Gastrointestinal drug interactions affecting the elderly.

With the burgeoning elderly population in the United States, drug interactions are an increasing concern because of altered drug metabolism associated with age and polypharmacy. This article describes interactions between drugs used in common gastrointestinal diseases, including acid peptic disease, diarrhea, constipation, endoscopic procedural sedation, and inflammatory bowel disease, and those used to treat 5 common geriatric primary care diseases: hypertension, diabetes, hyperlipidemia, arthritis, and psychiatric illnesses.