Theophylline should be administered on which basis?

• A. With meals
• B. With antacids
• C. On an empty stomach
• D. At bedtime

Answer: (C)

The main idea is that theophylline absorption and blood levels are highly sensitive to how it is taken, and this drug has a narrow therapeutic window. To get a predictable, steady absorption, it is given on an empty stomach. Food can slow or alter the rate and extent of absorption, leading to fluctuating plasma levels that make it hard to stay within the safe and effective range. Antacids and changes in stomach pH can also modify absorption, further increasing variability. Taking it with meals would not improve consistency, and taking it at bedtime doesn’t address the absorption differences caused by food. By administering on an empty stomach, clinicians can more reliably achieve the desired plasma concentration and minimize toxicity risk, especially since theophylline dosing also depends on individual factors like smoking status and liver function, with serum levels routinely monitored.