Primex Equine Liquid Wormer is prescription strength (50 mg/ml) pyrantel pamoate. Use Primex Equine Liquid Wormer for the removal and control of large and small strongyles, pinworms and large roundworms in horses. Give 6 ml per 100 lbs. body weight. (75 ml treats one 1250 lb. horse.) Peppermint flavor. Safe for all horses, including pregnant mares and foals.