In order to treat postprandial hypotension (PPH), we orally administered a combination of denopamine (10 mg, a selective beta 1-adrenergic agonist) and midodrine-HCl (4 mg, a selective alpha 1-adrenergic agonist) to eight patients with autonomic failure (AF) prior to and after eating. When the patients were given 75 g glucose with 225 ml water without drugs, blood pressure fell subsequently, cardiac output (CO) was unchanged, and vascular resistance of the lower legs (LVR) decreased. However, concomitant administration of denopamine and midodrine-HCl prevented PPH and increased CO and LVR. The portal blood flow was not indifferent to the drugs. A marked increase in heart rate after drug administration was seen in some patients with AF, which reflects the supersensitivity to denopamine. Combined oral administration of denopamine and midodrine-HCl is a safe and useful therapy for PPH in patients with AF.