This patient, an 80-year-old woman, presented with severe dizziness and blackouts. She was taking medications for hypertension and angina that can cause postural hypotension, including hydrochlorothiazide, isosorbide mononitrate, and nifedipine. On examination, her blood pressure was significantly lower when standing than supine. The underlying problem is symptomatic postural hypotension caused by the combined effects of the antihypertensive medications, which is made worse by age-related physiological changes. Drugs that reduce blood pressure or impair autonomic responses in the elderly can cause postural hypotension, so the smallest effective doses should be used.