(Merck) 10% Fenbendazole paste. Panacur Equine Dewormer Paste 10% contains the active anthelmintic, fenbendazole. Each gram of Equine Dewormer Paste 10% contains 100 mg Fenbendazole. Panacur equine dewormer paste is used for the safe and effective control of large and small strongyles, encysted early third stage, late third stage and fourth stage cyathostome larvae, pinworms and ascarids. Safe for pregnant mares, stallions, and foals. Apple cinnamon flavored. 25 gm tube.