Impede is a combination of safe ingredients that significantly disrupt the extraction and conversion of pseudoephedrine into the dangerous illegal drug methamphetamine, commonly known as meth. This reduction in yield makes Nexafed unsuitable for meth cooks, who will shop elsewhere for the products they prefer. In some communities where pharmacies have replaced older single ingredient pseudoephedrine products with Nexafed, meth labs busts have been reduced up to 90%.1