Removing an adrenal tumor does not stop the course of the disease. Post surgical followup is essential. Aggresive behavior, sometimes accompanied by inappropriate mouunting (as if the ferret were not neutered) is caused by an abnormally high level of testosterone, a hormone, as a result of damaged adrenal function. The same symptoms are evident in female ferrets, caused by increased levels of estrogen and evidenced by an enlarged vulva in the spayed female. These symptoms , exclusive of hair loss, can be controlled with a 1 mg (1 drop, essentially) of a drug called Megace (megesterone acetate) given no more often than once every 4 days until the symptoms subside. In males this may have to be repeated periodically according to symptoms. In females, one treatment may be all that is required. A reduction in testosterone in males can cause lethargy and therefore must be given very carefully and not any more often than absolutely needed, and it must be given for the life of the ferret. If hair loss returns, we have a separete and much different protocol. Megace can be obtained through your veterinarian. Our 1-year shelter adrenal treatment study is now being expanded nationwide through other shelters. Carolyn Kinsey, Ferret Rescue of the Western States, Colorado Springs, Colorado [Posted in FML issue 3314]