Most fenbendazole never reaches tumours — poor absorption is the #1 problem. This 2026 deep-dive covers exactly how fat increases bioavailability 1.6–2.8x, the science behind Vitamin E succinate, curcumin, berberine and CBD, cancer-type evidence for colorectal (strongest), lung, and prostate, a 3-benzimidazole comparison table, and 3-on-4-off vs daily dosing compared.