Why is nitrofurantoin considered inappropriate for use in older adults?

• A. It has a favorable safety profile in all older adults
• B. It is the preferred drug for long-term urinary suppression
• C. It can cause pulmonary toxicity, hepatotoxicity, and peripheral neuropathy, especially with long-term use
• D. It has no significant side effects in older adults

Answer: (C)

Nitrofurantoin is flagged for older adults because its serious toxicities become more likely with longer exposure. In this population, extended or repeated use can lead to pulmonary toxicity (ranging from acute hypersensitivity-like reactions to chronic interstitial lung disease), hepatotoxicity, and peripheral neuropathy. These adverse effects can be severe and sometimes irreversible, which is why the Beers Criteria cautions against using nitrofurantoin for long-term urinary suppression or chronic prophylaxis in older adults. Short courses for uncomplicated lower urinary tract infections may be acceptable in patients with normal renal function, but the risk of these toxicities in older adults—especially with prolonged use—drives the recommendation to avoid it in long-term scenarios. The other statements claim universal safety, preference for long-term suppression, or no significant side effects, which do not fit because nitrofurantoin does carry meaningful, dose- and duration-dependent toxicity in this group.