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Herbal Extract

Longjack Extract (Eurycoma longifolia)

Also known as: Tongkat Ali, Eurycoma longifolia, Malaysian Ginseng, LJ100

B
Evidence

Longjack is a traditional Southeast Asian herb studied primarily for testosterone support and male fertility enhancement. Evidence suggests potential benefits for testosterone levels and sexual function in men, though quality of research varies.

Primary uses

  • Testosterone support
  • Male sexual function
  • Male fertility
  • Muscle strength and athletic performance

How it works

  • Bioactive alkaloids (eurycomanone) may modulate luteinizing hormone (LH) and testosterone production
  • Potential antioxidant and stress-reducing effects
  • May improve sperm quality and motility

Dosage

Typical range
200-400 mg daily (standardized extract containing 22% eurycomanone)
Timing
Typically taken once daily with meals
With food
Often taken with food to improve absorption and reduce GI upset
Duration
Most studies used 4-12 weeks; benefits may accumulate over 8+ weeks of consistent use
Special populations
Limited safety data in women and adolescents; not recommended during pregnancy or breastfeeding

Forms

  • Root extract powder· 70/100
  • Capsules· 70/100
  • Standardized extract· 70/100

Safety

Common side effects

  • Insomnia or sleep disturbances (in some users)
  • Mild gastrointestinal upset
  • Increased body temperature
  • Restlessness or increased energy

Contraindications

  • Pregnancy and breastfeeding
  • Hormone-sensitive cancers (theoretical concern; consult healthcare provider)
  • Men with prostate cancer or elevated PSA
  • Individuals on testosterone replacement therapy (additive effects possible)

Evidence notes

Multiple human RCTs demonstrate modest improvements in testosterone levels and sexual function in men; however, study quality varies, sample sizes are often small, and effects are inconsistent across populations. Strong tradition of use with reasonable mechanistic support justifies B grade rather than C.

Grade B: Some human trials support key claims; further confirmation needed.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.