Identification of the Mebendazole Polymorphic Form Present in Raw Materials and Tablets Available in South Africa

AbstractA preformulation study of four different raw materials of mebendazole showed that three samples were polymorph C and the other polymorph A, or a mixture of form A and B. X-ray powder diffractometry and infrared spectroscopy indicated that this powder could be form B, but powder dissolution, for which a much slower dissolution was obtained, suggests polymorph A. Literature prescribes the use of polymorph C pharmaceutically, but generic manufacturers should be aware that forms other than C are still available on the market. The four mebendazole tablets currently available in South Africa were also tested and it was found that all of them contained polymorph C.