Comparison guide
L-tryptophan or 5-HTP?
L-tryptophan is the dietary amino acid; 5-HTP is the next step on the route to serotonin. They differ in dose and in what little they are supported for, but they share the same serious hazard: serotonin syndrome when combined with serotonergic drugs.
The options, compared
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| L-Tryptophan | Moderate evidence | Night-time waking | Doses above 1 g before bed moderately reduce time awake during the night, but antidepressant evidence is old and low quality; take it away from protein and buy third-party tested product. | View |
| 5-HTP | Limited evidence | No well-supported use | Mood, fibromyalgia, migraine and appetite claims rest on few, small, dated studies, and nausea is common and dose-limiting. | View |
Our verdict
Both are weakly supported; L-tryptophan needs larger doses but at least has moderate evidence for reducing night-time wakefulness, while 5-HTP skips a conversion step without a better evidence base. Do not take either with SSRIs, SNRIs, MAOIs, triptans, tramadol, lithium or other serotonergic drugs.