Field application of a colorimetric method of assaying chloroquine and desethylchloroquine in urine

These tests are, however, less specific and Plasmodiumfalciparum in new areas and assessment sensitive than analysis of plasma or whole blood and of changes in areas with known chloroquine resist- show greater individual variation owing to differ- ance can be aided by measuring the levels of the drug ences in the rate of drug absorption, tissue distri- in the body fluids of individuals or populati [...] None the less, the The sensitivity and predictive value for a cut-off of ability to rapidly estimate chloroquine+desethyl- A 1 mg/l in urine for the adjusted level of chloro- chloroquine levels outweighs the disadvantages ofthe quine+desethylchloroquine and of <100 jsg/l for lower sensitivity and greater biological variation in the chloroquine in whole blood were 84% and 89%, urine measurements ma [...] The use of a hand-held, battery-operated Determination of chloroquine+desethylchloro- filter photometer permitted precise quantification of quine in urine showed an intra-test error of 0.04 the results; however, the test could also be performed of transmittance units for 20 repeated photometric quantitatively by visual comparison of photometer measurements. [...] DISCUSSION In the field study ofthe described modification ofthe Haskins test, we found a highly significant correlation between the level of chloroquine+desethylchloro- quine in urine and that of chloroquine in whole blood for 28 days after treatment with the drug. [...] P. falciparum to chloroquine the test could be used to Determination of the concentration of chloro- verify recent ingestion of the drug and to help in quine+desethylchloroquine in urine can assist in estimating the amount taken.