Moxidectin. Protects your horse from reinfection of strongyles twice as long as other leading dewormer, up to 84 days. Treatments every 3 months will control worms and bots continually. QUEST controls encysted small strongyles in a single dose. Quest is effective against large and small strongyles, roundworms, pinworms, hairworms, bots and encysted small strongyles. A clear gel single dose syringe that treats an 1150 lb horse.