5-hydroxytryptophan (5-HTP) is an amino acid. The body makes 5-HTP from tryptophan (an essential amino acid) and converts it to an important brain chemical known as serotonin. Tryptophan and 5-HTP dietary supplements help raise serotonin levels in the brain, which may have a positive effect on sleep, mood, anxiety, aggression, appetite, temperature, sexual behavior, and pain sensation.

It is important to note, however, that an outbreak of eosinophilic myalgia syndrome (EMS; a potentially fatal disorder that affects the skin, blood, muscles, and organs) caused by a contaminated batch of tryptophan led to the removal of all tryptophan supplements from the United States market in 1989. Although the manufacturing of 5-HTP is different from that of tryptophan, there is still concern that some 5-HTP supplements may contain similar contaminants. It is important to obtain dietary supplements from manufacturers that adhere to high quality standards. At least two organizations, NSF International and the United States Pharmacopeia (USP), offer programs that make sure manufacturers follow high quality practices. As a result, these manufacturers often indicate this information on their product labels.

5-HTP may be helpful in treating a wide variety of conditions related to low serotonin levels, including the following:

Depression

Low levels of serotonin in the brain can contribute to the development of depression. Many drugs prescribed for depression increase serotonin levels. Some studies indicate that 5-HTP may be as effective as certain antidepressant drugs in treating individuals with mild to moderate depression. Such individuals have shown improvements in mood, anxiety, insomnia, and physical symptoms.

Fibromyalgia

Although many factors can influence the stiffness, pain, and fatigue associated with fibromyalgia, evidence from several studies indicates that low serotonin levels may play a role in the development of this condition. 5-HTP has been shown to improve sleep quality and reduce pain, stiffness, anxiety, and depression in individuals with fibromyalgia.

Insomnia

Medical research indicates that supplementation with tryptophan before bedtime can induce sleepiness and delay wake times. Studies also suggest that 5-HTP may be useful in treating insomnia associated with depression.

Headaches

Some studies suggest that 5-HTP may be effective in children and adults with various types of headaches including migraines.

Obesity

There is some evidence that low tryptophan levels may contribute to excess fat and carbohydrate intake (which can result in weight gain). A study of overweight individuals with diabetes suggests that supplementation with 5-HTP may decrease fat and carbohydrate intake by promoting a feeling of satiety (fullness). Additional similar studies of obese men and women without diabetes found that supplementation with 5-HTP resulted in decreased food intake and weight loss.

5-HTP is not commonly available in food but the amino acid tryptophan, from which the body makes 5-HTP, can be found in turkey, chicken, milk, potatoes, pumpkin, sunflower seeds, turnip and collard greens, and seaweed.

5-HTP can be obtained in the diet (from the conversion of tryptophan) or in supplement form. 5-HTP supplements are made from extracts of the seeds of the African tree Griffonia simplicifolia. 5-HTP can also be found in a variety of multivitamin and herbal preparations.

Pediatric

There are no known scientific reports on the pediatric use of 5-HTP. Therefore, it is not currently recommended for children.

Adult

50 mg of 5-HTP taken one, two, or three times per day is generally recommended for most of the conditions discussed in the Uses section.

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable healthcare provider.

As mentioned previously, tryptophan use has been associated with the development of serious conditions such as liver and brain toxicity, and with eosinophilic myalgia syndrome (EMS), a potentially fatal disorder that affects the skin, blood, muscles, and organs. Such reports prompted the FDA to ban the sale of all tryptophan supplements in 1989. As with tryptophan, EMS has been reported in 10 people taking 5-HTP.

5-HTP may cause mild gastrointestinal disturbances including nausea, heartburn, flatulence, feelings of fullness, and rumbling sensations in some people. Pregnant or nursing women and individuals with high blood pressure or diabetes should consult a healthcare practitioner before taking 5-HTP.

In addition, as described in the Interactions section below, 5-HTP should not be taken at the same time as antidepressants.

If you are currently being treated with any of the following medications, you should not use 5-HTP without first talking to your healthcare provider.

Antidepressant Medications

Individuals taking the antidepressant medications known as selective serotonin reuptake inhibitors (SSRIs) (such as fluoxetine, paroxetine, sertraline, and citalopram) and monoamine oxidase inhibitors (MAOIs) (such as phenelzine, isocarboxazid, selegiline, and tranylcypromine) should not use 5-HTP as these medications enhance the action of these drugs and may increase the risk for developing a dangerous condition known as "serotonin syndrome." Serotonin syndrome is characterized by mental status changes, rigidity, hot flashes, rapidly fluctuating blood pressure and heart rate, and possibly coma. Similarly, other drugs for depression that interfere with the uptake of the neurotransmitter serotonin, namely trazodone and venlafexine, may also lead to serotonin syndrome when used along with 5-HTP.

Carbidopa

Taking 5-HTP with carbidopa, a medication used to treat Parkinson's disease, has been associated with side effects including scleroderma-like illnesses (a condition in which the skin becomes hard, thick, and inflamed).

Sumatriptan
Similar to antidepressants, sumatriptan, a medication used for migraine headaches that works by stimulating serotonin receptors in the brain, should also not be used in combination with 5-HTP because of the risk for serotonin syndrome.

Tramadol

Tramadol, used for pain control, may also increase serotonin levels too much if taken in combination with 5-HTP. Serotoninsyndrome has been reported in some people taking the two together.

Zolpidem

Use of zolpidem, a medication for insomnia, can cause hallucinations when used with SSRI antidepressants. Because 5-HTP may work similarly to SSRIs, the combination of 5-HTP with zolpidem could, theoretically, lead to hallucinations as well.

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