About Lapacho
Active naphthoquinones: lapachol and beta-lapachone, plus quinones and flavonoids. Mechanistic and in vitro evidence for antifungal (Candida), antibacterial, antiparasitic, and antitumor activity is reasonably extensive — beta-lapachone is studied as an oncology drug candidate (ARQ-501). However, human RCT evidence in dietary-supplement use is essentially absent. A 1970s NCI Phase I trial of isolated lapachol for cancer was terminated due to coagulation toxicity (anti-vitamin-K activity) at doses required for any antitumor effect, with no efficacy demonstrated. SAFETY: lapachol has documented anti-vitamin-K activity — significant additive bleeding risk with warfarin, DOACs, antiplatelets, NSAIDs; high doses cause nausea, vomiting, and hemolytic anemia. Avoid in pregnancy (teratogenic in animal studies) and in patients with bleeding disorders. The gap between marketing claims (immune, anti-cancer, anti-Candida) and human evidence is large.
What Lapacho supports
- Long traditional South American use; modern human RCT evidence is essentially absent
- Lapachol has anti-vitamin-K activity — meaningful bleeding risk with anticoagulants
How much Lapacho to take
The RDA prevents deficiency. The effective range is what clinical trials used to actually move the outcome.
Effective
1000–3000
mg
Traditional decoction-equivalent range; no rigorous human dose-finding studies exist. There is no validated therapeutic dose for any indication. Range tightened to reflect that the evidence base is even weaker than dong quai's — sub-1g doses are folk-symbolic.
Clinical evidence
Limited clinical evidence. Mechanistic/in vitro and animal data for naphthoquinones; no quality human RCTs supporting dietary supplement claims. NCI lapachol Phase I (Block et al. 1974) terminated for toxicity without efficacy.
Reference