Answer
Yes. It can prolong the QT interval and rarely cause serious arrhythmias, particularly when other cardiac risk factors or QT-prolonging medicines are present.
Sources for this answer
- Pentamidine isetionate Tillomed 300 mg powder for solution for injection/infusion — Current selected SmPCemc · Summary of Product Characteristics
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.