Horny Goat Weed for Health & Longevity - Quick Reference Sheet

Horny Goat Weed for Health & Longevity

Created on 07/28/2026 – Quick Reference based on Evidence Review created using AI4L / Opus 4.8 Audit

A long-used herb with genuine biological activity but thin human evidence for longevity. Its strongest support is modest bone-strength help in older adults, from small, lower-quality trials. Sexual and broader heart, brain, and anti-inflammatory claims rest mainly on lab and animal work. Product quality is inconsistent, and absorption varies widely between people. (Full Review)

Protocol

Dose
250–1,000 mg/day
Standardized extract, sometimes divided
Standardization
5–20% icariin
Or 3–9 g dried herb as decoction
Timing
Daytime
Morning/early afternoon; split higher intakes
Time to effect
Bone & systemic
Weeks–months
Mirrors 3+ month trial durations
Sexual function
Variable
Acute, unreliable onset

Benefits

Contraindications
  • Hormone-sensitive cancers (breast, uterine, ovarian, prostate)
  • Endometriosis
  • Pregnancy or breastfeeding
  • Bleeding disorders or anticoagulation
  • Liver disease
  • Severe cardiac arrhythmia or heart failure (NYHA Class III–IV)
  • Surgery within 1–2 weeks
Key Interactions
  • Nitrates & PDE5 inhibitors (sildenafil, tadalafil, vardenafil)
  • Antihypertensives (ACE inhibitors, calcium-channel blockers, beta-blockers)
  • Anticoagulants & antiplatelets (warfarin, apixaban, aspirin, clopidogrel)
  • CYP3A4 drugs (simvastatin, ketoconazole, ritonavir, grapefruit juice)
  • Antiarrhythmic drugs
  • Hormone therapy & anti-estrogens (estrogen replacement, tamoxifen)
  • Antidepressants & mood stabilizers
  • BP-lowering supplements (L-arginine, L-citrulline, beetroot, garlic, CoQ10, magnesium)
  • Bleeding-risk supplements (fish oil, ginkgo, vitamin E)
  • Other phytoestrogens (soy isoflavones, red clover)

Risk & Side Effects

  • High:
  • Medium: Mild gastrointestinal & autonomic effects; product quality, adulteration & contamination
  • Low: Cardiovascular & arrhythmia effects; estrogenic/hormone-sensitive risk; rhabdomyolysis & muscle spasms; bleeding risk
  • Speculative: Hepatotoxicity; mood elevation & hypomania

Monitoring

Marker Target Why
Liver enzymes (ALT, AST) ALT ~10–26 U/L; AST ~10–26 U/L Screen for herbal liver stress
Blood pressure <120/80 mmHg Herb dilates vessels; watch for lows
Resting heart rate ~50–70 bpm High doses linked to palpitations
Creatine kinase (CK) ~30–150 U/L Detect rare muscle injury
Estradiol Men ~10–30 pg/mL; women per menopausal status Reflects phytoestrogen activity
Testosterone (total) Men ~500–900 ng/dL Tracks reproductive/sexual-health goal
Bone mineral density (DEXA T-score) T-score > −1.0 Primary endpoint for bone-health use
High-sensitivity C-reactive protein (hs-CRP) <1.0 mg/L Tracks systemic inflammation

Cadence: Blood pressure & heart rate at 2–4 weeks; liver enzymes ~3 months if continuous; bone density every 1–2 years; sex-hormone/symptom review at 3–6 months

Qualitative Assessment

  • Sexual function and libido
  • Energy and sense of vitality
  • Mood and stability
  • Joint and back comfort
  • Sleep quality