Report on Kava Side Effects and Usage

Kava Kava

Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using kava, also known as kava kava (Piper methysticum). These are referred to as drug/herb interactions.

Note: Kava kava is sometimes called cava cava.

Warning 1 – Contraindications: Endogenous depression, pregnancy and lactation. There is a concern that kava may affect the uterus and some of the chemicals in kave pass into breast milk.

Warning 2 – Liver problems: Taking kava with some medications that are changed or metabolized by the liver may increase the effects, side effects, and the length of time these medications remain in your system. Some of the drugs that are changed or metabolized by the liver include:

  • amitriptyline (Elavil)
  • celecoxib (Celebrex)
  • clozapine (Clozaril)
  • cyclobenzaprine (Flexeril)
  • diazepam (Valium)
  • diclofenac (Voltaren)
  • fluvastatin (Lescol)
  • fluvoxamine (Luvox)
  • glipizide (Glucotrol)
  • haloperidol (Haldol)
  • ibuprofen (Advil, Motrin)
  • imipramine (Tofranil)
  • irbesartan (Avapro)
  • losartan (Cozaar)
  • mexiletine (Mexitil)
  • olanzapine (Zyprexa)
  • pentazocine (Talwin)
  • phenytoin (Dilantin)
  • piroxicam (Feldene)
  • propranolol (Inderal)
  • tacrine (Cognex)
  • tamoxifen (Nolvadex)
  • theophylline
  • tolbutamide (Tolinase)
  • torsemide (Demadex)
  • warfarin (Coumadin)
  • zileuton (Zyflo)
  • zolmitriptan (Zomig)
  • and others

Before taking kava talk to your doctor if you take any medications that are changed or metabolized by the liver.

Warning 3 – Sedative medications (CNS depressants): Because kava can cause drowsiness, taking it with CNS depressants may cause too much drowsiness. Experts recommend avoiding concurrent use. Examples of sedative medications include:

  • alprazolam (Xanax)
  • clonazepam (Klonopin)
  • lorazepam (Ativan)
  • phenobarbital (Donnatal)
  • zolpidem (Ambien)
  • and others

Warning 4 – Levodopa: Kava may decrease dopamine levels in the brain. Using kava while taking levodopa may decrease the effectiveness of levodopa.

Warning 5 – Activity: Kava is known to affect the ability to safely operate machinery. “Driving-under-the-influence” citations have been issued to people found driving erratically after drinking large amounts of kava tea.

Warning 6 – Surgery: Since kava affects the central nervous system it may increase the effects of anesthesia and other medications used during or after surgery. Experts recommend discontinuing use at least 2 weeks before a scheduled surgery.

Warning 7 – Antipsychotics: Using kava with these drugs may result in neuroleptic disorder.

Warning 8 – Barbiturates: When used with barbiturates Kava increases sedation.

Warning 9 – Antiparkinson medications: Kava increases the symptoms of Parkinson’s disease.

Warning 10 – Benzodiazepines: Kava increases sedation and may result in coma. Experts recommend avoiding concurrent use.

Warning 11 – Drug/herb interactions: Kava interacts with certain types of drugs, including, but not limited to, anticonvulsants, alcohol, and anti-anxiety medications. Consult with your doctor if you are using these types of drugs before using kava.

Used as a natural health remedy: kava is used externally for skin diseases including leprosy, to promote wound healing, and as a painkiller. It is also used as a mouthwash for toothaches and canker sores.

Used as a natural health remedy: kava is used internally for the following benefits:

  • Anxiety: The majority of evidence shows that certain kava extracts (kavalactones) can lower anxiety and might work as well as prescription anti-anxiety medications called benzodiazepines. This effect may take up to 8 weeks of treatment to see this benefit.
  • Kava may reduce withdrawal symptoms in people who are discontinuing anti-anxiety and sleep medicines called benzodiazepines. Slowly increasing the dosage of kava while decreasing the dosage of benzodiazepines over the course of 1 week seems to work for some people.
  • Kava decreases the anxiety in women going through menopause. Improvement can occur with as little as one week of treatment.

Although there is insufficient evidence to support the use of kava for the following, there are antidotal reports of benefits for:

  • Achy joints (rheumatism)
  • Attention deficit-hyperactivity disorder (ADHD)
  • Cancer prevention
  • Chronic bladder infections
  • Chronic fatigue syndrome (CFS)
  • Common cold and other respiratory tract infections
  • Depression
  • Epilepsy
  • Headaches
  • Insomnia
  • Leukemia
  • Menstrual discomfort and menopause (See other herbs for menopause)
  • Ovarian cancer
  • Psychosis
  • Respiratory tract infections
  • Restlessness
  • Sexually transmitted diseases
  • Social anxiety
  • Stress relief
  • Tuberculosis
  • Other conditions.

Side Effects of kava

The known side effects of using kava include:

  1. Chronic and heavy use of kava for more than 3 months has occasionally been reported to cause a scaly, yellow skin rash and an eye irritation that disappears after discontinuing use.
  2. Drinking exceptionally potent brews have been known to cause pronounced sleepiness into the next day.
  3. Long-term heavy use of kava is associated with elevated liver enzymes.
  4. Literature suggests that less than 0.5% of people who use kava have an allergic reaction to it. When rare allergic reactions do occur they are usually mild and include itchy skin or itchy throat, and hives on the skin usually on the user’s belly region.
  5. Liver toxicity
  6. Rash
  7. Vivid dreams

Other side effects may also occur when using kava. (See form below)

As with any herb, a serious allergic reaction is possible. Seek immediate medical attention if you notice any symptoms of a serious allergic reaction. These may include a rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.

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