Polycyclic aromatic hydrocarbons found in tobacco smoke are associated with clinically significant drug interactions related to what hepatic enzyme effect?
CYP1A2 enzyme induction. This increases theophylline clearance up to 100% leading to potential toxicity after smoking cessation. Some authors recommend decreasing the dose of CYP1A2 substrates 10% per day until the fourth day after smoking cessation due to rapid reduction of enzyme activity.
Contributor: Rachel Schult, PharmD, DABAT, University of Rochester Medical Center
Kroon LA. Drug interactions with smoking. Am J Health Syst Pharm 2007;64(18):1917-21. doi: 10.2146/ajhp060414.