Answer
Combining propranolol with verapamil or diltiazem can cause severe hypotension, bradycardia and cardiac failure, particularly with impaired ventricular function or SA/AV conduction abnormalities; neither drug should be administered intravenously within 48 hours of discontinuing the other.
Sources for this answer
- Propranolol Rosemont 50mg/5ml Oral SolutionRosemont Pharmaceuticals Limited · emc · SmPC §4.5 Interaction with other medicinal products · Version 12Document updated
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