The effect of
penicillins (
ampicillin,
carbenicillin,
penicillin G, and
penicilloic acid) and
aminoglycosides (
amikacin,
gentamicin,
streptomycin, and
tobramycin) on the accuracy of
Clinitest, Diastix, and TesTape determinations of
glycosuria was studied. Solutions of each of the drugs were prepared in urine in a range of clinically obtainable
drug concentrations. In addition, urine solutions were prepared that contained the same
drug concentrations and sufficient
glucose to give final concentrations of 0.5, 1, and 2%. All solutions were tested in triplicate using the five-drop
Clinitest method, Diastix, and TesTape. Falsely elevated and falsely decreased
Clinitest readings were obtained with the
penicillins. These readings were influenced by the concentration of the
penicillins and of
glucose. The
aminoglycosides had no effect of
Clinitest determinations. Neither
drug class interfered with Diastix or TesTape readings. The
Clinitest-
penicillin interaction is unpredictable. If
Clinitest is used as a quantitative test for
glycosuria in patients receiving
penicillins, the results should be rechecked using a qualitative method such as the
glucose oxidase tests, Diastix or TesTape. All three tests can be used to test for
glycosuria in patients receiving
aminoglycosides.