Pergolide is a medication that is used to treat Cushing’s disease in horses. The form commonly available to horse owners is compounded (made into solution from a powder). A recent study has shown that temperature and light exposure decrease its stability and efficacy. We now recommend you refrigerate Pergolide and make sure that it is stored in a light protective container. The study showed that if properly stored, Pergolide is stable for up to 60 days. It is ideal to buy a 30 day supply (as opposed to a 60-90 day supply) at a time. If you have any questions or are concerned that your horse may need this medication, please give us a call.