Duramectin Paste (1.87% Ivermectin) Wormer 0.21 oz is a highly-effective equine parasite control solution designed to treat parasitic worms in horses. It contains 1.87% ivermectin, an ingredient known for its efficacy in eliminating and controlling worms, bots, and other harmful parasites. It's easy to administer and provides reliable and long-lasting protection for horses.