A medical student self-medicates with doxycycline for acne. He swallows the capsule at bedtime with only a sip of water and lies down immediately. Three days later he presents with retrosternal burning pain worse on swallowing. The most likely diagnosis and correct preventive advice are:

• A Reflux esophagitis; take the drug with antacids at bedtime
• B Infective esophagitis; the capsule should be opened and mixed with food
• C Pill-induced esophagitis; swallow tablets with a full glass of water while sitting or standing upright ✓
• D Eosinophilic esophagitis; the drug should be taken on an empty stomach

Explanation

Tetracyclines, especially doxycycline capsules, are a leading cause of pill-induced esophagitis. Retention of the capsule in the distal esophagus during sleep causes direct mucosal injury, producing odynophagia and retrosternal pain. Prevention is taking the drug with plenty of water and remaining upright for some time. Antacids are counterproductive because polyvalent cations chelate tetracyclines and reduce absorption, and opening the capsule worsens local irritation.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

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Written and medically reviewed by the StethoPrep medical team.