Taking varenicline with other medicines and herbal supplements

Varenicline does not usually have an effect on any other medicines. Check with your doctor before using varenicline with other stop smoking treatments.

However, when you stop smoking, with or without varenicline, your doctor may need to change your dose of medicines such as:

• theophylline or aminophylline, medicines for breathing problems
• erlotinib, a medicine to treat cancer
• riociguat, a medicine to treat high blood pressure in the lungs (pulmonary arterial hypertension)
• warfarin, a medicine to reduce blood clotting
• insulin, to treat diabetes
• olanzapine and clozapine, used to treat psychosis