Abstract: A total of 36 samples of three sulphur containing drugs, viz.: chlorpropamide, Ampicillin and frusemide from three different companies labelled A, B and C commonly dispensed to officers, cadets and civilian staff of the Nigerian Defence Academy were tested for their potency using the U.V spectrophotometer assay method. The total drug content, percentage active ingredients, chemical assay and dissolution rate studies for the drugs were evaluated. The specified chemical tests were carried out on the samples analysed and the results were in conformity with that described in BP 1993. The drug contents and percentage active ingredients were found to be within acceptable limit of the monograph. The dissolution rate study of chlorpropamide using the BP 1993 method and pH dependent dissolution rate studies of Ampicillin and Frusemide were investigated on physiological buffer solution pH 6.8. The results obtained demonstrated very good dissolution rate profiles and are discussed in the light of high rate of faking, adulteration and manufacture of substandard drugs and their implication.