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5-Hydroxytryptophan (5-HTP) for Anxiety

An effective and safe natural treatment of anxiety.

The brain needs L-tryptophan and 5-hydroxytryptophan (5-HTP) to manufacture serotonin.

L-tryptophan and 5-HTP are widely used alternative treatments of generalized anxiety. Both amino acids are essential for the manufacturing of serotonin in the brain. Serotonin is a neurotransmitter that plays a central role in the regulation of mood and anxiety. Greater research evidence supporting the use of 5-HTP for anxiety, together with smaller effective doses and increased CNS availability, generally make 5-HTP the preferred choice over L-tryptophan.

5-HTP reduces the severity of generalized anxiety.

More research has been done on 5-HTP than l-tryptophan. In a double-blind study, 58 percent of generally anxious patients (79 total subjects) randomized to L-tryptophan 3 grams per day reported significantly greater reduction in baseline anxiety compared to individuals who received a placebo. Both animal studies and human clinical trials show that 5-HTP has anti-anxiety effects. There is some evidence that 5-HTP may also inhibit panic attacks induced by carbon dioxide.

The uses of 5-HTP in integrative psychiatry.

In the rapidly growing field of integrative psychiatry, prescription medications and natural supplements are often used in combination to improve treatment response and reduce side effects resulting when medications are taken alone. 5-HTP is an example of a natural supplement that may be safely combined with a prescription anti-anxiety medication with little risk of adverse effects. In one study, patients randomized to 5-HTP in combination with carbidopa (a drug that inhibits the enzyme that breaks down 5-HTP in the peripheral blood supply, thus increasing the amount of 5-HTP that enters the brain) reported reductions in anxiety comparable to patients treated with an anti-anxiety medication. In contrast, patients who received a placebo did not improve.

Starting 5-HTP at a low dose reduces the risk of side effects.

Some individuals who take 5-HTP report daytime fatigue or sleepiness. There have been infrequent reports of mild serotonin syndrome, a condition caused by excessive brain serotonin associated with insomnia, agitation, and nervousness. The risk of serotonin syndrome and other adverse effects is minimized when 5-HTP is started at low doses, such as 25 milligrams per day, and gradually increased over several weeks to a daily regimen that is well tolerated and produces beneficial anti-anxiety effects.

In over 20 years as an integrative psychiatrist, I have found that 5-HTP—50 milligrams to 100 milligrams taken three times a day—is a safe and effective approach for chronic generalized anxiety that is well tolerated without excessive daytime sedation. 5-HTP may be taken alone or in combination with anti-anxiety medications.

Taking 5-HTP at bedtime improves sleep and reduces daytime anxiety.

Gradually increasing a bedtime dose of 5-HTP from 50 milligrams to 200 to 300 milligrams over a period of two to three weeks often improves the quality of sleep in chronically anxious patients who complain of insomnia while also reducing the severity of daytime anxiety.

Find a quality brand of 5-HTP.

When considering taking 5-HTP or any natural supplement, it is important to find a brand known to be both effective and safe. I do not recommend particular brands to my patients. However, my website includes links to web resources that will help you identify quality brands.


"Anxiety: The Integrative Mental Health Solution" by James Lake M.D.

About the Author
James Lake, MD

James Lake, M.D., a clinical assistant professor at the University of Arizona College of Medicine, works to transform mental health care through the evidence-based uses of alternative therapies.

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