A client on chronic theophylline is given a new prescription… | MyMerci
Medical EmergenciesPA
Question
A client on chronic theophylline is given a new prescription for ciprofloxacin to treat a UTI. Which is the nurse's priority action?
1Take ciprofloxacin with an antacid for better absorption
2Administer both medications as ordered
3Notify the provider — ciprofloxacin is a strong CYP1A2 inhibitor and increases theophylline levels; an alternative antibiotic or theophylline dose adjustment is needed✓ Correct answer
4Stop theophylline permanently
Explanation
Correct (2): Ciprofloxacin is a potent CYP1A2 inhibitor that raises theophylline levels into the toxic range, causing seizures and arrhythmias. Use an alternative non-quinolone (or non-1A2-inhibiting) antibiotic, or reduce theophylline dose with close level monitoring. (1) Dangerous. (3) Antacids reduce ciprofloxacin absorption. (4) Theophylline is not permanently stopped without indication.
In-depth explanation
Memory Tip Theophylline + Ciprofloxacin = level UP. Other 1A2 inhibitors: erythromycin, fluvoxamine, oral contraceptives (modest). Always cross-check level when adding interacting drugs.
Clinical scenario
Scenario 60-year-old female on stable theophylline 200 mg BID for asthma. ED provider prescribes ciprofloxacin 500 mg PO BID × 7 days for a UTI.