Objective
:
The purpose of the study was to estimate the pharmacokinetic parameters and calculate the prec
ision (%RMSE) of the predicted l
ithium
concentration equation.
Method
s
:
This research was studied from blood Lithium levels of Children who had visited Yuwaprasa
rt Waithayopathum Child Psychia
tric
Hospital from 31 December 2009
-1 January 2011 The accuracy and precision of the equation were evaluated by the mathematical principle. The
assist package software (WIN
-NONLIN) was used to create pharmacokinetic parameters.
Result
s
:
Twenty
-nine patien
ts were recruited. The characteristics (mean
+SD) presented as the followin
g;
age = 15.79
+2.6
4 y
, weight = 69.75+22.28
kg and the daily dose = 858.62+
274.53 mg. The trough Lithium concentrations (mean
+SD) = 0.56+
19 mg/l
. The kinetic parameter
(Mean
+SD)
pres
ented as the followin
g;
t
1/2
Conclusio
n
:
In conclusion, the modified Yukawa equation may
be used for the prediction of l
ithium concentration with 6.39% RMSE.
=7.23
+3.38 hr., ke =0.12
+0.07 hr
-1, Vd = 48.83
+15.60 L, AUC0
-12 =11.01
+5.61 mg x hr
/l. The population
pharmacokinetic parameter
s;
ke, and AUC (0
-
∞) = 0.151 hr
-1 and 169.81, mg x hr./l
respectively. The mod
ified equation from
Yukawa for l
ithium
cleara
nce calculation and prediction l
ithium concentrations were CL (mL/min) = [36.5+(0.242x
BW (kg)
-7.79]/Scr (mg/dL) and l
ithium
concentration (mg
/l) = 4 x Dose (mg)
/CL (mL/min)x73.89, respectively with 6.39 %RMSE (test for 20 patients
data).