Ivabradine Diltiazem

CALCIUM CHANNEL BLOCKERS IVABRADINE t levels with diltiazem and verapamil Uncertain Avoid co-administration... 

Ivabradine is metabolised by CYP3A4 and its levels may therefore be increased significantly in the presence of inhibitors of this isoenzyme, such as some azoles, diltiazem, some macrolides, ne-fazodone, protease inhibitors, or verapamil. 

A study found that ketoconazole 200 mg daily or josamycin 1 g twice daily increased ivabradine plasma levels by seven to eightfold. Studies in healthy subjects given diltiazem or verapamil have resulted in an increase in the AUC of ivabradine of two to threefold, and an additional heart rate reduction of 5 bpm. ... 

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