Answer
Combining cinnarizine + dimenhydrinate with medicines that prolong the ECG QT interval, such as Class Ia or Class III anti-arrhythmics, should be avoided.
Sources for this answer
- Cinnarizine/Dimenhydrinate 20 mg/40 mg tabletsBrown & Burk UK Ltd · emc · SmPC §4.5 Interaction with other medicinal products · Version 1Document updated
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