Altrenogest is effective in normally cycling mares for minimizing the necessity for estrus detection, for the synchronization of estrus, and permitting scheduled breeding. Estrus will begin 2-5 days after treatment is completed and most mares ovulate for between 8-15 days after withdrawal. Altrenogest is also effective in suppressing estrus expression in show mares or mares to be raced. Altrenogest has been demonstrated to maintain pregnancy in oophorectomized mares and may be of benefit in mares that abort due to subtherapeutic progestin levels.

FOR RX ONLY: A valid prescription from a licensed veterinarian is required for dispensing this medication.