Compound or practice · Supplement
Tongkat Ali
The testosterone-support herb with the least-bad evidence — modest free-T and stress signals, best in the stressed or older.
- Overall grade
- Grade C
- Last revised
- 3
- graded outcomes
- 0
- references listed
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
3 at grade C — 3 graded rows
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Free testosteroneEvidence grade C
Larger in stressed/older
Smallmixed
- Stress / cortisolEvidence grade C
Modest
Smallmixed
- LibidoEvidence grade C
Subjective
Smallmixed
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Free testosterone (grade C); Stress / cortisol (grade C); Libido (grade C).
Interactions
Documented pairings with supplements and medicines. A medicine on this list is a conversation for whoever prescribes it.
The evidence in words
What it is
Tongkat ali (Eurycoma longifolia) is a standardized root extract (often to eurycomanone) used for testosterone, libido, and stress.
How it works
It appears to lower sex-hormone-binding globulin (freeing testosterone) and reduce cortisol, plausibly improving the testosterone-to-cortisol ratio under stress.
What the evidence shows
Small trials show modest increases in free testosterone, improved stress markers, and libido, with larger effects in stressed, older, or hypogonadal men than in healthy young men. It is the best-supported of a weak category — an experiment with an end date, not a default.
How to use it
200–400 mg/day of a standardized extract; assess over 4–8 weeks.
Safety & interactions
Generally tolerated; long-term safety and heavy-metal contamination of poor products are concerns — buy tested brands. Zinc — Free-T support assumes zinc sufficiency. Boron — Common free-testosterone support stack.
Bottom line
If you're going to trial a testosterone-support herb, this is the one — 200–400 mg standardized, most likely to help if you're stressed or older. Gate the trial on a lab and buy a tested product.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Standard
- 200–400 mg/day standardized, 4–8 week trial.
Goes with
Related reading
Entries that share this one's tags or conditions.
- Tongkat Ali for LibidoEvidence grade C — SubjectiveEvidence grade C
- FenugreekA libido herb with reasonable sexual-function data and inconsistent testosterone claims — the effect people feel is desire, not androgens.Evidence grade C
- Fenugreek for TestosteroneEvidence grade C — InconsistentEvidence grade C
- Tongkat Ali for Free testosteroneEvidence grade C — Larger in stressed/olderEvidence grade C
Sources
This entry lists no references of its own.
Last revised . A grade is this entry's reading of the evidence, not medical advice.