Phenytoin dose adjustment in epileptic patients.

摘要: Abstract 1 A preliminary survey showed that many outpatients with partially controlled epilepsy had serum concentrations of phenytoin below the recommended therapeutic range (10-20 μg/ml). tolerance test was devised intention predicting a more adequate daily dose for such patient. 2 Fifteen patients were each given an oral 600 mg sodium and concentration measured at intervals over 48 h; rose during first 4 h decayed between 12-48 as almost linear function time. 3 The concentration/time curves fitted by interative computer program based on Michaelis-Menten equation. mean saturated rate elimination 435 mg/day (Km) corresponding 50% saturation 3.8 μg/ml. calculated required steady state 10-20 μg/ml 345-400 mg/day. 4 principle used to predict in individual receiving doses adjusted steps 100 mg. tended be either too low or high. steep relationship indicates when reaches 5-10 it is then appropriate adjust small about 25