Ivermectin, Mebendazole & Fenbendazole to Treat Cancer - Quick Reference Sheet

Ivermectin, Mebendazole & Fenbendazole to Treat Cancer

Created on 07/04/2026 – Quick Reference based on Evidence Review created using AI4L / Opus 4.8 Audit

These cheap antiparasitic drugs disrupt several processes cancer cells rely on in laboratory and animal studies, and are widely available and generally well tolerated short-term. Human evidence stays weak — cell studies, patient stories, and one uncontrolled survey, with no completed randomized trials. Main concerns are liver strain, blood-count effects, and delaying proven treatment. (Full Review)

Protocol

Dosing
Ivermectin ~12–25 mg/day
Mebendazole ~100–250 mg/day or fenbendazole ~200–300 mg/day, six days per week
Administration
With a fatty meal
Ivermectin once daily; benzimidazoles split into 2–3 daily doses
Escalation
Start low, escalate slowly
Begin at the lower end of proponent ranges; guided by tolerance and labs
Time to effect
Apparent response
Weeks to months
No reliable timeframe; hard to attribute to the drugs
Reassessment block
~12 weeks
Proponent protocols run in defined blocks, then reassess

Benefits

Contraindications
  • Pregnancy and breastfeeding
  • Significant liver impairment (Child-Pugh Class B or C)
  • Baseline neutropenia or strongly myelosuppressive regimens
  • Young children
  • Substituting for potentially curative standard treatment
Key Interactions
  • Strong CYP3A4 inhibitors (ketoconazole, itraconazole, ritonavir, clarithromycin)
  • CYP3A4 inducers (rifampin, carbamazepine, phenytoin)
  • P-glycoprotein inhibitors (verapamil, quinidine, cyclosporine)
  • Warfarin
  • Acetaminophen and other liver-stressing drugs
  • Cimetidine
  • Liver-stressing supplements (high-dose niacin, green tea extract, kava)
  • Grapefruit
  • Additive supplements (high-dose vitamin C, vitamin D, zinc, curcumin, berberine)
  • Chemotherapy (additive myelosuppression)
  • Alcohol

Risk & Side Effects

  • High: Gastrointestinal effects; foregoing or delaying evidence-based treatment
  • Medium: Liver injury; bone-marrow suppression
  • Low: Neurological effects; product quality and contamination
  • Speculative: Unknown long-term effects of chronic high-dose use

Monitoring

Marker Target Why
ALT / AST ~10–26 U/L Detect drug-induced liver injury early
Bilirubin ~0.3–1.0 mg/dL Flags more significant liver stress
Neutrophils ~1.8–6.0 ×10⁹/L Detect bone-marrow suppression before infection risk
Platelets ~175–250 ×10⁹/L Screen for marrow suppression and bleeding risk
Albumin ~4.0–5.0 g/dL Marker of nutritional and liver status and overall reserve
C-reactive protein <1.0 mg/L Track systemic inflammation and tumor-related activity
Lactate dehydrogenase (LDH) ~140–200 U/L General marker of tumor burden and cell turnover

Cadence: Liver enzymes and complete blood count at baseline, ~4 weeks, then every 4–8 weeks during use (more often with chemotherapy); tumor imaging roughly every 3 months

Qualitative Assessment

  • Energy levels and daily functioning
  • Pain and use of pain medication
  • Appetite and unintentional weight change
  • Sleep quality
  • Cognitive clarity and mood
  • Tolerability of concurrent standard treatment