Studies of the biological availability of phenytoin preparations (Polfa) and micronized phenytoin in patients with cardiac rhythm disorders
Wierzchowiecki, M.; Swiderczuk, A.; Dyderski, S.; Masiakowski, J.; Jazienicki, B.
Kardiologia Polska 30(9): 577-582
1987
ISSN/ISBN: 0022-9032 PMID: 2447321 Document Number: 303234
5 males aged 20-43 with ventricular arrhythmias underwent the study. Phenytoinum (Polfa) single daily oral dose of 5 mg, 10 and 15 mgs/kg b.w. or divided oral dose of 15 mg/kg b.w. was randomly administrated as well as 10 mg/kg micronized phenytoin. Serum drug concentrations were determined from 30 minutes to 120 hours after drug administration using a gas chromatography method. It was stated, that phenytoin micronization greatly improved drug bioavailability. Phenytoinum (Polfa) bioavailability in comparison with its micronized preparation was 43,8 per cent. Phenytoin bioavailability is dependent on a drug dose and a route of its administration. Its improvement is observed after administration of a drug in divided doses which leads to quick obtainment of therapeutic effect.