Land: Sør-Afrika
Språk: engelsk
Kilde: South African Health Products Regulatory Authority (SAHPRA)
Bm_squib
PRONESTYL CAPSULES PRONESTYL INJECTION SCHEDULING STATUS S4 PROPRIETARY NAME (and dosage form) PRONESTYL CAPSULES PRONESTYL INJECTION COMPOSITION PRONESTYL CAPSULES: Each capsule contains 250 mg procainamide hydrochloride. PRONESTYL INJECTION: Procainamide hydrochloride 100 mg/mL with benzyl alcohol 0,9% m/v and sodium bisulphite 0,09 % m/v as preservatives. PHARMACOLOGICAL CLASSIFICATION Category A 6.2 Cardiac Depressants. PHARMACOLOGICAL ACTION Procainamide depresses the excitability of cardiac muscle to electrical stimulation and slows conduction in the atrium, the bundle of His, and the ventricle. The refractory period of the atrium is considerably more prolonged than that of the ventricle. Contractility of the heart is usually not affected, nor is cardiac output decreased to any extent unless myocardial damage exists. In the absence of any arrhythmia, the heart rate may occasionally be accelerated by conventional doses, suggesting that the drug possesses anticholinergic properties. Larger doses can induce atrioventricular block and ventricular extrasystoles which may proceed to ventricular fibrillation. These effects on the myocardium are reflected in the electrocardiogram; a widening of the QRS complex occurs most consistently; less regularly the P-R and Q-T intervals are prolonged, and the QRS and T waves show some decrease in voltage. The action of procainamide begins almost immediately after intramuscular or intravenous administration. Plasma levels after intramuscular injection are at their peak in 15 to 60 minutes. Following oral administration, plasma levels of the drug are comparable to those obtained parenterally, and are maximal within an hour; therapeutic levels are usually attained in half that time. Therapeutic plasma levels have been reported to be 3 to 10 µg/mL, wi read_full_document