Durvet Duramectin Ivermectin Paste eliminates 35 species and stages of internal parasites, including bots and arterial stages of S. vulgaris, in a single dose. Safe for horses of all ages—mares at any stage of pregnancy and stallions without affecting fertility. The easy-to-use syringe delivers precise dosing: one syringe treats one 1250 lb horse, with weight markings on the plunger for accurate 250 lb increments. Provides effective parasite protection so your horse can reach full potential. Refer to package label for complete use directions.