Is there a convention about how it is best for humans to take 5-HTP?

Question

5-HTP is an amino acid derivative from tryptophan acting as the direct precursor for the neurotransmitter serotonin (5-HT) and hence of melatonin in mammals.
It is found in different foods in insignificant amount but in some particular foods in a significant amount for extraction, as in Griffonia simplicifolia.
It is available as a dietary supplement.

Is there a convention about how it is best for humans to take 5-HTP?

_{For example, at what time of day, drug interactions to avoid, etc, to increase serotonin levels in an otherwise healthy person, in cases of indication (perhaps emotional eating or recovering from some form of depression).}

Answer 1

5-HTP is used by physicians a broad usage but recent clinical trials doesn't come up with appropriate general guidelines for its dosage, so, no, as of February 2020, there isn't a convention.

Usage Examples:

• 600 mg of 5-HTP was given to the patients and there was significant increase in the sleep quality with increase in REM sleep. While patients using smaller doses of 200mg showed lesser degree of improvement in sleep quality. For insomnia, the dosage should be between 100-300 mg before the bedtime. It can cause nausea in some patients, so treatment with 5-HTP, should be started with 50 mg doses. (Via: http://www.altmedrev.com/archive/publications/3/4/271.pdf )

• Treatment of children with 5- HTP regulates the sleep cycle and this shows improvement in long-term sleep terrors (Via: https://link.springer.com/article/10.1007%2Fs00431-004-1444-7).

• 5-HTP is absorbed well when taken orally, approximately 70% enters the bloodstream. Therapeutic administration of 5-HTP is used in treatment of depression, fibromyalgia and insomnia. (https://www.ncbi.nlm.nih.gov/pubmed/9727088).

• The 5-HTP toxicity is reported at higher concentrations of serotonin in the central nervous system. Various cases are reported of heart valve damage when taken with serotonin reuptake inhibitors or monoamine oxidase inhibitors ( https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/5-hydroxytryptophan).

• Taking more than required amount of 5-HTP is harmful for body. As 5-HTP bypass the feedback loop of serotonin pathway and leads to its accumulation.

Further reading

This link contains user reviews & ratings opinions about the effectiveness of 5-HTP usage in various health issues.