Antidysrhythmic drugs
Antidysrhythmic drugs

(none licensed for use in horses)

Quinidine gluconate: Soluble preparation different from quinidine sulphate, not available in the UK at present. If available can be used to treat supraventricular and ventricular arrhythmias at 0.5-1.0 mg/kg IV every 10 minutes, or as an infusion to a maximum dose of 4mg/kg.

Quinidine sulphate:

For AF: 10g/500kg every 2 hours by stomach tube up to total dose of 60-80 g (guideline).

Then every 6 hours until conversion. Aim to keep in therapeutic range of 2.0~.5 mg/l.

For VPCs: may have to be used for protracted treatment at 10 mg/kg by stomach tube

every 6 hours if quinidine gluconate is not available

Lignocaine: IV 0.5 mg/kg boluses every 5 minutes, or as an infusion. Do not exceed total dose of 2.0-4.0 mg/kg. Ataxia/convulsions can occur (uncommon). These can be treated with diazepam at a dose of 0.1-0.2 mg/kg IV if necessary.

Pro panalol: 0.05-0. lSmg/kg twice daily IV or 0.3-0.7 mg/kg PO. Little experience with this drug is reported.

Digoxin: (See positive inotropes.)

Atropine: Use for bradycardias which are sufficiently severe to result in prolonged clinical

signs. Dose 0.01-0.015 mg/kg IV.

Glycopyrolcte:0.005-0.01 mg/kg IV used as an alternative to atropine.