Theophylline – Drug interactions

Certain drugs inhibit theophylline metabolism, thus increasing blood levels and cause toxicity:

• Ciprofloxacin
• Cimetidine
• Erythromycin
• Allopurinol
• Oral contraceptives

Some others increase theophylline metabolism, decreasing blood levels:

• Phenobarbitone
• Phenytoin
• Rifampicin

Smoking and consumption of charcoal boiled meat also increase theophylline metabolism.