Objectionable urine spraying and urine marking in cats: evaluation of progestin treatment in gonadectomized males and females.

The increasing use of long-acting progestins to treat objectionable urine spraying and urine marking in gonadectomized cats prompted a survey of the comparative effectiveness of the injectable medroxyprogesterone acetate (MPA) and the orally administered megestrol acetate (MA). Both drugs were successful, overall, in about 1/3 of the patients. However, the proportion with favorable response was higher for males (48%) than for females (13%) and was higher for cats from single-cat homes (50%) than for cats from multi-cat homes (18%). Because of the reportedly higher frequency of depression and increased appetite following MA treatment, when compared with MPA treatment, it is recommended that MPA be used initially for routine treatment of these behavioral problems. The survey revealed that if MPA proves ineffective, subsequent treatment with MA can be expected to yield favorable results in some of these patients.