Dantrium (Dantrolene Capsules) and Disopyramide Phosphate

• Generic Name: dantrolene
• Dosage Forms: capsule
• Other Brand Names: Dantrium, Dantrium Intravenous, Revonto, Ryanodex

• It is used to relax muscles.
• It is used to treat or prevent a health problem called malignant hyperthermia.

• Generic Name: disopyramide
• Dosage Forms: n.a.
• Other Brand Names: Norpace, Norpace CR

Precise role in antiarrhythmic therapy has not been established. Some experts recommend that disopyramide be reserved for use as an alternative drug when lidocaine, quinidine, or procainamide is ineffective or adverse effects of these drugs are intolerable.

Limited information is available on combination therapy with other antiarrhythmic drugs such as lidocaine, quinidine, or procainamide to treat or prevent serious, refractory arrhythmias.

Suppression and prevention of recurrent life-threatening ventricular arrhythmias (e.g., sustained VT). (See Boxed Warning.)

Because of disopyramide’s arrhythmogenic potential and lack of evidence for improved survival for class I antiarrhythmic agents, use for less severe arrhythmias is not recommended.

Avoid treatment of asymptomatic VPCs.

Has been used to convert atrial fibrillation, atrial flutter, and paroxysmal atrial tachycardia to normal sinus rhythm. However, other antiarrhythmic drugs (e.g., dofetilide, flecainide, ibutilide, propafenone, amiodarone) are preferred.