Clarithromycin and Disopyramide interaction
Clarithromycin and Disopyramide: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Clarithromycin label · effective 2026-01-01
…with colchicine; markedly increased transaminases with lomitapide; rhabdomyolysis with simvastatin, lovastatin, and atorvastatin; hypoglycemia and cardiac arrhythmias (e.g., torsades de pointes) with disopyramide; and hypotension and acute kidney injury with calcium channel blockers metabolized by CYP3A4 (e.g., verapamil, amlodipine, diltiazem, nifedipine).
QT Prolongation : Avoid clarithromycin tablets in patients with known QT prolongation or receiving drugs known to prolong the QT interval, ventricular arrhythmia ( torsades de pointes ), hypokalemia/hypomagnesemia, significant bradycardia, or taking Class IA or III antiarrhythmics ( 5.2 )
…Interactions with Clarithromycin Tablets Drugs That Are Affected By Clarithromycin Tablets Drug(s) with Pharmacokinetics Affected by Clarithromycin Tablets Recommendation Comments Antiarrhythmics: Disopyramide Quinidine Dofetilide Amiodarone Sotalol Procainamide Not Recommended Disopyramide, Quinidine: There have been postmarketing reports of torsades de pointes…
There have been postmarketing reports of hypoglycemia with the concomitant administration of clarithromycin and disopyramide.
Therefore, blood glucose levels should be monitored during concomitant administration of clarithromycin and disopyramide.
From the Disopyramide (Norpace) label · effective 2026-08-24
Although specific drug interaction studies have not been done, cases of life-threatening interactions have been reported for disopyramide when given with clarithromycin and erythromycin.
Cases of life-threatening interactions have been reported for disopyramide when given with clarithromycin and erythromycin indicating that coadministration of disopyramide with inhibitors of cytochrome 3A4 could result in potentially fatal interaction.
Although potent inhibitors of cytochrome P450 3A4 (e.g., ketoconazole) have not been studied clinically, in vitro studies have shown that erythromycin and oleandomycin inhibit the metabolism of disopyramide.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.