Psychotherapeutic agents in older adults. Commonly prescribed and over-the-counter remedies: causes of confusion.

Acute confusion is associated with significant morbidity and mortality among older persons. Among the common causes of confusion, medications are at the top of the list. Since virtually any drug can cause confusion, it is helpful for the clinician to know which patients are at risk and which medications are risky. At particular risk are patients with dementia and patients whose pharmacokinetics or pharmacodynamics have been impaired by the aging process or diseases. The list of medications that can cause confusion is a long one, yet it can be remembered by the mnemonic ACUTE CHANGE IN MS (mental status). In addition to recognizing the offending agent, it is prudent for clinicians to prevent the chance of drug-induced confusion. One of the safest ways to do this is to avoid too many medications since the risk of adverse drug events rises exponentially with the number of medications prescribed.