THE EFFECT OF VITAMIN C ON PHARMACOKINETIC PARAMETERS OF CHLOROQUINE IN HEALTHY HUMAN VOLUNTEERS

THE EFFECT OF VITAMIN C ON PHARMACOKINETIC PARAMETERS OF CHLOROQUINE IN HEALTHY HUMAN VOLUNTEERS

Abstract:

This study was undertaken to compare the effect of vitamin C on the pharmacokinetics of chloroquine using human volunteers. Quality control studies for both chloroquine and vitamin C; identification test, assay, weight variation, friability, disintegration time and dissolution rate were carried out according to BP 2009. Jayanathi et al., 1994 method was adopted and validated based on ICH guideline for this study. Calibration curve was constructed within the range of 2 – 10 μg/ml and validated. The adopted method was then employed in determining the effect of vitamin C on the pharmacokinetics parameters (Cmax, Tmax, Ka, Ke, t1/2a, t1/2e, Cl, Vd, lag time and AUC) of chloroquine using human volunteers of 30 years and above and the study was divided into three phases with a washout period of three weeks. Both chloroquine and vitamin C used for this study were found to have the labeled active ingredient. They all passed the assay test as they were within the acceptable limits 95 – 105 %. Weight variation was conducted for both chloroquine and vitamin C and they all passed as their percentage mean deviation was less than 5 %. Similarly, both drugs passed the friability test which was less than 1%. Disintegration tests for both drugs reveals that they disintegrate in less 5 mins and also both chloroquine and vitamin C passed the dissolution rate as more than 70 % of the active ingredient was released in 30 mins. The percentage recovery of the method was within the accepted range of 98 – 102 %. Calibration curve was linear within the range of 2 – 10 μg/ml as the correlation coefficient was 0.9905. The regression equation was y= 0.001x + 0.120. When chloroquine was administered alone no significant difference (p<0.05) at lower values was observed, however, on co-administration of chloroquine and vitamin C no significant difference (p<0.05) at lower values was also observed, except for clearance (Cl) which was statistically significant (p<0.05) at lower values. On the other hand, when an hour delayed administration of chloroquine and vitamin C no significant difference (p<0.05) was observed, except for clearance (Cl) which was also statistically significant (p<0.05) at lower values. This finding indicates that vitamin C may influence the pharmacokinetics of chloroquine when co-administered together depending on the time of administration of the two drugs

THE EFFECT OF VITAMIN C ON PHARMACOKINETIC PARAMETERS OF CHLOROQUINE IN HEALTHY HUMAN VOLUNTEERS