Compatibility of a new suppository base with certain pharmaceuticals.

The compatibility of the macromolecular product Novosup-78 (mixture of polyethylene glycol esters with the free acids of sunflower oil and lard) with certain drugs relatively widely used in the suppository formulations was studied. By means of the solubility procedure and the UV spectral technique, significant interactions only with definite amounts from both components can take place. A predominant micellar solubilization in Novosup-78 solutions up to 0.5% was assumed. Taking into consideration the dependences obtained, it was concluded that the minimum ratio of drug to Novosup-78 in the proposed suppository formulations is not favorable for complexation interactions.