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:
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.
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.
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.
Some studies suggest that 5-HTP may be effective in children and adults with
various types of headaches including migraines.
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
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
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.
How to Take It
There are no known scientific reports on the pediatric use of 5-HTP.
Therefore, it is not currently recommended for children.
50 mg of 5-HTP taken one, two, or three times per day is generally
recommended for most of the conditions discussed in the
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.
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.
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, 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.
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
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Review Date: April 2002
Reviewed By: Participants in the review process include: Ruth DeBusk, RD, PhD, Editor,
Nutrition in Complementary Care, Tallahassee, FL; Jacqueline A. Hart, MD,
Department of Internal Medicine, Newton-Wellesley Hospital, Harvard University
and Senior Medical Editor Integrative Medicine, Boston, MA; Gary Kracoff, RPh
(Pediatric Dosing section February 2001), Johnson Drugs, Natick, Ma; Steven
Ottariono, RPh (Pediatric Dosing section February 2001), Veteran's
Administrative Hospital, Londonderry, NH. All interaction sections have also
been reviewed by a team of experts including Joseph Lamb, MD (July 2000), The
Integrative Medicine Works, Alexandria, VA;Enrico Liva, ND, RPh (August 2000),
Vital Nutrients, Middletown, CT; Brian T Sanderoff, PD, BS in Pharmacy (March
2000), Clinical Assistant Professor, University of Maryland School of Pharmacy;
President, Your Prescription for Health, Owings Mills, MD; Ira Zunin, MD, MPH,
MBA (July 2000), President and Chairman, Hawaii State Consortium for Integrative
Medicine, Honolulu, HI.
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regarding dosage, precautions, warnings, interactions, and contraindications
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