PO: Propafenone therapy should be initiated in a hospital with facilities for cardiac rhythm monitoring. Most serious proarrhythmic effects are seen in the first 2 wk of therapy.
» Swallow sustained-release capsules whole; do not open, crush or chew.
» Previous antiarrhythmic therapy should be withdrawn 25 half-lives before starting propafenone.
» Dose adjustments should be at least 34 days apart because of the long half-life of propafenone.
» Correct pre-existing hypokalemia or hyperkalemia prior to instituting therapy.