治療心律不整 Ventricular and superventricular arrhythmias.

Class Ic Antiarrhythmic Agent
Propafenone is a sodium channel blocker that slows predominantly atrial and ventricular conduction velocities without appreciably prolonging repolarization. It is therefore classified as a class Ic antiarryhthmic, similar to flecanide.

Absorption:
1. Well absorbed
2. Time to peak, serum: 3-8 hours
Distribution:
1. Vd: Adults: 252 L
2. Protein binding: 95% to alpha1-acid glycoprotein
Metabolism:
1. Hepatic via CYP2D6, CYP3A4 and CYP1A2 to two active metabolites (5-hydroxypropafenone and N-depropylpropafenone) then ultimately to glucuronide or sulfate conjugates.
2. Two genetically determined metabolism groups exist (extensive and poor metabolizers).
Excretion:
Urine (<1% unchanged; remainder as glucuronide or sulfate conjugates); feces
Half-life elimination:
Extensive metabolizers: 2-10 hours; Poor metabolizers: 10-32 hours

C

Enters breast milk; use caution

Most frequently occur in the CNS, cardiovascular, and GI system: dizziness, anxiety, dyspnea, upper respiratory infection, fatigue , chest pain Edema, palpitations, constipation, nausea, taste sense altered, vomiting.

150 mg Q8H, increase dosage at 3-4-day intervals to 225-300 mg Q8H if need.

1. Not provided in the manufacturer's labeling; however, 50% of propafenone metabolites (some active) are excreted in the urine
2. Hemodialysis/CVVH: Minimally dialyzable; supplemental dose not necessary

Mild to moderate impairment dosing recommendations:
Initial 150 mg once daily; if necessary, may increase dosage by 150 mg/day in divided doses (eg, twice daily, three times daily) at a minimum of 4-day intervals up to maximum of 300 mg every 12 hours