 Acetazolamide ("Acet") is used for treating horses with the genetic disease hyperkalemic periodic paralysis (HYPP), and prevents affected animals from having seizures.Acet is only allowed for horses that test positive for HYPP and have HYPP status noted on their registration papers.The ApHC recommends that Appaloosas that trace to certain American Quarter Horse bloodlines be tested for HYPP, and owners have the option to choose to place HYPP testing results on registration papers.