Fig. 3.

Representative chromatograms from analysis of loperamide. Samples of loperamide, an opioid compound with little central nervous system activity used to treat diarrhea, were analyzed 2 months before the manufacturer expiration date. They contained active ingredient at 96.3% of the label claim of 2 mg per tablet; the lowest amount in a sample was 93.2%. Two additional peaks were observed bracketing the main peak at ≤0.1 and ≤0.8%, respectively