OBJECT DRUGS

CYP1A2 Substrates:

• Anagrelide (Agrylin)
• Asenapine (Saphris)
• Clozapine (Clozaril, etc.)
• Duloxetine (Cymbalta)
• Flutamide (Eulexin)
• Frovatriptan (Frova)
• Loxapine (Loxitane)
• Olanzapine (Zyprexa, etc.)
• Ondansetron (Zofran)
• Ramelteon (Rozerem)
• Riluzole (Rilutek)
• Ropinirole (Requip, etc.)
• Tacrine (Cognex)
• Theophylline
• Tizanidine (Zanaflex)
• Zolmitriptan (Zolmig, etc.)

PRECIPITANT DRUGS

• Smoking

Comment:

Smoking tobacco induces the activity of the enzyme CYP1A2. This induction is caused by polycyclic aromatic hydrocarbons found in tobacco smoke. The induction is related to the amount of tobacco used and can range from a minimal increase to over 5-fold increase. Induction can occur with as few as 10 cigarettes daily and in those exposed to second hand smoke.

Class 3: Assess Risk & Take Action if Necessary

• Consider Alternative: Alternatives for the CYP1A2 substrate could be considered for smokers.
• Monitor: Monitor CYP1A2 substrates for reduced activity in patients currently smoking. Following smoking cessation, the clearance of CYP1A2 substrates will slowly increase and side effects may appear. Adjust doses as necessary.