Evaluation of metoclopramide syrups by Bratton-Marshall method

Abstract

Nowadays, most of the drugs have amine group in their structure. These drugs, when associated to sugar reducers, or other carbonyl excipients frequently produce dark stains or fading. The Maillard reaction can explain such occurrence. In this work, we have studied the behavior of syrups containing aromatic amines. It is known that association of sugars and amines can generate problems of stability. The chosen prototype was the metoclopramide hydrochloride, a benzamide, with anti-emetic pharmacological activity. Samples of the metoclopramide syrups were maintained in stove at 40 °C for six months. In regular time intervals aliquots were removed and submitted to quantitative determination by the Bratton-Marshall's method, followed by a spectrophotometric determination. There was not great variation of the metoclopramide level in relation to sugar level, once metoclopramide samples were prepared in different sugar levels. There was a decrease of the metoclopramide level, over 50%, for commercial and standardized samples, after a period in stove