Analysis of purity profiles of generic lisinopril tablets marketed in Croatia.

In view of an increasing number of generic drugs emerging, a comparative study was performed including the approved lisinopril preparations in the form of tablets marketed in Croatia, to compare purity profiles of generic drugs versus the original medicinal product. Several batches of each individual medicinal product at different stages of their shelf life were analyzed. Impurities were determined by means of high performance liquid chromatography (HPLC). Impurity profiles were demonstrated to be specific for each individual drug. Original drug, as compared to its generic copies, had the lowest values and also the lowest variability of all the tested parameters--type, total number and content of impurities--suggesting that its manufacturing process is to certain degree better controlled compared to other manufacturers. A characteristic impurity C appearing in all the assessed preparations has the lowest levels in the original drug, whereas the amount of the highest unknown impurity does not exceed 0.10% in any of the analyzed preparations. Although the original drug stands out from all the generic preparations with its purity, it can be generally concluded that, as regarding impurities levels, all the analyzed medicinal products are within the ranges of specification limits; accordingly, it is therefore not expected that, in case of lisinopril tablets, administration of the original drug as compared to any of its generic drugs, will be safer for the patient.