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L-tryptophan safety: the history, the interactions and the 9.5 mg ceiling
L-tryptophan safety hinges on two facts: a 1989 outbreak of eosinophilia-myalgia syndrome was traced to contaminated supplements, and the amino acid clashes with several drug classes. Payarmin lists L-tryptophan 21st of 22 in a 200 mg blend, so at most 9.5 mg per 1 mL serving.
Written by the Payarmin meter deskUpdated · 4 min read
Is L-tryptophan safe to take?
It carries a history. In 1989, manufactured L-tryptophan supplements were linked to an outbreak of eosinophilia-myalgia syndrome, and FDA issued a nationwide warning and recall that November (NORD, Eosinophilia-Myalgia Syndrome).
| People affected | More than 1,500 |
|---|---|
| Deaths attributed | 37 |
| Source | Nearly all traced to one manufacturer |
The cause was contamination in particular products, not the amino acid alone. It is still why careful readers ask who makes a supplement and where.
How much L-tryptophan is in Payarmin?
At most 9.5 mg per 1 mL. Line 21 can weigh no more than 200 / 21 (21 CFR 101.36 (eCFR)).
That sits close to the even-split share of 9.09 mg per line. Only the last line, L-carnitine, has a lower ceiling, 9.1 mg. The floor for line 21 is 0, since a line may weigh almost nothing.
The label does not name the manufacturer; it lists Instituto Experience as distributor and an FDA registered facility. Registration is not approval (FDA, Registration of Food Facilities guide).
What medicines clash with L-tryptophan?
Do not use it without medical advice alongside MAO inhibitors, tramadol, dextromethorphan, meperidine or sedatives (Drugs.com, L-tryptophan).
- Other serotonin-raising supplements, such as 5-HTP and St. John's wort, belong on the same list.
- It is considered likely unsafe in pregnancy.
- Cough syrups often hide dextromethorphan. Check the label.
A supplement does not replace it. Never change a dose on your own.
Payarmin: from $49 a bottle30 mL · 2, 3 or 6 bottles · free US shipping on 3 and 6 · 60-day results-or-refund guarantee
See packsWhat is the practical reading for Payarmin users?
A very small share, with real interaction rules: if you take any drug above, ask a pharmacist before the drops.
See the amino acid page, the Supplement Facts panel and side effects. We know of no store listing; the official checkout is where to order.
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FAQ01
L-tryptophan: quick answers
Does the 1989 recall apply to Payarmin?
The outbreak was tied to specific contaminated products, nearly all from one manufacturer (NORD, Eosinophilia-Myalgia Syndrome). We found no link to Payarmin, but its manufacturer is not named on the label.
Is L-tryptophan the same as 5-HTP?
No. Both raise serotonin, though, and the interaction guidance lists 5-HTP among the supplements to avoid combining with L-tryptophan without advice (Drugs.com, L-tryptophan).
Can I take Payarmin with an antidepressant?
Ask your prescriber or pharmacist first. L-tryptophan should not be combined with MAO inhibitors or other serotonin-raising drugs without advice (Drugs.com, L-tryptophan).
Who wrote this02
Written and reviewed by
Pages built from the label, the sales page and linked NIH, FDA, CDC, FTC and peer-reviewed sources.
Last updated . Read our editorial standards, and the way we check reviews. This website is a U.S. retail partner for Payarmin, not the manufacturer or the label's distributor. Buying through our order links earns us money.
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