

Home Site Map Resources Contact Us Privacy Policy Current Research Project

Hair Loss Products

For Women

For Men

Moved here

Weight Loss

Pain Relief

Skin Care

Herpes

Stop Smoking

General Health

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 useage, they are probably not required to use a certified drug testing lab, which means you have a greater chance of getting a false positive.

Listed below are products reported to cause a false positive drug test result. With your help, this will grow into a comprehensive list.

Last updated, December 19, 2008.

Substances that cause false positives

4-Way Nasal Spray - false positive for Amphetamines, Morphine (Ref: 1, 2, 7)
Accutrim - false positive for Ecstasy (MDMA), Meth (Ref: 11, 16, 18)
Acetaminoph w/codeine - false positive for Morphine (Ref: 1)
Acet-AM - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Acro-Lase Plus® contains barbiturates (Ref: 18)
A.P.C. w/codeine - false positive for Morphine (Ref: 1)
A.R.M. - false positive for Amphetamines (Ref: 3, 18)
Actifed - false positive for Amphetamines (Ref: 2, 3, 7, 18)
Actifed with Codeine Cough Syrup® (Ref: 18)
Adderall® - is an amphetamine, positive for Meth (Ref: 2008 PDR, 18, 19)
Advil - false positive for THC, Marijuana (Ref: 1, 14, 16, 18, 20, 26, 29) (Ref. 22 says NO)
Afrin - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Aleve - false positive for THC, Marijuana (Ref: 3, 16, 18)
Alka-Seltzer - false positive for Amphetamines (Ref: 2, 7)
Alka-Seltzer Plus - false positive for Amphetamines, Morphine (Ref: 1, 2, 7)
Allerest - false positive for Amphetamines, Ecstasy, Meth and Morphine (Ref: 1, 2, 3, 7, 11, 16, 18)
Alprazolam contains benzodiazepines (Ref: 18)
Amantadine (Ref: 32)
Ambenyl contains codeine (Ref: 18)
Amesec - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Amfepramone - false positive for Amphetamines, Ecstasy (MDMA), Meth (Ref: 3, 11, 16)
Amifepramone - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Amineptine - false positive for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Amitriptyline - false positive for LSD (Ref: 3)
Amogel PG® contains opium/morphine (Ref: 18)
Amoxicillin - false positive for cocaine (Ref: 13, 16, 18, 20, 21, 26, 29)
Ampicillin - false positive for cocaine (Ref: 29)
Amphetaminil metabolizes to amphetamine (Ref: 18)
Ampicin - can cause false positive for opiates (Ref: 20)
Anaprox - false positive for THC, Marijuana (Ref: 1, 3, 18)
Ansaid - false positive for marijuana (Ref: 3)
Anti Anxiety medication, most - false positive for benzodiazepines (Ref: 3)
Anti Inflammatories such as Naproxyn (Ref: 26)
Antiasthmatics that contain phenobarbitol - false positive for barbiturates (Ref: 3)
Antibiotics - false positives for Heroin, Cocaine (Ref: 13, 18, 20)
Antrocol Elixor® contains barbiturates (Ref: 18)
Apo-Naproxen - false positive for THC, Marijuana (Ref: 1)
Artane - false positive for LSD (Ref: 3)
Ascriptin w/codeine - false positive for Morphine (Ref: 1)
Aspirin with Codeine (Ref: 18)
Asthma medications - false positives for Amphetamines and Ecstasy (Ref: 20, 21)
Astramoprh PF ® contains morphine (Ref: 18)
Ativan® contains benzodiazepines (Ref: 18)
Atripla - false positive for cannabinoid THC (Ref: 39)
B2 vitamin - false positive for THC (Ref: 21)
Bayer Select Maximum Strenght Sinus Pain Relief Caplets - false positive for Amphetamines (Ref: 3, 18)
Bayer Select Pain Relief Formula - false positive for THC, Marijuana (Ref: 3, 18)
Bentyl® - false positive for LSD (Ref: 3, 18)
Benylin - false positive for Opioids (Ref: 3)
Benzatropine/Artane® (Ref: 18)
Benzedrine® - Amphetamines (Ref: 18)
Benzphetamine - false positives for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Biphetamine® for Amphetamines (Ref: 18)
Black Pearls (Tung Sheuh pills) contain benzodiazepines (Ref: 32)
Broncholate CS contains codeine (Ref: 18)
Bromocriptine/Parlodel® (Ref: 18)
Bromocription - false positive for LSD (Ref: 3)
Bromphenlramlne - false-Positive for Amphetamine (Ref: 22)
Bronkaid - false positive for Amphetamines, Heroin, Opiates, Ecstasy, Meth (Ref: 1, 3, 16, 18)
Bronkotabs - false positive for Amphetamines, Heroin, Opiates (Ref: 1, 11)
Buprenex® contains synthetic opiates (Ref: 18)
Buprenorphine contains synthetic opiates (Ref: 18)
Bupropion (Wellbutrin) - false positive for Amphetamines (Ref: 12, 31, 32)
Cafergot® - false positive for LSD (Ref: 3, 18)
Caldecon - false positive for Amphetamines, Morphine (Ref: 1, 2, 7,)
Capital and Codeine Oral Solution - false positive for Opioids (Ref: 3, 18)
Captagon® metabolizes to amphetamine (Ref: 18)
Cathne - false positives for Amphetamines, Meth and Ecstasy (MDMA) (Ref: 3, 11, 16)
Cheracol contains codeine (Ref: 18)
Cheracol Sinus - false positive for Amphetamines (Ref: 3)
Chinese herb pills contain benzodiazepines (Ref: 32)
Chlordiazepoxide contains benzodiazepines (Ref: 18)
Chiorpromazlne - False-Positive for Amphetamine (Ref: 22, 26)
Chlorpromazine - false positive for Opiates (Also false for pregnancy) (Ref: 23, 32)
Chlorpromazine - false positive for phencyclidine (Ref: 32)
Cipro (antibiotic) - false positives for opiates (Ref: 25, 32)
Clinafloxacin - (Ref: 25)
Clinoril - false positive for THC, Marijuana (Ref: 3, 18)
Clobenzorex - false positives for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Clonazepam contains benzodiazepines (Ref: 18)
Codeine - false positives for Amphetamines (Ref: 14)
Codeine - will test positive (not false) for opiates (Ref: 20)
Codinal PH® contains codeine (Ref: 18)
Coffee-Break - false positive for Morphine (Ref: 1)
Cold remedies with dextromethorphan - positive for opiates (heroin) (Ref: 21)
Combivent inhaler - false positive for meth in urine tests (Ref: 19)
Comtrex - false positive for Opioids (Ref: 3)
Concerta - false positive for meth in urine tests (Ref: 19)
Contac - false positive for Amphetamines, Morphine (Ref: 1, 7, 20)
Contact - false positives for Amphetamines, Meth and Ecstasy (Ref: 2, 3, 7, 11, 16, 18)
Contact Non-Drowsy Formula Sinus Caplets - false positive for Amphetamines (Ref: 3, 18)
Control - false positive for Morphine (Ref: 1)
Cough medicines - See if any ingredients are on this list (Ref: 6, 20)
Cough suppressants with Dextromethorphan (DXM) - false positive for Heroin (MDMA) (Ref: 16)
Cows head pills (Chinese herb) contain benzodiazepines (Ref: 32)
Cramp End Tablets - false positive for THC, Marijuana (Ref: 3, 18)
Cylert - false positives for Amphetamines and Ecstasy (Ref: 3, 11)
Dalmane® contains benzodiazepines (Ref: 18)
Datril - false positives for Marijuana (Ref: 1)
Darvon® contains synthetic opiates (Ref: 18)
Daypro - false positives for benzodiazepines (Ref: 34)
Deconsal contains codeine (Ref: 18)
Demerol - tests positive for opiates (Ref: 26, 29)
Deprenyl - false positives for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Desipramine (Ref: 32)
Desoxyephedrine - false positive for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Desoyn® contains d-methamphetamine (Ref: 18)
Diet aids with phenylpropanolamine (Dexatrim, Accutrim) - false positive for Amphetamines (Ref: 11, 16, 18)
Dexatrim - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Dexdenfluramine - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Dexedrine is an Amphetamine (Ref: 3, 11, 18)
Dexfenfluramine - false positive for Amphetamines (Ref: 3, 11)
Dextroamphetamine - false positive for Amphetamines (Ref: 3)
Dextromethorphan hydrobromide or DXM - false positives for amphetamines (Ref: 6, 11)
Dextromethorphan - false positive for Heroin, Opiates, Morphine (Ref: 1, 3, 16, 21, 26, 29, 32)
DHEA - false positive for anabolic steroid use (Ref: 13)
Diabetes - false positives for Amphetamines, Cocaine, THC, Ecstasy, Meth and Opiates (Ref: 3, 15, 16, 20, 21)
Diabismul® contains opium/morphine (Ref: 18)
Diazepam - false positive for PCP (Ref: 29)
Diazepam (generic name for Valium) - contains benzodiazepines (Ref: 18, 20, 26)
Dicyclomine (Ref: 18)
Didrex - false positive for Amphetamines (Ref: 3, 11)
Diet aids with phenylpropanolamine (Dexatrim, Accutrim) - false positive for amphetamines (Ref: 2, 10, 16)
Dietac - false positive for Morphine (Ref: 1, 2, 7)
Dihyrocodeine contains synthetic opiates (Ref: 18)
Dilantin - false positives for Barbiturates (Ref: 3, 20)
Dilaudid® contains synthetic opiates (Ref: 18)
Dimetane-DC Cough Syrup ® contains codeine (Ref: 18)
Dimetapp - false positive for Morphine, Meth, Ecstasy (Ref: 1, 2, 7, 11, 16, 18)
Dimethylamphetamine metabolizes to methamphetamine and amphetamine (Ref: 18)
Dietac - false positive for Amphetamines (Ref: 7)
Dimetapp - false positive for Amphetamines (Ref: 3, 7)
Dinintel® metabolizes to amphetamine (Ref: 18)
Diphenhydramine - false positive PCP results (Ref: 24)
Diphenhydramine - false positive for phencyclidine (Ref: 32)
Doco children's cough syrup - false positive for Opioids (Ref: 3)
Dolobid - false positive for THC, Marijuana (Ref: 3, 18)
Dolophine® contains synthetic opiates (Ref: 18)
Donnagel-PG ® contains opium/morphine (Ref: 18)
Donnatal® contains barbiturates (Ref: 18)
Donnatol (for irritable bowel syndrome) - false positive for barbiturates (Ref: 3)
Dormonocet® contains benzodiazepines (Ref: 18)
Doxylamine - false positive for phencyclidine (Ref: 32)
Dristan Cold caplets - false positive for Amphetamines (Ref: 3)
Dristan Cough Formula - false positive for Heroin, Opiates, Morphine (Ref: 1, 18)
Dristan Nasal Spray - false positive for Amphetamines (Ref: 26, 29)
Drixoral Cold and Flu - false positive for Amphetamines (Ref: 3, 18)
Dronabad® (Ref: 18)
Dronabinol (Marinol) - false positives for THC (Ref: 16, 18)
Duramorph® contains morphine (Ref: 18)
Durophet® Amphetamines (Ref: 18)
Edecrin - false positive for THC, Marijuana (Ref: 3, 18)
Efavirenz - false positive for THC, Marijuana (Ref: 32)
Effexor Tablets (venlafaxine hydrochloride) - false positive for PCP (Ref: 27, 33)
Efidac/24 - false positive for Amphetamines (Ref: 3, 18)
Efotamine - false positive for LSD (Ref: 3)
Elavil - false positives for opiates for up to three days, LSD (Ref: 3, 26, 29)
Eldepryl - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Elderpryl® metabolizes to methamphetamine and amphetamine (Ref: 18)
Emprin with Codeine® (Ref: 18)
Ephedrol, Ephedra (Ma Haung) - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Ephedrine - false positive for Amphetamines, Meth, and Ecstasy (Ref: 2, 3, 11, 16, 18, 29, 30, 32)
Empirin w/codeine - false positive for Morphine, Opioids (Ref: 1, 3, 20)
Enoxacin - false-positive for opiates (Ref: 25, 28)
Ergostat® - false positive for LSD (Ref: 3, 18)
Ergotamine (Ref: 18)
Estasule Minus - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Etafediabe - false positive for Amphetamines, Meth and Ecstasy (Ref: 3, 11, 16)
Ethylamphetamine metabolizes to amphetamine (Ref: 18)
Excedrin IB - false positives for Marijuana (Cannabis) THC (Ref: 3, 16, 18)
Ephedra - false positives for Amphetamines and Ecstasy (Ref: 20, 22)
Ephedrine-based compounds - false positives for Amphetamines and Ecstasy (Ref: 20, 22)
Famprofazone - false positive for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Feldene - false positives for THC (Ref: 3, 18)
Fencamine metabolizes to methamphetamine and amphetamine (Ref: 18)
Fenelylline - false positive for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Fenfluramine - false positive for Ecstasy (Ref: 3, 11)
Fenoprofin - false positive for Marijuana, Amphetamines, Barbiturates (Ref: 1, 7)
Fenproporex metabolizes to amphetamine (Ref: 18)
Fenproyorex - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Finedal® metabolizes to amphetamine (Ref: 18)
Fioricet with Codeine® (Ref: 18, 20)
Fiorinal w/codeine - false positive for Morphine (Ref: 1, 3, 18, 20)
Fluoroquinolone antibiotics - false positive for opiates (Ref: 28, 32)
Fluoxetine (Prozac) - false positives for amphetamines (Ref: 31)
Flurazepam contains benzodiazepines (Ref: 18)
Flurbiprofen - false positive for marijuana (Ref: 3)
Fluriprofen® (Ref: 18)
Fluspirilene may test positive for amphetamines (Ref: 26)
Furfenorex metabolizes to methamphetamine and amphetamine (Ref: 18)
Gatifloxacin (Ref: 25)
Genpril - false positive for THC, Marijuana (Ref: 3, 18)
Gradumet® contains d-methamphetamine (Ref: 18)
Halotest-25 (Ref: 40)
Haltran - false positive for THC, Marijuana (Ref: 3, 18)
Hamantashen may test positive for opiates. (Ref: 13)
Hempseed Oil - false positive for THC (Ref: 3, 16, 21, 29)
Hold Cough Suppressant - false positive for Heroin, Opiates, Morphine (Ref: 1)
Homatropine Methylbromide contains synthetic opiates (Ref: 18)
Hycodan® contains synthetic opiates (Ref: 18)
Hydergine - false positive for LSD (Ref: 3)
Hydrocodone Bitartrate contains synthetic opiates (Ref: 18)
Hydrocodone contains synthetic opiates (Ref: 18)
Hydrocodone - false positive for oxycodone (Ref: 41)
Hydromorphone contains synthetic opiates (Ref: 18)
Hydroymethamphetamone - false positive for Amphetamines (Ref: 3)
Ibuprin - false positive for marijuana (Ref: 3)
Ibuprofen - false positive for Marijuana (THC) (Ref: 1, 3, 16, 18, 29)
Ifenoprofen - false positive for THC, Marijuana (Ref: 3, 13, 18, 21, 26)
Imitrex Hydergine® (Ref: 3, 18)
Indocin - false positive for THC, Marijuana (Ref: 3, 18)
Infantol Pink ® contains opium/morphine (Ref: 18)
Infumorf contains morphine (Ref: 18)
Isoclor Expectorant contains codeine (Ref: 18)
Kaoden with Codeine® (Ref: 18)
Kaodene with Paregoric® contains opium/morphine (Ref: 18)
Kenesed® contains barbiturates (Ref: 18)
Ketamine - false positive for PCP (Ref: 16, 32)
Ketoprofen - false positive for THC (Ref: 3, 16, 18)
Kidney disease - false positive for Cocaine (Ref: 3, 16, 20)
Kidney infection - false positive for Amphetamines, THC, Ecstasy, and Opiates (Ref: 3, 15, 16, 21)
Klonopin® contains benzodiazepines (Ref: 18)
Levaquin® - false positive for opiates (Ref: 35)
Levofloxacin (antibiotic) - false positives for opiates (Ref: 25, 28)
Libritab® contains benzodiazepines (Ref: 18)
Librium® contains benzodiazepines (Ref: 18)
Limbitrol® contains benzodiazepines (Ref: 18)
Lisuride - false positive for LSD (Ref: 3)
Lisuride/Dopergin® (Ref: 18)
Liver Disease - false positive for Opiates, Ecstasy, THC and Amphetamines (Ref: 3, 15, 16, 20, 21)
Lodine - false positive for THC, Marijuana (Ref: 3, 18, 20)
Lomefloxacin (Ref: 25)
Loprazolam contains benzodiazepines (Ref: 18)
Lorazepam contains benzodiazepines (Ref: 18)
Lortab - an opioid analgesic (PDR*)
Luminal® contains barbiturates (Ref: 18)
Lysergol - false positive for LSD (Ref: 3, 18)
Ma Huang (Ephedra sinica) - false positives for Amphetamines and Ecstasy (Ref: 20, 32)
Marax - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Margestic - false positive for Opioids (Ref: 3)
Marinol® false positive for Marijuana (THC) (Ref: 3, 18)
Maximum Strength Sinus Gelcaps (Ref: 18)
Maximum Strength Sine-aid - false positive for Amphetamines (Ref: 3)
Maximum Strength Sudafed Sinus - false positive for Amphetamines (Ref: 3)
Maximum Strength Tylenol Sinus gelcaps - false positive for Amphetamines (Ref: 3, 18)
Meclomen - false positive for THC, Marijuana (Ref: 3, 18)
Mediprim - false positive for marijuana (Ref: 3)
Medipren - false positive for THC, Marijuana (Ref: 3, 18)
Mefenorex - false positive for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Menstrual cramp medications like Midol and Trendar (Ref: 26)
Meperidine - false positive for phencyclidine (Ref: 32)
Mephentermine - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Mesocarb - false positive for Meth and Ecstasy (Ref: 3, 11, 16, 18)
Methadone contains synthetic opiates (Ref: 18)
Methoxyphenamine - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Methphenidate - false positive for Amphetamines and Ecstasy (Ref: 11)
Methylphenidate (Ritalin) an Amphetamine-like stimulant (Ref: 3, 32)
Methysergide/Sansert® (Ref: 18)
Methysergiside - false positive for LSD (Ref: 3)
Midol - false positive for THC, Marijuana (Ref: 3, 18, 26, 29)
Mini-thins - false positives for Amphetamines and Ecstasy (Ref: 20)
Miracle herb pills (Chinese herb) contain benzodiazepines (Ref: 32)
Morazone - false positive for Meth and Ecstasy (Ref: 3, 11, 16)
Morax - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Motrin - false positive for THC, Marijuana (Ref: 1, 3, 16, 18, 20, 26, 29)
Moxifloxacin (Ref: 25)
MS Contin Tablets® contains morphine (Ref: 18)
MSIR® contains morphine (Ref: 18)
Mudrane GC® contains barbiturates (Ref: 18)
Naldecon - false positive for Morphine (Ref: 1)
Nalfon - false positive for Marijuana, Amphetamines, Barbituates, Benzodiazephines, Methaqualone (Ref: 1, 3, 7, 18)
Naprosyn - false positive for THC, Marijuana (Ref: 1, 3, 18)
Naproxen (Aleve) - false positive for THC, Marijuana (Ref: 1, 3, 16, 21)
Naproxyn (Ref: 26)
Nasal sprays (Vicks inhaler, Afrin) - false positive for Amphetamines and Ecstasy (Ref: 2, 10, 16, 21)
Navonaprox - false positive for THC, Marijuana (Ref: 1)
Nembutal Sodium contains barbiturates (Ref: 18)
Neosynephren - false positive reading for Amphetamines (Ref: 26, 29)
Neosynephrine - False positive for Amphetamines (Ref: 3, 18, 26)
No Drowsiness Sinarest Tablets (Ref: 3, 18)
Nonprescription products that contain opium (i.e., morphine) (Ref: 18)
Norfloxacin (Ref: 25)
Novahistine DH® contains codeine (Ref: 18)
Novahistine Expectorant® contains codeine (Ref: 18)
NSAIDS - false positive for THC, Marijuana (Ref: 3, 18, 20, 32) (Ref. 22 says NO)
Nucofed Expectorant contains codeine (Ref: 18)
Numorphan® contains synthetic opiates (Ref: 18)
Nuprin - false positive for THC (Ref: 3, 16, 18, 20, 26, 29)
Nyquil - false positive for Amphetamines, Heroin, Opiates, Morphine, Meth, Ecstasy (Ref: 1, 3, 11, 14, 16, 18, 19, 20, 26, 29)
Obetrol® Amphetamines (Ref: 18)
Ofloxacin (antibiotic) - false positives for opiates (Ref: 25, 28)
Oramorph contains morphine (Ref: 18)
Ornade - false positive for Amphetamines (Ref: 3, 18)
Ortain - false positive for Amphetamines (Ref: 2, 7, 11)
Orudis KT - false positives for THC (Ref: 3, 16, 18)
Orudis® (Ref: 3, 18)
OTC diet aids with phenylpropanolamine (Dexatrim, Accutrim) (Ref: 11)
Over-the-counter nasal sprays (See Vicks inhaler, Afrin) (Ref: 11, 16, 18, 20)
Oxaprozin - false positive for THC, Marijuana, Benzodiazepines (Ref: 3, 18, 34)
Oxazepam contains benzodiazepines (Ref: 18)
Oxycodone contains synthetic opiates (Ref: 18)
Oxymorphone contains synthetic opiates (Ref: 18)
Pamprin® - false positive for THC, Marijuana (Ref: 3, 18, 20)
Pantoprazole - false positive for THC (Ref: 37)
Paracodine® contains synthetic opiates (Ref: 18)
Paregoric contains opium/morphine (Ref: 18)
Par-Glycerol-C (CV) contains codeine (Ref: 18)
Pedacare - false positive for Opioids (Ref: 3)
Pediacof® contains codeine (Ref: 18)
Pefloxacin - false positive for Opiates (Ref: 25, 28)
Pemoline - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Pentobarbital Sodium contains barbiturates (Ref: 18)
Percocet - will test positive (not false) for opiates (Ref: 3, 20)
Percodan® contains synthetic opiates (Ref: 3, 18, 20)
Percovil - will test positive (not false) for opiates (Ref: 20)
Perylamine (Ref: 26)
Phenaphen with Codeine® (Ref: 18)
Phendimetrazine - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Phenergan-D (Ref: 18)
Phenegan-D - false positive for Amphetamines, Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Phenergan VC® contains codeine (Ref: 18)
Phenergan with Codeine® (Ref: 18)
Phenergan® - false positive for THC (Ref: 3, 16, 18)
Phenobarbital contains barbiturates (Ref: 18, 20)
Phenmetrazine - false positive for Amphetamines and Ecstasy (Ref: 3, 11)
Phentermine - false positive for Amphetamines and Ecstasy on urine tests (Ref: 3, 4, 11)
Phenylephrine - false positive for Amphetamines (Ref: 3, 18)
Phenylpropanolamine - false positive for amphetamines (Ref: 3, 18, 22, 30, 32)
Phenylephrine - false positive for Amphetamines (Ref: 11)
Phenylpropanolamine (PPA) - false positive for Meth (Ref: 11, 16)
Phenypropanolamine - false positive reading for Amphetamines (Ref: 29)
Phenypropan-Olamine - false positive for Amphetamines (Ref: 2, 7) (This is an active ingredient in Actifed, Alka-Seltzer, Alka-Selzer Plus, Allerest, Caldecon, Contac, Dietac, Dimetapp, 4-Way Nasal Spray, Ortain, Sinarest, Triaminicin)
Pholedrine - false positive for Amphetamines, Meth and Ecstasy (Ref: 3, 11, 16)
Poly-Histine contains codeine (Ref: 18)
Pondinil® metabolizes to amphetamine (Ref: 18)
Poppy Seeds contain morphine - positive for Heroin (MDMA), Opiates (Ref: 3, 16, 17, 20, 21, 25, 26, 29, 32)
Potentsex pills (Chinese herb) contain benzodiazepines (Ref: 32)
Prenylamine metabolizes to amphetamine (Ref: 18)
Prescription medications that contain codeine (Ref: 18)
Prescription NSAIDS (Ref: 18, 20)
Prescription sleeping pills will test positive for Benzodiazepines (Ref: 3, 20)
Primatene-M (Ref: 26, 29)
Primatine Tablets - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Promethazine - false positive for THC (Ref: 3, 16, 18)
Promethegan - false positive for THC (Ref: 3, 16, 18)
Propanolamine (Ref: 26)
Propoxyphene contains synthetic opiates (Ref: 18)
Propylephedrine - false positive for Amphetamines and Ecstasy (Ref: 3, 11, 18)
Proton pump inhibitors - false positive for THC (Ref: 37)
Protonix - false positive for THC (Ref: 37)
Prozac (Fluoxetine Hydrochloride) - false positives for amphetamines (Ref: 31)
Pseudoephederine - false positives for Amphetamines and Ecstasy (Ref: 20)
Pseudoephedrine may be detected as amphetamines (speed) (Ref: 3, 11, 18, 21, 30)
Pseudoephedrineare - false positive for amphetamines (Ref: 22)
Purim cookies contain poppy seeds, false positive for opiates (Ref: 13, 16, 17)
Quadrinal® - false positive for Amphetamines, Heroin, Opiates (Ref: 1, 18)
Quelidrine - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Quelichine - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Quibron Plus - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Quinine in Tonic water - positive for opiates (Ref: 26, 29, 32)
Quinolones (Ref: 25)
Ranitidine - false positive for Amphetamines (Ref: 32)
Redux - false positive for Amphetamines, Meth and Ecstasy (Ref: 3, 11, 16)
Relafen - false positive for Marijuana (Ref: 3)
Rescudose contains morphine (Ref: 18)
Rexatal® contains barbiturates (Ref: 18)
Riboflavin (vitamin B2) - false positive for THC (Ref: 3, 16, 18, 21)
Rifampin - false positive for Opiates (Ref: 25, 32)
Rifampicin (antibiotic) - false positive for Opioids (Ref: 3)
Ritalin® an Amphetamine-like stimulant (Ref: 18)
Rivotril® contains benzodiazepines (Ref: 18)
Robitussin - positive for opiates (Ref: 20)
Robitussin A-C® contains codeine (Ref: 18)
Robitussin Cold and Flu - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Robitussin DAC® contains codeine (Ref: 18)
Robitussin DM - false positive for Heroin, Opiates, Morphine (Ref: 1)
Romilar - false positive for Heroin, Opiates, Morphine (Ref: 1)
Roxanol contains morphine (Ref: 18)
Rufin - false positive for THC, Marijuana (Ref: 1, 3)
Secobarbital contains barbiturates (Ref: 18)
Secobarbital Sodium Bellergal-S® contains barbiturates (Ref: 18)
Seconal Sodium contains barbiturates (Ref: 18)
Selegiline (Eldepryl) - false positive for Meth, Amphetamines and Ecstasy (Ref: 3, 11, 18)
Serax® contains benzodiazepines (Ref: 18)
Shampoo containing hemp (Ref: 29)
Silexin - false positive for Heroin, Opiates, Morphine (Ref: 1)
Sinarest - false positive for Amphetamines, Morphine (Ref: 1, 2, 7)
Sine-Aid Tablets Maximum Strength (Ref: 18)
Sine-Off - false positive for Morphine (Ref: 1)
Sinex - false positive for Amphetamines (Ref: 3)
Sinubid - false positive for Morphine (Ref: 1)
Sinus Excedrin Extra Strength Caplets - false positive for Amphetamines (Ref: 3, 18)
Solfoton® contains barbiturates (Ref: 18)
Soma with Codeine (Ref: 18)
Sparfloxacin (Ref: 25)
St. Joseph's Cough Syrup - false positive for Heroin, Opiates, Morphine (Ref: 1)
Sudafed - false positive for Amphetamines, Meth and Ecstasy (Ref: 3, 11, 16, 18, 20, 26, 29)
Sustiva (Efanirenz) - false positive for THC or Marijuana (Ref: 38)
Synalgos DC® contains synthetic opiates (Ref: 18)
Tanning lotion containing hemp (Ref: 2)
Tavist-D - false positive for Meth and Ecstasy (Ref: 3, 11, 16, 18)
Tedral - false positive for Amphetamines, Heroin, Opiates (Ref: 1)
Tegisec® metabolizes to amphetamine (Ref: 18)
Thioridazine - false positive for phencyclidine (Ref: 32)
Tolectin® - false positive for THC, Marijuana (Ref: 3, 18, 20)
Tonic water - false positive for cocaine (Ref: 16, 18)
Trazedone (Ref: 32)
Trendar Cramp Relief Formula - false positive for THC, Marijuana (Ref: 3, 18, 26, 29)
Triaminic 12 - false positive for Amphetamines (Ref: 3, 18)
Triaminic Expectorant with Codeine® (Ref: 18)
TriazolamHalcion® contains benzodiazepines (Ref: 18)
Triaminicin - false positive for Amphetamines, Morphine (Ref: 1, 2, 7)
Triminicol - false positive for Morphine (Ref: 1)
Triprolidine - false positive for LSD (Ref: 3, 18)
Trucal - false positive for Heroin, Opiates, Morphine (Ref: 1)
Tussagesic - false positive for Morphine (Ref: 1)
Tussaminic - false positive for Heroin, Opiates, Morphine (Ref: 1)
Tussar 2® contains codeine (Ref: 18)
Tussar SF® contains codeine (Ref: 18)
Tussi-Organiden contains codeine (Ref: 18)
Tussinic - false positive for Heroin, Opiates, Morphine (Ref: 1)
Tylenol (acetaminophen) with Codeine® (Ref: 3, 18, 20)
Tylenol 3 - can cause positive for opiates (Ref: 20)
Tylenol 4 - can cause positive for opiates (Ref: 20)
Tylenol Sinus gelcaps, Maximum Strength - false positive for Amphetamines (Ref: 3, 18)
Tylenol Sinus - false positives for Amphetamines and Ecstasy (Ref: 20)
Valerian Root and extract - false positives for Benzodiazepines (Ref: 36)
Valium® contains benzodiazepines (Ref: 18, 20)
Valrelease® contains benzodiazepines (Ref: 18)
Venlafaxine hydrochloride (Effexor) - false positive for PCP (Ref: 27, 33)
Vicks Formula 44M - false positive for heroin (Ref: 1, 14, 26, 29)
Vicks Cough Syrup - false positive for Heroin, Opiates, Morphine (Ref: 1)
Vicks Inhaler - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Vicks Nasal Spray (Ref: 26, 29)
Vicks Nyquil - false positive for Ecstasy (MDMA), Meth (Ref: 3, 11, 16, 18)
Vicodin ES® contains synthetic opiates (Ref: 3, 18)
Vitamin B2 - false positive for THC (Ref: 3, 16, 18)
Voltaren - false positive for THC, Marijuana (Ref: 3, 18)
Wellbutrin - false positive for Amphetamines (Ref: 12)
Wigraine® - false positive for LSD (Ref: 3, 18)
Wygesic - will test positive (not false) for opiates (Ref: 20)
Xanax® contains benzodiazepines (Ref: 18)
Zantac - false positive for Amphetamines (Ref: 30)
Zoloft - false positive for benzodiazepines (Ref: 31)

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

Feedback on False Positives

Subj: 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 will cause a false positive. Also, the Amoxicillin can cause a false positive for cocaine.

Subj: 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.

Subj: 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.

Subj: 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.

Subj: 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.

Subj: 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.

Subj: 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: That is beyond the scope of what we deal with here. This website is about the side effects of health products.

Subj: 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.

Subj: 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 both Excedrin and Ibuprofen can cause false positives but we don't know if it was for hydrocodone or something else.

Subj: 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 cause false positives for Methadone for up to 2 days after taking it.

Subj: 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 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.

Subj: 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.

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

AskDocWeb: Yes it can, it is a barbiturate.

Read more feedback about false positives.

Last post: 10/11/2009

AskDocWeb, Inc. believes this information should be available to everyone that has a false positive on a urine drug test. For some people their job is at stake, for others it may make the difference in deciding the custody of their children.

If you believe this information should be available to the public then make a donation to help support this website.

Home Site Map Resources Contact Us Privacy Policy Current Research Project
This website is protected by copyright © 2004-2008 Askdocweb, Inc. All Rights Reserved. This is a layman's report and is not intended to replace discussions with a health care provider. Do not use the information on this forum as a substitute for your doctor's advice. Always consult your doctor before taking any drug and follow your doctor's directions. Source material: United States Food and Drug Administration, Medline, Physician's Desk Reference, Universities and people just like you who are concerned about the side effect of health products.