The formulation of different dosage forms with the anthelmintics : Levamisole, Niclosamide and Oxyclozanide

Abstract

Different formulations of dosage forms of niclosamide, levamisole HCI or levamisole HCI and oxyclozanide have been used on the local market for a very long time. Unfortunately, the spectrum of each of the drugs alone has a very narrow therapeutic index. Together, however, they have a broad spectrum of action and it is a solution to most of the helminths infestations today. Because of the increasing cost to produce livestock, it is important to formulate a product that is not only pharmacologically effective but also cost effective. A combination dosage form plays a big role in decreasing the cost of live stock production in that only one product is bought instead of more. A solution, suspension and tablet were formulated and tested. Niclosamide is very slightly soluble in water and is difficult to solubilise. A solution with niclosamide 3%, oxyclozanide 3.4%, and levamisole HCI 2,5% was formulated. This was done because of the assumption that niclosamide is better absorbed in a solution and that the effective concentration needed is much lower. A suspension and a dispersible tablet with niclosamide 20%, oxyclozanide 3.4%, and levamisole HCI 2,5% was formulated where the tablet is specially formulated to accommodate the smaller live stock farmers. All the above dosage forms were tested under accelerated stability conditions. Physical and chemical tests have been conducted on the dosage forms before and after storage at accelerated stability conditions. An assay was done on each of the three dosage forms where a HPLC method was developed and validated as there is no method in the literature that describe the simultaneous analyses of levamisole HCI, niclosamide and oxyclozanide in a dosage form. The results of al three dosage forms were very encouraging. The solution proved to be the most promising of all the formulations, and it might be worth while to put such a product on the market.