Is 5-HTP (5-Hydroxytryptophan) Safe with Selective Serotonin Reuptake Inhibitors (SSRIs)?
Free · No account · based on published sources including NIH ODS, FDA drug labels, and peer-reviewed literature
Do not combine SSRIs with 5-HTP supplements. If already taking both, discontinue 5-HTP and notify the prescribing clinician promptly.
Why this interaction occurs
SSRIs block the serotonin transporter (SERT), reducing serotonin clearance. 5-HTP increases serotonin synthesis as a direct precursor. The combination significantly elevates synaptic serotonin levels, increasing the risk of serotonin syndrome. Animal models with SERT deficiency (analogous to SSRI use) show exaggerated serotonin syndrome responses to 5-HTP.
Evidence
Evidence level: moderate.
Data source
PubMed - PMID 19275775
Reported safety data
The FDA’s adverse event reporting system (FAERS) has received 5,720,660 reports mentioning Selective Serotonin Reuptake Inhibitors (SSRIs). This reflects reported cases involving the medication in general — not confirmed causation, and not specific to the Selective Serotonin Reuptake Inhibitors (SSRIs) + supplement combination on this page.
FAERS reports are voluntary and cannot prove that a drug caused an event. Do not use report counts to assess the safety of this specific drug-supplement pair.
Frequently asked questions
Related interactions
All 5-HTP (5-Hydroxytryptophan) interactions → · All Selective Serotonin Reuptake Inhibitors (SSRIs) interactions →
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Educational only — not medical advice.
Always confirm with your doctor or pharmacist.