[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Antiarrhythmics](https://durgical.com/en/pharmacology/classes/antiarrhythmics/) › Disopyramide

# Disopyramide

## Antiarrhythmics?

Antiarrhythmics

An oral class IA antiarrhythmic with strong anticholinergic and negative inotropic effects. It can worsen heart failure and cause urinary retention.

Updated Nov 1, 2026

## Quick facts

**Group**
[Antiarrhythmics](https://durgical.com/en/pharmacology/classes/antiarrhythmics/)

**Target**
Cardiac sodium channel Nav1.5 (and muscarinic receptors)

**Key effects**
Dry mouth · Urinary hesitancy and constipation

**Monitor**
ECG · Signs of heart failure · Kidney function

**ATC**
C01BA03

No doses: the clinician sets them by the current guideline.

On this page

- The basics Mechanism of action
- Indications
- Adverse effects
- Pharmacokinetics
- Memory aid

- Safety Contraindications
- Key interactions
- What is monitored
- Administration and safety
- Pregnancy and breastfeeding
- Nursing care

- Study Test yourself

- Connections Connections

## Mechanism of action

Disopyramide blocks cardiac sodium channels and lengthens repolarisation (class IA: wider QRS and longer QT). It depresses contractility more than other class I drugs and has marked anticholinergic activity, which explains dry mouth, constipation and urinary retention.

- Disopyramide blocks sodium channels and lengthens repolarisation
- Contractility falls (negative inotropic effect)
- Muscarinic block causes anticholinergic effects

## Indications

- Documented life-threatening ventricular arrhythmias such as sustained ventricular tachycardia [Ventricular tachycardia →](https://durgical.com/en/conditions/ventricular-tachycardia/)

## Adverse effects

### Common

- Dry mouth
- Urinary hesitancy and constipation
- Blurred vision and dry eyes

### Serious (rare, important)

- New or worse heart failure and severe hypotension
- QT prolongation and worse ventricular arrhythmias
- Urinary retention
- Hypoglycaemia (rare)

## Contraindications

- Cardiogenic shock
- Second- or third-degree AV block without a pacemaker
- Congenital long QT
- Hypersensitivity to disopyramide
- Glaucoma, urinary retention, prostatic hypertrophy or myasthenia gravis, unless managed (anticholinergic)

## Key interactions

**Other class IA or IC antiarrhythmics and propranolol**
Additive negative inotropy and conduction slowing

**Erythromycin and other CYP3A4 inhibitors**
Higher disopyramide levels, QT prolongation

## What is monitored

- ECG: QRS and QT
- Signs of heart failure and blood pressure
- Kidney function
- Blood glucose in at-risk patients

## Administration and safety

- Immediate-release and controlled-release capsules are different products: the product is checked.
- In cardiomyopathy or possible decompensation, it is started cautiously without a loading phase.

## Pregnancy and breastfeeding

It has been found in fetal blood and can stimulate uterine contractions, so it is used in pregnancy only if clearly needed.

## Nursing care

- Ask about difficulty passing urine, constipation and dry mouth, especially in older men.
- Watch for breathlessness, swelling and low blood pressure.
- Teach signs of low blood sugar.

## Pharmacokinetics

**Metabolism**
Liver, by CYP3A4

**Elimination**
More than half unchanged in urine, so the dose is reduced in kidney impairment

## Memory aid

DISOpyramide DISObeys the bladder and the heart: can't pee, can't pump (anticholinergic plus negative inotrope).

## Test yourself

Think of the answer, then tap the question to see it.

## Which two properties set disopyramide apart from other class IA drugs?

Strong negative inotropic effect and marked anticholinergic activity.

## Why is disopyramide avoided in glaucoma and prostatic hypertrophy?

Its anticholinergic effect can raise eye pressure and cause urinary retention.

## Why is the disopyramide dose reduced in kidney failure?

More than half is excreted unchanged in the urine.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/disopyramide/)

[More Pharmacology questions →](https://durgical.com/en/practice/?f=pharmacology)

## Connections

## Related drugs 3

- [Quinidine](https://durgical.com/en/pharmacology/quinidine/)
- [Procainamide](https://durgical.com/en/pharmacology/procainamide/)
- [Atropine](https://durgical.com/en/pharmacology/atropine/)

## Related conditions 1

- [Ventricular tachycardia](https://durgical.com/en/conditions/ventricular-tachycardia/)

[← Back to the class: Antiarrhythmics](https://durgical.com/en/pharmacology/classes/antiarrhythmics/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: [DailyMed - DISOPYRAMIDE PHOSPHATE capsule, gelatin coated](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=31e79459-107f-4d69-a163-90014f1c4772) (DailyMed (U.S. National Library of Medicine), 2026); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=C01BA03) (WHO Collaborating Centre for Drug Statistics Methodology, 2026).

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Representative model, for educational purposes only.

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Source: https://durgical.com/en/pharmacology/disopyramide/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/disopyramide/