Evidence explainerTongkat ali
Does Tongkat Ali Work? Small, Short Trials and Mixed Results
Hormone levels rose in small, short trials, pooled questionnaire scores did not change overall, and one trial measured immune lab scores. Here is what each study measured.
Key takeaways
- In a 2-week trial of 32 healthy young men, 600 mg/day raised total and free testosterone more than placebo [1].
- A 2022 meta-analysis of 5 randomized trials found higher total testosterone (SMD 1.35); its abstract does not give the pooled number of men [2].
- Pooled sexual-function questionnaire scores from 2 trials (139 men) did not differ from placebo overall at 12 weeks [3].
- A 4-week trial of 200 mg/day found higher immune lab scores than placebo [4].
- A 2024 systematic review of 52 studies rated tongkat ali 'possibly effective' for raising total testosterone [5].
Safety at a glance
From our Tongkat ali monograph. Published interactions and cautions only, each with its source.
Interactions
- Propranolol. Taken together, 200 mg of a water-based extract lowered propranolol bioavailability (AUC) by 29% in 14 healthy young men.[4]
Who should be careful
- People taking propranolol or other heart medicines. Tongkat ali reduced propranolol absorption in a pharmacokinetic study.[4]
- Sexual-enhancement products. FDA warns that many products sold for sexual enhancement, male energy or stamina are contaminated with hidden drug ingredients, are sometimes falsely sold as dietary supplements, and can cause serious health problems.[7]
- Before you start. Talk to your pharmacist or clinician before adding this supplement, especially if you take prescription medicines, are pregnant or breastfeeding, or have a chronic health condition.[3]
The evidence, graded
Pulled from our monograph evidence tables. Grades follow our evidence-grading policy.
- Grade DImprovedTotal and free testosteroneTotal testosterone, free testosterone and estradiol rose more than with placebo; luteinising hormone, FSH and SHBG did not change.
- Grade CNo effectSexual-function questionnaire scores (IIEF-5)No significant overall difference from placebo in IIEF-5 change at 12 weeks (heterogeneity 89.5%); a subgroup with lower baseline scores improved by 2.15 points.
- Grade CImprovedImmune vigor scores and T-cell countsImmune vigor score, immunological grade and total, naive and CD4+ T-cell counts were higher than placebo at week 4. No severe adverse events.
Hormone results
In a placebo-controlled trial, 32 healthy men (mean age 24.4) took 600 mg/day of Eurycoma longifolia or placebo for 2 weeks [1]. Total testosterone, free testosterone and estradiol rose more in the supplement group, while luteinising hormone, follicle-stimulating hormone and SHBG did not change [1].
A 2022 review included 9 studies and pooled 5 randomized trials, finding higher total testosterone (SMD 1.352), including in a subgroup of men with low testosterone [2]. The authors say more research is needed [2].
A 2024 systematic review of 52 studies on 27 proposed testosterone boosters found that most did not raise total testosterone [5]. It rated tongkat ali, based on 3 studies, as possibly effective in healthy men and in men with late-onset low testosterone [5].
Sexual-function questionnaires
A 2015 meta-analysis pooled 2 trials (139 men) that used the IIEF-5, a 5-item erectile-function questionnaire [3]. At 12 weeks there was no significant overall difference from placebo (weighted mean difference 0.91; 95% CI −1.50 to 3.33), with high heterogeneity (I² 89.5%) [3].
In a subgroup with lower starting scores, scores improved by 2.15 points [3]. The authors call for more trials [3].
Immune lab scores
In a 4-week trial in middle-aged Japanese adults with lower immune-vigor screening scores, 200 mg/day of a standardised root water extract (Physta) was compared with a rice-powder placebo; 40 and 41 people were analysed [4].
Immune vigor score, immunological grade and total, naive and CD4+ T-cell counts were higher than placebo at week 4 [4]. These were lab scores and cell counts, not illness rates [4].
What the trials cannot tell you
The single-agent trials here lasted 2 to 4 weeks and enrolled a few dozen people each, so they say little about longer use [1][4]. Products also differ: only the immune trial named a standardised extract [4].
For safety and a known drug interaction, read tongkat ali side effects. The tongkat ali monograph has the graded table, and the fenugreek monograph covers another herb studied for hormone outcomes.
Quick answers
How long did the trials last?
The hormone trial lasted 2 weeks, the immune trial 4 weeks, and the pooled questionnaire results were measured at 12 weeks [1][4][3].
What doses were studied?
The trials cited here used 600 mg/day for 2 weeks and 200 mg/day for 4 weeks [1][4].
Does tongkat ali lower SHBG?
In the 2-week trial of young men, SHBG did not change [1].
Keep reading
Full monographs
Related articles
- Tongkat Ali Side Effects: Short Safety Data, a Drug Interaction and Tainted Products
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Browse the full Supplement & Nutrient Encyclopedia or all supplement articles.
References
- [1]The effect of Eurycoma Longifolia on the regulation of reproductive hormones in young males. Andrologia, 2021.
- [2]Eurycoma longifolia (Jack) Improves Serum Total Testosterone in Men: A Systematic Review and Meta-Analysis of Clinical Trials. Medicina (Kaunas), 2022.
- [3]Efficacy of Tongkat Ali (Eurycoma longifolia) on erectile function improvement: systematic review and meta-analysis of randomized controlled trials. Complement Ther Med, 2015.
- [4]Immunomodulation in Middle-Aged Humans Via the Ingestion of Physta Standardized Root Water Extract of Eurycoma longifolia Jack: A Randomized, Double-Blind, Placebo-Controlled, Parallel Study. Phytother Res, 2016.
- [5]Do "testosterone boosters" really increase serum total testosterone? A systematic review. Int J Impot Res, 2024.