Safety

Theoretical concerns do exist regarding the safety of 5-HTP and an unknown contaminant called "peak X" that has been found in some batches of 5-HTP. Patients may ask about this, and the story is as follows:

There were a number of severe and even lethal cases of Eosinophilia-Myalgia Syndrome (EMS) that occurred in users of tryptophan (not 5-HTP) marketed as a sleep aid in the late 1980s; after a thorough investigation the problem was traced to a change in manufacturing process by a Japanese company that produced 60% of the tryptophan sold in the US. Tryptophan was then taken off the market evevn though the EMS was related only to the single Japanese product. Chemical analysis found a "peak E" similar to "peak X" in the contaminated samples. Peak E is presumed to have been the cause of the EMS but this is not known for sure.

Tryptophan and 5-HTP are obviously related chemicals, but different manufacturing processes are used to create each product as tryptophan was produced using a bacterial fermentation process and 5-THP is produced from the seeds of the Griffonia simplicifolia plant.

There have been no reported cases of EMS among 5-HTP users although asymptomatic eosinophilia had been reported in two patients almost 20 years ago prompting an FDA warning. There have been no further reports of this problem.

Patients should be reassured that the EMS risk at this point in time when using 5-HTP is very, very low, and likely nonexistent.