) Promectin B Pour-On is an ivermectin pour-on for treatment and control of parasites in cattle. Ivermectin pour-on is effective against roundworms, lungworms, grubs, horn flies, sucking and biting lice, and sarcoptic mange mites in cattle. Rain-fast after 6 hours. Promectin B Pour-On contains 5 mg ivermectin per ml. Apply to cattle along the topline in a narrow strip extending from the withers to the tailhead. Safe for pregnant cattle. Use at the rate of 1 ml per 22 lbs. body weight.