Eurycoma Longifolia

Best for

Boost testosterone levels

Large effect, needs confirmation · 100–600 mg/day for 1–12 weeks · 1 meta-analysis , n=302

10 papers · 5 claims · 38 outcomes scored · 3 positive

Outcomes

What eurycoma longifolia actually does, by outcome

Each row is one outcome with effect size, evidence base, the dose that worked in trials, and time to first effect. Magnitude tiers come from native-unit MCID where available, Cohen's d otherwise.

Outcome Effect size Evidence Dose Weeks Rank

Boost testosterone levels Large effect, needs confirmation

Raises total or free testosterone, especially when baseline runs low.

5 meta-analyses n=302 100–600 mg 1–12 wk #1/12

23243445·23705671·34262417·36013514 +1 more

large

5 meta-analyses n=302 Meta-analyzed I²=89%

100–600 mg

1–12 wk

#1 /12

Improve erection quality Promising early signal

Blood flow and nerve signaling work together instead of fighting you.

2 meta-analyses n=241 200–300 mg 12 wk #4/8

23243445·26365449

moderate

2 meta-analyses n=241 Meta-analyzed I²=90%

200–300 mg

12 wk

#4 /8

Build stronger muscles Promising early signal

Higher one-rep max, stronger grip, and more force from every muscle group.

2 RCTs n=161 200–300 mg 12 wk #9/38

23243445·34262417

moderate

2 RCTs n=161

200–300 mg

12 wk

#9 /38

Last longer before giving out Probably doesn't help

More reps, more miles, and a higher ceiling before fatigue forces you to stop.

2 meta-analyses n=290 400 mg 1 wk

34129223·37398958

small

2 meta-analyses n=290 Meta-analyzed

400 mg

1 wk

—

Increase sexual desire Not enough research

Raises interest in sex and responsiveness to sexual cues.

1 RCT n=— 300 mg 12 wk

23243445

—

1 RCT n=—

300 mg

12 wk

—

Outcome	Effect	Evidence	Dose	Weeks	Rank
Boost testosterone levels Large effect, needs confirmation	large	5 meta-analyses n=302 Meta-analyzed	100–600 mg	1–12 wk	#1/12
Improve erection quality Promising early signal	moderate	2 meta-analyses n=241 Meta-analyzed	200–300 mg	12 wk	#4/8
Build stronger muscles Promising early signal	moderate	2 RCTs n=161	200–300 mg	12 wk	#9/38
Last longer before giving out Probably doesn't help	small	2 meta-analyses n=290 Meta-analyzed	400 mg	1 wk	—
Increase sexual desire Not enough research		1 RCT n=—	300 mg	12 wk	—

Buy well

Recommended Eurycoma Longifolia products

Real products that dose Eurycoma Longifolia where the research does, in a clean formulation, from brands we've audited. We only list ones we'd stand behind.

Chosen for adequate Eurycoma Longifolia dosing vs. the studied range, a clean formulation (grade A–C), and independent brand-quality audits. Not sponsored.

Risk profile

Adverse events and known drug interactions

Safety events

headache mild

gastrointestinal symptoms (constipation, dyspepsia, abdominal pain, flatulence, abdominal discomfort) mild

pruritus mild

fever mild

bloating mild

breast tenderness mild

flatulence mild

abdominal discomfort mild

Drug interactions

Propranolol moderate decreases concentration

Rosiglitazone moderate decreases concentration

Blood Glucose Lowering moderate unknown

Antineoplastic Agents moderate increases concentration

Lipid Modifying Agents moderate increases concentration

Blood Glucose Lowering moderate increases concentration

other moderate increases concentration

Antipsychotics moderate increases concentration

Paracetamol minor decreases effect

Co-studied with

Supplements that share evidence with eurycoma longifolia

Polygonum 10 shared outcomes · d=0.65
Vitaminc 5 shared outcomes · d=0.59
Vitamind 5 shared outcomes · d=0.59
Vitaminb1 5 shared outcomes · d=0.59
Riboflavin 5 shared outcomes · d=0.59
Pyridoxine 5 shared outcomes · d=0.59
Cyanocobalamin 5 shared outcomes · d=0.59
Folicacid Specific 5 shared outcomes · d=0.59
Vitaminb7 5 shared outcomes · d=0.59
Copper 5 shared outcomes · d=0.59
Iron 5 shared outcomes · d=0.59
Magnesium 5 shared outcomes · d=0.59
Manganese 5 shared outcomes · d=0.59
Selenium 5 shared outcomes · d=0.59
Zinc 5 shared outcomes · d=0.59
Calcium 5 shared outcomes · d=0.59

Sources

Generated August 14, 2026

Eurycoma Longifolia

What eurycoma longifolia actually does, by outcome

Recommended Eurycoma Longifolia products

Adverse events and known drug interactions

Supplements that share evidence with eurycoma longifolia

More evidence for Eurycoma Longifolia

The Bitter Root and the Balancing Act: Tongkat Ali's Journey from Jungle Tonics to Measured Evidence

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Metabolic health: evidence map across 82 supplements

Arginine

icariin

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Eurycoma Longifolia

Recommended Eurycoma Longifolia products

More evidence for Eurycoma Longifolia

NewThe Bitter Root and the Balancing Act: Tongkat Ali's Journey from Jungle Tonics to Measured Evidence

NewBest Supplements for Testosterone, Ranked by Evidence

NewMetabolic health: evidence map across 82 supplements

NewArginine

Newicariin

NewMaca

The Bitter Root and the Balancing Act: Tongkat Ali's Journey from Jungle Tonics to Measured Evidence

Best Supplements for Testosterone, Ranked by Evidence

Metabolic health: evidence map across 82 supplements

Arginine

icariin

Maca