Preformulation studies on naproxen suppositories

The results of compatibility studies on a formulation for suppositories containing naproxen sodium, calcium levulinate and a fat base (Monoleno OH-6) are reported. Thermal analysis (DSC) was mainly used for preformulation studies on the components, their mixtures and their reaction products. Naproxen sodium and calcium levulinate were found to interact, depending on experimental conditions, deeply modifying the technological properties if suppositories.