This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Asthma, Subject name: Pharmacology
Theophylline metabolism interaction with ciprofloxacin 
Select and explain. 
A. Increases theophylline metabolism, B. Decreases theophylline metabolism, C. Increases ciproflexacin metabolism, D. Decreases ciprofloxacin metabolism
B: Decreases theophylline metabolism
Answer: B: Decreases theophylline metabolism 
Explanation: (Decreases theophylline metabolism) (221-KDT 6th)* Ciprofloxacin and ofloxacin can Increases the serum levels of theophylline by inhibiting its metabolism Agents which induce theophylline metabolism decreases its plasma level Drug which inhibit theophylline metabolism and Increases its plasma levels* Smoking* Phenytoin* RifampicinPhenobarbitoneCharcoalBroiled meat meal* Erythromycin* Ciprofloxacin* CimetidineOralcontraceptiveAllopurinol Theophylline enhances the effects of - Furosemide, sympathomimetics, digitalis, oral anticoagulants, hypoglycemics Theophylline decreases the effects of - Phenytoin, lithium