Quinidine and Other Type Ia Antiarrhythmic Drugs
Quinidine, procainamide (Pronestyl), and disopyramide (Norpace) are type Ia antiarrhythmic agents. Quinidine and procainamide are used commonly for suppression of supraventricular and ventricular arrhythmias. Disopyramide is used for ventricular arrhythmias. All three agents have a low toxic-to-therapeutic ratio and may produce fatal intoxication (Table II–51). See the description of other antiarrhythmic agents in Amphetamines.
Table II-51 Quinidine and Type Ia Antiarrhythmic Drugs
Table II-51 Quinidine and Type Ia Antiarrhythmic Drugs
Drug | Serum Half-life (h) | Usual Adult Daily Dose (mg) | Therapeutic Serum Levels (mg/L) | Major Toxicitya |
|---|---|---|---|---|
Disopyramide | 4–10 | 400–800 | 2–4 | B, V, H |
Procainamide | 4 | 1000–4000 | 4–10 | B, V, H |
NAPAb | 5–7 | N/A | 15–25 |
