disopyramide at a glance
Medicine class
Class Ia antiarrhythmic with anticholinergic and heart-contractility-reducing effects.
Main role
Control or prevention of specified atrial and ventricular arrhythmias.
Important monitoring
ECG, potassium and blood glucose monitoring may be needed.
What is disopyramide used for?
Selected UK products are licensed to treat or prevent specified cardiac arrhythmias.
Maintaining normal rhythm after electrical or medicine-assisted conversion.
Preventing or treating arrhythmias associated with myocardial infarction.
Treating persistent ventricular or atrial extrasystoles and preventing paroxysmal supraventricular tachycardia.
Treating arrhythmias associated with Wolff–Parkinson–White syndrome.
Suppressing arrhythmias during procedures and controlling arrhythmias associated with cardiac glycosides.
How does disopyramide work?
Disopyramide blocks cardiac sodium channels, reducing abnormal electrical excitability and slowing conduction. It lengthens refractory periods in parts of the heart, helping prevent repeated abnormal impulses. It can also reduce cardiac contractility and has anticholinergic effects.
disopyramide preparations and strengths
Capsule
Route: Oral
Strengths: 100 mg
Modified-release tablet
Route: Oral
Strengths: 250 mg
disopyramide side effects
Common or expected effects
- Dry mouth
- Constipation, nausea, vomiting, abdominal discomfort or diarrhoea
- Blurred or double vision
- Difficulty passing urine
- Dizziness or headache
- Problems with memory, attention or clear thinking, particularly in older people
Get urgent medical advice
- New or worsening palpitations, fainting, marked dizziness or an unusually fast or slow heartbeat
- Breathing or swallowing difficulty, facial or throat swelling, or another severe allergic reaction
- Severe low blood sugar, with sweating, pallor, drowsiness, confusion or unconsciousness
- Inability to pass urine or symptoms of bowel obstruction
- Sudden fever, severe sore throat or mouth ulcers, which may indicate a white-cell disorder
- Yellow skin or eyes
disopyramide in pregnancy
Human pregnancy safety data are limited, and disopyramide can stimulate uterine contractions. It should be considered only when a specialist judges that the expected benefit outweighs potential maternal and fetal risks. Contact the prescribing team promptly if pregnancy occurs.
disopyramide while breastfeeding
Disopyramide and its active metabolite enter breast milk. Published experience is limited and specialist assessment is needed. If breastfeeding continues, the infant may require observation for poor feeding, reduced wet nappies or other anticholinergic effects. Disopyramide may theoretically reduce milk production.
disopyramide interactions
Check all prescribed, over-the-counter and herbal products because some combinations can alter heart rhythm, potassium or disopyramide exposure.
Other antiarrhythmics and QT-prolonging medicines
The combination can worsen rhythm disturbances or increase torsades de pointes risk and is generally contraindicated or avoided.
Macrolide antibiotics and azole antifungals
They may prolong QT and inhibit CYP3A, potentially increasing disopyramide exposure and arrhythmia risk.
Common questions about disopyramide
Answers are fully visible for fast scanning and source review.
What is disopyramide used for?
It treats or prevents selected abnormal heart rhythms and can maintain normal rhythm after cardioversion.
Can disopyramide make an abnormal heartbeat worse?
Yes. It can occasionally cause a new arrhythmia or worsen an existing one. New palpitations, marked dizziness or fainting need urgent assessment.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.