More Info on Interactions With Calan SR
Calan SR can interact with various chemotherapy medications, causing a variety of effects. Always make sure to tell all of your healthcare providers about any medications you are taking.
Cimetidine may increase the level of Calan SR in your blood, increasing your risk of Calan SR side effects (although drug interaction studies have shown mixed results). Your healthcare provider may need to adjust your Calan SR dose or may suggest an alternative to cimetidine.
There have reports of a dangerously slow heart rate in people who combined clonidine and verapamil (the active ingredient in Calan SR). Some cases were serious enough to require hospitalization and even the insertion of a pacemaker. Check with your healthcare provider before taking these medications together.
Cyclosporine (Gengraf, Neoral, Sandimmune)
Calan SR may increase the level of cyclosporine in your blood, increasing your risk of side effects. Your healthcare provider should closely monitor your cyclosporine levels and may need to adjust your dosage.
CYP 3A4 Inducers
Calan SR is broken down (metabolized) by certain liver enzymes known as CYP 3A4 enzymes. Other medications (known as CYP 3A4 inducers) that increase the activity of these enzymes can decrease the level of Calan SR in the blood, making Calan SR less effective. Check with your healthcare provider before taking Calan SR with any of these medications. If you have already been taking such medications with Calan SR, check with your healthcare provider before stopping them.