The prevalence of orthostatic hypotension (OH) in hypertensive patients ranges from 3 to 26%. Drugs are a common cause of non-neurogenic OH. In the present study, we retrospectively evaluated the medical records of 9242 patients with essential hypertension referred to our Hypertension Unit. We analysed data on supine and standing blood pressure values, age, sex, severity of hypertension and therapeutic associations of drugs, commonly used in the treatment of hypertension. OH was present in 957 patients (10.4%). Drug combinations including α-blockers, centrally acting drugs, non-dihydropyridine calcium-channel blockers and diuretics were associated with OH. These pharmacological associations must be administered with caution, especially in hypertensive patients at high risk of OH (elderly or with severe and uncontrolled hypertension). Angiotensin-receptor blocker (ARB) seems to be not related with OH and may have a potential protective effect on the development of OH.