Category

Synonyms

5- Hydroxytroptophan, Griffonia simplicifolia, L- 5- HTP, L- 5- Hydroxytroptophan, oxitriptan, Tript- OH®, tryptophan.

Note: Not to be confused with L- tryptophan.

Background

5- HTP is the precursor of the neurotransmitter serotonin. It is obtained commercially from the seeds of the plant Griffonia simplicifolia.

5- HTP has been suggested as a treatment for many conditions. There is some research to support the use of 5- HTP in treating cerebellar ataxia, headache, depression, psychiatric disorders, fibromyalgia, and as an appetite suppressant or weight- loss agent. There is not enough 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 reported side effects might result from contaminants in 5- HTP products.

Evidence

Cerebellar ataxia : Cerebellar ataxia results from the failure of part of the brain to regulate body posture and limb movements. 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.
Grade: B

Depression: 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.
Grade: B

Fibromyalgia: There is a small amount of research evaluating the use of 5- HTP for fibromyalgia, and early evidence suggests that 5- HTP may reduce the number of tender points, anxiety, and intensity of pain and may improve sleep, fatigue, and morning stiffness.
Grade: B

Headaches: There is evidence from several studies in both children and adults that 5- HTP may be effective in reducing the severity and frequency of headaches, including tension headaches and migraines. Further research is needed.
Grade: B

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

Alcoholism (withdrawal symptoms): Early study suggests that 5- HTP may lessen alcohol withdrawal symptoms. Further research is needed to confirm these results.
Grade: C

Anxiety: Although 5- HTP has been proposed as a possible treatment for anxiety disorders, there is not enough human evidence to make a firm recommendation.
Grade: C

Down's syndrome: Preliminary study of 5- HTP in children with Down's syndrome yields insignificant results. Further research is necessary.
Grade: C

Neurologic disorders (Lesch- Nyhan syndrome): Lesch- Nyhan syndrome (LNS) is a rare, genetic disorder affecting mostly males that often causes mental retardation and self- mutilation. Small studies of 5- HTP in Lesch- Nyhand syndrome show conflicting results. Additional study is needed.
Grade: C

Psychiatric disorders: It has been suggested that 5- HTP may reduce psychotic symptoms and mania or aid in panic disorder, but studies in people with schizophrenia have shown differing results.
Grade: C

Sleep disorders: There is insufficient evidence regarding the use of 5- HTP for sleep disorders. Additional studies are needed before a conclusion can be drawn.
Grade: C

Seizures/ epilepsy (myoclonic disorders): 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.
Grade: D