5-HTP

Related Terms

5-Hydroxytroptophan, Griffonia plant seed extract, Griffonia simplicifolia, L-5-HTP, L-5-hydroxytroptophan, Natrol? 5-HTP, Natural Factors? 5-HTP, oxitriptan, serotonin, Tript-OH?, tryptophan.
Select combination products: GabadoneT (5-HTP, tryptophan, and other amino acids), Nature's Way 5-HTP (5-HTP, vitamin B6, vitamin C), Natural Factors? Tranquil Sleep (5-HTP, melatonin, L-theanine).
Note: 5-HTP should not to be confused with L-tryptophan.

Background

5-HTP is the precursor of the neurotransmitter serotonin. Commercially available 5-HTP is obtained from the seeds of the plant Griffonia simplicifolia.
5-HTP has been suggested as a treatment for many conditions. Some research supports the use of 5-HTP in treating cerebellar ataxia, headache, depression, psychiatric disorders, and fibromyalgia, and as an appetite suppressant or weight loss agent. There is insufficient scientific evidence to support the use of 5-HTP for any other medical condition.
5-HTP may cause gastrointestinal disturbances, mood disturbances, seizure, or abnormal blood counts. Some side effects might result from contaminants in 5-HTP products.

Evidence Table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *


5-HTP has been observed to have benefits in some people who have difficulty standing or walking because of cerebellar ataxia. However, current evidence is mixed.

 B


5-HTP has been observed to have benefits in some people who have difficulty standing or walking because of cerebellar ataxia. However, current evidence is mixed.

 B


Studies suggest that 5-HTP may reduce eating behaviors, lessen caloric intake, and promote weight loss in obese individuals.

 B


Studies suggest that 5-HTP may reduce eating behaviors, lessen caloric intake, and promote weight loss in obese individuals.

 B


Early research suggests that 5-HTP may lessen alcohol withdrawal symptoms. Further research is needed before a conclusion can be made.

 C


Early research suggests that 5-HTP may lessen alcohol withdrawal symptoms. Further research is needed before a conclusion can be made.

 C


Although 5-HTP has been proposed as a possible treatment for anxiety disorders, sufficient human evidence to make a firm conclusion is lacking.

 C


Although 5-HTP has been proposed as a possible treatment for anxiety disorders, sufficient human evidence to make a firm conclusion is lacking.

 C


The results of numerous studies in humans suggest that 5-HTP may aid in the treatment of depression. However, it is not known whether 5-HTP is as effective as commonly prescribed antidepressant drugs.

 C


The results of numerous studies in humans suggest that 5-HTP may aid in the treatment of depression. However, it is not known whether 5-HTP is as effective as commonly prescribed antidepressant drugs.

 C


Preliminary research on 5-HTP in children with Down's syndrome has yielded insignificant results. Further research is necessary.

 C


Preliminary research on 5-HTP in children with Down's syndrome has yielded insignificant results. Further research is necessary.

 C


There is a small amount of research evaluating the use of 5-HTP for fibromyalgia. Early evidence suggests that 5-HTP may reduce the number of tender points, anxiety, and the intensity of pain, and may improve sleep, fatigue, and morning stiffness. Further research is needed before a conclusion can be made.

 C


There is a small amount of research evaluating the use of 5-HTP for fibromyalgia. Early evidence suggests that 5-HTP may reduce the number of tender points, anxiety, and the intensity of pain, and may improve sleep, fatigue, and morning stiffness. Further research is needed before a conclusion can be made.

 C


Several studies, in both children and adults, suggest that 5-HTP may be effective in reducing the severity and frequency of headaches, including tension headaches and migraines. Further research is needed.

 C


Several studies, in both children and adults, suggest that 5-HTP may be effective in reducing the severity and frequency of headaches, including tension headaches and migraines. Further research is needed.

 C


In early research, 5-HTP lacked an effect on mood in healthy, young subjects. However, in this population, 5-HTP may impair decision-making. Further well-designed research is needed.

 C


In early research, 5-HTP lacked an effect on mood in healthy, young subjects. However, in this population, 5-HTP may impair decision-making. Further well-designed research is needed.

 C


5-HTP has been studied in panic disorder and various neurologic disorders. Additional clinical research is needed before conclusions can be made.

 C


5-HTP has been studied in panic disorder and various neurologic disorders. Additional clinical research is needed before conclusions can be made.

 C


Parkinson's disease is a neurological disorder that usually develops around the age of 50. The disorder occurs when the brain cells that make dopamine slowly degenerate. Symptoms include tremors (shaking) and difficulties with movement and coordination. 5-HTP has been studied, usually in combination with drugs, for Parkinson's disease.

 C


Parkinson's disease is a neurological disorder that usually develops around the age of 50. The disorder occurs when the brain cells that make dopamine slowly degenerate. Symptoms include tremors (shaking) and difficulties with movement and coordination. 5-HTP has been studied, usually in combination with drugs, for Parkinson's disease.

 C


It has been suggested that 5-HTP may reduce psychotic symptoms and mania in panic disorder, but studies in people with schizophrenia have shown mixed results.

 C


It has been suggested that 5-HTP may reduce psychotic symptoms and mania in panic disorder, but studies in people with schizophrenia have shown mixed results.

 C


Insufficient evidence is currently available regarding the use of 5-HTP for sleep disorders. Additional studies are needed before a conclusion can be drawn.

 C


Insufficient evidence is currently available regarding the use of 5-HTP for sleep disorders. Additional studies are needed before a conclusion can be drawn.

 C


Limited research suggests that 5-HTP may be ineffective for reducing hot flash frequency in postmenopausal women. Further research is required before firm conclusions can be drawn.

 D


Limited research suggests that 5-HTP may be ineffective for reducing hot flash frequency in postmenopausal women. Further research is required before firm conclusions can be drawn.

 D


Although 5-HTP has been studied as a treatment for various myoclonic syndromes and epilepsy, available research does not support the use of 5-HTP for these conditions.

 D


Although 5-HTP has been studied as a treatment for various myoclonic syndromes and epilepsy, available research does not support the use of 5-HTP for these conditions.

 D
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory

The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

Adults (18 years and older)
For cerebellar ataxia, 10-16 milligrams per kilogram of body weight has been taken by mouth daily.
For depression, 200-300 milligrams has been taken by mouth daily.
For fibromyalgia, 100 milligrams has been taken by mouth three times daily.
For headache, 300-600 milligrams has been taken by mouth daily in divided doses.
For hot flashes, 150 milligrams has been taken by mouth daily for four weeks.
For mood, 50 milligrams has been taken by mouth in two separate doses.
For obesity, eight milligrams per kilogram of body weight or 750-900 milligrams has been taken by mouth daily.
For psychiatric disorders, 25-350 milligrams has been taken by mouth daily for anxiety.
For seizures or epilepsy (myoclonic disorders), 15 milligrams per kilogram of body weight has been taken by mouth daily, in combination with carbidopa, for 14 days to one month.
For sleep disorders, 100 milligrams has been taken by mouth at 7:30 p.m., followed by 200 milligrams at 9:00 p.m. for five nights.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Interactions

Interactions with Drugs
Note: 5-HTP is a precursor to serotonin; thus, it may interact with agents that modulate levels of serotonin.
5-HTP may cause low blood pressure. Caution is advised in patients taking drugs that lower blood pressure.
5-HTP may interfere with the way the body processes certain drugs using the liver's cytochrome P450 enzyme system. As a result, the levels of these drugs may be increased or decreased in the blood, and may cause increased or decreased effects or potentially serious adverse reactions. Patients using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
5-HTP may increase the amount of drowsiness caused by some drugs. Examples include benzodiazepines such as lorazepam (Ativan?) or diazepam (Valium?), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.
5-HTP may interact with angiotensin-converting enzyme receptor blockers (ARBs), antianxiety agents (such as buspirone and trazodone), anticancer agents, antidepressants (including monoamine oxidase inhibitors [MAOIs] such as L-deprenyl, selective serotonin reuptake inhibitors [SSRIs], serotonin and norepinephrine reuptake inhibitors [SNRIs] such as venlafaxine, tetracyclics such as mirtazapine, or tricyclics [TCAs]), anti-inflammatories, antiobesity agents (such as phentermine), antiseizure agents, antipsychotic agents (such as haloperidol), barbiturates (such as pentobarbital), benzodiazepines, benzylpiperazine, cannabinoids (such as tetrahydrocannabinol), cholesterol-lowering agents, CNS depressants, decarboxylase inhibitors (such as carbidopa and benserazide), diltiazem, drugs that lower seizure threshold, growth hormones, hormonal agents, lithium carbonate, losartan, methamphetamine, metoclopramide, painkillers, sedatives, serotonin receptor antagonists (such as methysergide, nefazodone, cyproheptadine, and ritanserin), or thyroid hormones.

Attribution

This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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