24시간 혈청농도를 이용한 lithium 치료량 예측법의 평가

Evaluation of the 24-Hour Serum L ith ium Level as a Prognosticator of Dosage Requirements

Lithium salt is a primary therapeutic and prophylactic agent for manic depressive disorder. But, safety range of the lithium salt is relatively narrow and the dosages to main tain optimum the rapeutic serum level vary among individuals. By these reasons, it has been suggested that the application of lithium should start from low dosage and increase grad ually by close observations of therapeutic effects ancl side reactions. This method, however, takes relatively longer period to reach the effective serum lithium level and manifests possible lithium to xicity . In 1973, Cooper and his colleagues reported the 24-hour serum lithium level as a prog nosticator of dosage requirements for rapid and safe use of lithium salt, The authors attempted to evaluate the accuracy of this method as aprog nosticator of dosage requirements. Subjects of the study was 25 cases of manic depressive disorder. According to Cooper’s me thod , 600mg of lithium carbonate was administered orally to the patients and blood was sampled 24-hours later. The required dosages of lithium carbonate to reach therapeutic serum level (0. 6〜 1. 2m E q /L ) had been given orally and serum lithium levels were checked on the 7th and 14th days respectively after initial medication. The results are as follows： 1. Sensitivity of Cooper’s method could be proved to be 0.80〜0.84. If the range of optimum serum lithium level is assumed to be 0 .6 ~1 . 5 mEq /L ,the sensitivity would be 0.96〜 1.00. 2. After the Cooper’s method, the 7th day serum checking seems to be sufficient to confirm th erapeutic serum level. From the above results, the Cooper’s method was proved to be useful prognosticator of dosage requirement for rapid and safe lithium treatment.