Megestrol is a synthetic progestin, a hormone used to postpone estrus (heat cycle) and to relieve the effects of false pregnancy. It can also be used to treat benign prostatic hypertrophy in male dogs and to treat skin and behavior conditions in cats. This long-acting medication lasts for at least 4 – 6 weeks and may last longer in pets with kidney or liver disease. Available in a liquid suspension form for easy administration.