Ivermectin Compounded oral liquid is an oil-based preparation. Ivermectin is a prescription medication that is used to treat and prevent heartworms in a variety of species. It can also be used to treat many other parasitic infections, including strongyles, ascarids, pinworms, and hookworms. Ivermectin Compounded oral liquid is made specifically for your pet. Please note, the doses of Ivermectin used for parasite treatment are much higher than those used for parasite prevention. The strengths of Compounded Ivermectin are intended for parasite treatment.