Abstract
Phenothiazine reagent in the presence of potassium dichromate was used for determination of loperamide (LPM) depending on oxidative - coupling reaction to create a blue soluble measured at 625 nm against blank solution, the absorbances values exhibit clear and close relation with the real amount of LPM. Linearity was from 0.8 to 40 μg.ml-1 of LPM. Molar absorptivity was 0.3799×104 l.mol-1.cm-1, Sandell's sensitivity was 0.1351μg ∕cm 2, limit of detection and limit of quantitation were 0.33918, and 1.1306 μg /ml respectively. The method was used for determination of three dosage forms of LPM; Loperamide 2 mg/tablets Medochemie Ltd, Limassol-Cyprus (Europe), Loperamide 2 mg/tablets Safa Co. - Diala (Iraq) and Loperamide 2 mg/capsules Janssen pharmaceuticals (Belgium).