A method is described for the prophylaxis or treatment of hypertension in a cat in need of such treatment. The method includes administration of a therapeutically effective amount of angiotensin II receptor 1 (AT-1) antagonist (sartan) to the cat, where the therapeutically effective amount of the sartan is administered in a daily dosage amount that is varied over a treatment period, the daily dosage amount of the sartan for a first period of time during the treatment period is 1.0 to 5.0 mg/kg of body weight, and the daily dosage amount of the sartan is decreased for a second period of time subsequent the first period of time during the treatment period.