positive for Morphine (Reference: 1)

Sinus Excedrin Extra Strength Caplets – false positive for Amphetamines (References: 3 and 18)

Solfoton® – contains barbiturates (Reference: 18)

Solpadol – positive for opiates (Reference: 33)

Solpadol – may test positive for opiates (References: 33 and 52)

Soma – false positive for Morphine (Reference: 43)

Soma with Codeine – (Reference: 18)

Somnite – may test positive for benzodiazepines (References: 33 and 52)

Soneryl – may test positive for Barbiturates (References: 33 and 52)

Sparfloxacin – (Reference: 25)

St. Joseph’s Cough Syrup – false positive for Heroin, Opiates, Morphine (Reference: 1)

Stesolid – may test positive for Benzodiazepines (References: 33 and 52)

Strong BP – may test positive for opiates (References: 33 and 52)

Suboxone (Buprenorphine) – may test false positive for oxycodone (Reference: 54)

Sudafed – false positive for Amphetamines, Meth and Ecstasy (References: 3, 11, 16, 18, 20, 26, and 29)

Sudafed – may test positive for amphetamines (Reference: 33)

Sustiva (Efanirenz) – false positive for THC or Marijuana (References: 38 and 52)

Sustiva – may test positive for THC (References: 33 and 49)

Synalgos DC® – contains synthetic opiates (Reference: 18)

T

Tavist-D – false positive for Meth and Ecstasy (References: 3, 11, 16, and 18)

Tedral – false positive for Amphetamines, Heroin, Opiates (Reference: 1)

Tegisec® – metabolizes to amphetamine (Reference: 18)

Temazepam (Restoril) – is a benzodiazepine (References: 33 and 52)

Thebacon – may test positive for opiates (References: 33 and 52)

Thioridazine (Mellaril) – false positive for phencyclidine (PCP) and LSD (References: 32, 33 and 47)

Thioridazine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

Thorazine – false positives (Reference: 36)

Tolectin® – false positive for THC, Marijuana (References: 3, 18, and 20)

Tonic water – false positive for cocaine (References: 16 and 18)

Tranxene – may test positive for Benzodiazepines (References: 33 and 52)

Trazodone (trazadone, trazedone) – false positive for amphetamines (Reference: 32 and 57)

Trazodone – false positive for LSD (Reference: 47)

Trendar Cramp Relief Formula – false positive for THC, Marijuana (References: 3, 18, 26, and 29)

Triaminic 12 – false positive for Amphetamines (References: 3 and 18)

Triaminic Expectorant with Codeine® – (Reference: 18)

Triaminicin – false positive for Amphetamines, Morphine (Reference: 1)

Triazolam (Halcion) – Positive for Benzodiazepines (Reference: 52)

TriazolamHalcion® – contains benzodiazepines (Reference: 18)

Tricyclic antidepressants – may produce false-positive results for amphetamines (Reference:
48)

Trimethobenzamide – false positives (Reference: 36)

Trimeprazine – false positive for Tricyclic Antidepressants (TCA) (Reference: 46)

Triminicol – false positive for Morphine (Reference: 1)

Triprolidine – false positive for LSD (References: 3 and 18)

Triptafen – Positive for Tricyclic Antidepressants (Reference: 52)

Triptafen-M – Positive for Tricyclic Antidepressants (Reference: 52)

Trucal – false positive for Heroin, Opiates, Morphine (Reference: 1)

Tryptizol – Positive for Tricyclic Antidepressants (Reference: 52)

Tuinal – Positive for Barbiturates (Reference: 52)

Tussagesic – false positive for Morphine (Reference: 1)

Tussaminic – false positive for Heroin, Opiates, Morphine (Reference: 1)

Tussar 2® – contains codeine (Reference: 18)

Tussar SF® – contains codeine (Reference: 18)

Tussinic – false positive for Heroin, Opiates, Morphine (Reference: 1)

Tussi-Organiden – contains codeine (Reference: 18)

Tylenol (acetaminophen) with Codeine® – (References: 3, 18, 20, and 33)

Tylenol 3 – may cause positive for opiates (Reference: 20)

Tylenol 3 – positive for opiates (References: 33 and 52)

Tylenol 4 – may cause positive for opiates (Reference: 20)

Tylenol Cold (combination) – may test positive for amphetamines (Reference: 33)

Tylenol Simply Sleeps (Diphenhydramine) – false positive PCP results (Reference: 24)

Tylenol Sinus – false positives for Amphetamines and Ecstasy (Reference: 20)

Tylenol Sinus gelcaps, Maximum Strength – false positive for Amphetamines (References: 3 and 18)

Tylenol with codeine – Positive for Opiates (Reference: 52)

Tylex – positive for opiates (References: 33 and 52)

Tylex – may test positive for opiates (Reference: 33)

U

Tramadol (Ultram) – may test false positive for phencyclidine (PCP) and methadone (Reference: 62, 63), and 64)

Unisom Nighttime Sleep Aid – false positive for Morphine (Reference: 43)

V

Valclair – may test positive for Benzodiazepines (References: 33 and 52)

Valerian Root and extract – false positives for Benzodiazepines (Reference: 36)

Valium – may test positive for Benzodiazepines (Reference: 33)

Valium® (Diazepam) – contains benzodiazepines (References: 18 and 20)

Valrelease® – contains benzodiazepines (Reference: 18)

Venlafaxine hydrochloride (Effexor) – false positive for PCP (Reference: 52)

Verapamil – false positive for LSD (Reference: 47)

Vicks Cough Syrup – false positive for Heroin, Opiates, Morphine (Reference: 1)

Vicks Formula 44M – false positive for heroin, Methadone (References: 1, 14, 26, 29, and 43)

Vicks Inhaler – false positive for Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Vick’s Inhaler – may test positive for methamphetamine (References: 33 and 36)

Vicks Nasal Spray – (References: 26 and 29)

Vicks Nyquil – false positive for Ecstasy (MDMA), Meth (References: 3, 11, 16, and 18)

Vicodin ES® – contains synthetic opiates (References: 3 and 18)

Vicodin – may test positive for opiates (References: 33 and 52)

Vitamin B2 – false positive for THC (References: 3, 16, and 18)

Vivacaine – may test false positive for cocaine (Reference: 59)

Voltaren (diclofenac, Cataflam, Arthrotec(combined with misoprostol)) – false positive for THC, Marijuana (References: 3 and 18)

W

Wellbutrin – false positive for Amphetamines (Reference: 12)

Wigraine® – false positive for LSD (References: 3 and 18)

Wygesic – will test positive (not false) for opiates (Reference: 20)

X

Xanax – Positive for Benzodiazepines (Reference: 52)

Xanax® (Niravam, Alprazolam) – contains benzodiazepines (Reference: 18)

Xepin – may test positive for Tricyclic Antidepressants (Reference: 33, 52)

XTC (slang) – may test positive for methamphetamine and ecstasy (Reference: 33, 52)

Z

Zantac (ranitidine) – may test positive for methamphetamines (References: 33 and 52)
Zantac (ranitidine) – may test positive for amphetamines (References: 57)

Zegerid – PPIs may test positive for THC (Reference: 37)

Zoloft – may test false positive for benzodiazepines (Reference: 31)

Zoloft – may test positive for benzodiazepines (Reference: 33)

Zyban – may cause a false positive for amphetamines (Reference: 68)

Zyrtec-D – contains pseudoephedrine that may cause a false positive for amphetamines (References: 3, 11, 18, and 21)

* PDR in this context refers to the Physician’s Desk Reference.

Feedback on False Positives

False positive?

Date: 12/26/2004

My son is addicted cocaine. He came home for a visit, and was sick. I gave him med for sinus treatment which I take as needed. It does not cause drowsiness. I gave him Sudafed and some cough medication, and Amoxicillin. He is currently residing in a Rehab, and had to test when he got back there. His test was positive. My son insisted that he had not taken anything. He says that he drank two cans of beer which were given to him. I have research several sites, and I don’t know what to do. He needs to be in rehab. Some of the info that I have read lists amoxicillin as a cause for false positive. My son also has Hep C. He states that he has been clean since entering rehab.

Cleo

AskDocWeb: Check the label of the cough medication you gave him. Some over the counter cough syrups have codeine in them and that can cause a false positive. Also, the Amoxicillin can cause a false positive for cocaine.

Failing drug tests
Date: 1/26/2005
My husband takes Phenergan and Zantac on a daily basis. He also goes to a Methadone clinic. He passed had every drug test for over a year. Nothing changed he always took these drugs. But he started failing the drug tests. They said it was for Amphitamines. Is this possible? He has passed other drug test given for work. At the same time.

Trina

AskDocWeb: Phenergan is for nausea and vomiting, and only to be used for a short time just for these symptoms. The Zantac is on the list.

Tested positive for marijuana
Date: 7/23/2005
A friend of mine does not use drugs. Yet, his drug test came back positive for marijuana. He had been taking about 3600mg/day of ibuprofen. We would like to find reputable information related to ibuprofen causing false positives for marijuana.

Gary

AskDocWeb: Are you sure he tested positive for marijuana or was it positive for drug abuse? He is taking more than the recommended amount of ibuprofen and overdosing on ibuprofen is known to cause false positives for marijuana on test results.

Tested positive for heroin
Date: 8/6/2005
I feel completely helpless and hopeless. I test positive for heroin and I DO NOT use illegal drugs, but I do take quinine for leg cramps. The testing device is an ion (vacuum-type) device and info would be appreciated. Thank you.

Carolyn

AskDocWeb: If the lab that tested you wasn’t certified, we suggest you get tested by one that is certified. And let them know that you are taking quinine.

Quinine false positive
Date: 12/9/2005
Some websites state that quinine can produce a false positive for cocaine use. Is this true or is it only true for opiates?

BB

AskDocWeb: As far as we know, it is only true for opiates.

Arrested for DUI
Date: 1/5/2006
I was pulled over a year ago and arrested for DUI. After blowing 0.0% because I had not been drinking the police gave me a 5 minute urine drug screen. They claimed it showed THC and meth.?? I use neither. I did tell them prior to the test that I had been taking metabolife and an over the counter allergy med I think Sudafed. All charges were dropped and they sent my urine to the crime lab. Now over a year later they have pressed charges. They said I did not have THC in my urine but I did have methamphetamine antanphetamines. I have never used these illegal substances, could the over the counters produce a false test? Thanks

Julie

AskDocWeb: Yes, Sudafed is known to cause false positives on some urine drug tests.

Tested positive for amphetamines
Date: 2/2/2006
I recently tested positive for amphetamines, I do NOT use drugs and this was for a really good job. I took Nyquil the night prior to the test because I’ve had a cold for the past 2 weeks. I know it had to be the nyquil, is there any way to convince the employer. Prior to the screening I did disclose the fact that I used Nyquil.

Dan

AskDocWeb: The only way we know to convice an employer when a urine drug test produces a false positive is to get a GC/MS confirmation test on the original sample.

False positives?
Date: 2/7/2006
Will any of the following give a false positive cocaine reading. Zithromax, Prednisone, Albuterol liquid, or Levaquin

Ross

AskDocWeb: Since Prednisone is a steroid, it may show up on a drug screen if they are testing for steroids, otherwise no.

Hydrocodone false positive
Date: 3/8/2006
I recently took a drug test and tested positive for hydrocodone (per saliva test). I have Never taken hydrocodone or any prescription pain medication. The day of the test, I took 2 Excedrin Migraines and 2 ibuprofen. Could these two medications produce a false hydrocodone result?

Miriam

AskDocWeb: We know that Excedrin may cause false positives but we don’t know if it was for hydrocodone or something else. Ibuprofen may cause false positives for THC but not hydrocodone.

Positive for methadone
Date: 3/16/2006
Our company does random drug testing and called me the other day for a urine test. My results for methadone came up positive but I have never touched a drug in my life. I have not taken any medication and I have no idea what could have caused this. Is there any thing you can tell me that may cause a false positive.

ML

AskDocWeb: Yes, Nyquil Nighttime Cold Medicine has been reported to sometimes cause false positives for Methadone for up to 2 days after taking it.

Drug tests
Date: 3/23/2006
I am looking into a career with the CIA and was wondering if you had any idea how extensive their drug tests are. I have been taking Vicodin for my migraines, cold medication(Nyquil at night and Tylenol during the day) is this going to be a problem? Any info would be appreciated.

Ed

AskDocWeb: We are pretty sure that the CIA knows which products cause false positives. Many people take Tylenol and Nyquil for their colds and they will know that, but to be on vicodin for a migraine is something else. That could be a problem.

In trouble
Date: 3/23/2006
My boyfriend got arrested for possession of marijuana and he quit smoking because he knows its not even worth getting in trouble over, but his drug test came back positive for opiates and he doesn’t do any drugs. He takes Advil sometimes for headaches and he just had a cold and took some cold medicine but other then that he doesn’t do anything. Is there any way at all to prove his innocence? He’s being told now there is a warrant out for his arrest and he will probably be arrested tomorrow…but for nothing and I don’t understand this. He’s got a warrant out for his arrest for doing what he is supposed to do and still he is in trouble…

Caiti

AskDocWeb: For others in this situation, if you take cold medicine it may be helpful to keep the receipt as proof of purchase.

False positive?
Date: 3/24/2006
Can Fioricet cause a false positive for amphetamines?

sandra

AskDocWeb: No, Fioricet is a combination drug that contains acetaminophen (Tylenol), caffeine, and butalbital. Butalbital is a barbiturate, which is a depressant. Amphetamines are stimulants and have very different chemical structures. Read more feedback about false positives.