What are the risks and benefits of using kava for anxiety or insomnia?

Kava Risks and Benefits for Anxiety and Insomnia

Kava should not be used for anxiety or insomnia due to its lack of proven efficacy and significant risk of acute fatal liver toxicity, as the U.S. Food and Drug Administration has issued warnings about the risk for acute liver damage and death associated with kava. 1

Efficacy for Anxiety and Insomnia

• Studies show no benefit of using kava to treat chronic insomnia disorder compared with placebo 1
• While some research suggests kava may have anxiolytic properties through mechanisms including enhanced GABA binding and calcium channel blockade, the evidence is insufficient to support its use over established treatments 2
• A 2013 study showed moderate efficacy for kava in generalized anxiety disorder, but this single study is outweighed by safety concerns and lack of consistent evidence 3
• A small pilot study suggested potential benefits for stress-induced insomnia, but the sample size was limited and further research is needed 4

Safety Concerns

Liver Toxicity

• The U.S. Food and Drug Administration has warned healthcare providers and the public about the risk for acute liver damage and death associated with kava 1
• Multiple cases of severe liver toxicity associated with kava intake have been reported in Europe and the US 2

Perioperative Risks

• Kava should be held for at least 2 weeks before surgery due to its potential for:
  • Central nervous system depression that may act additively or synergistically with anesthetics, benzodiazepines, and opiates 1
  • Decreased blood flow to the kidneys potentially via inhibition of cyclooxygenase 1
  • Significant inhibition of multiple cytochrome P450 enzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP4A9/11) leading to drug interactions 1

Neurological Effects

• Kava intoxication can cause ataxia, tremors, sedation, blepharospasm, and elevated liver enzymes 5
• Saccadic abnormalities suggest disruption of cerebellar and GABAergic functions 5
• At high recreational doses (approximately 150 times clinical doses), kava causes significant impairment of movement coordination and visual attention 5

Clinical Decision Making

For Anxiety:

• First-line treatments should include evidence-based psychotherapy (such as cognitive behavioral therapy) and/or FDA-approved medications with established safety profiles 1
• Kava should not be recommended due to the FDA warnings about liver toxicity 1

For Insomnia:

• Cognitive Behavioral Therapy for Insomnia (CBT-I) is strongly recommended as first-line treatment 1
• If pharmacotherapy is needed, FDA-approved medications with established safety profiles should be considered before any herbal remedies 1
• Kava has a "strong against" recommendation for insomnia treatment in clinical practice guidelines 1

Special Considerations

• Patients with pre-existing liver conditions should absolutely avoid kava 2
• Patients taking medications metabolized by cytochrome P450 enzymes should be warned about potential interactions 1
• Patients undergoing surgery should discontinue kava at least 2 weeks prior to the procedure 1
• Patients should be informed that kava products may vary significantly in composition and quality, further increasing unpredictability of effects and risks 2, 6