You should tell your doctor if you are using medicines containing any of the following active substances: • atorvastatin, used to reduce cholesterol levels • calcium channel blockers (e.g. amlodipine), used to treat raised blood pressure • theophylline, used to treat asthma • warfarin, used as a blood thinning agent • phenytoin, used to treat convulsions • ciclosporin, used to suppress your immune system during organ transplants • benzodiazepines (e.g. temazepam), used to relieve anxiety