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A cocktail of 4 substances (caffeine/CYP1A/CYP1A2, metamizol/CYP2B, debrisoquin/CYP2D6 and sulfamethazine/N-acetyltransferase) was administered to 15 maturity-onset diabetics before and 6 months after insulin therapy (IT) to examine changes in hepatic biotransformation capacity in humans under pathological conditions. Blood and urine samples were taken 6 h after oral administration of the drugs. There were no differences in acetylation- and hydroxylationsphenotyping before or during IT. However, a significant increase in concentration of free sulfamethazine during IT can be interpreted as induction of N-acetyltransferase by poor metabolic control. Comparison of caffeine-concentration showed no significant differences. Obviously in humans CYP1A2 is not influenced by type-II-diabetes mellitus. Concentration of 4-methyl-antityprine (4-MAA), a metabolite of metamizol, was significantly increased during IT. This results shows a possible induction of CYP2B by poor metabolic control.

It is published on new results of research from the institute of the author in which were examined some combined ointment gels putting recently in circulation and new emulsifiers from that may be prepared compositions with suitable rheological stability and large water-absorbing capacity. These systems have suitable thermostability and retentivity of water. The release of many active ingredients were investigated with in-vitro and in-vivo-methods.

The authors determined the release of chloramphenicol, oxytetracycline, neomycin and sulphadimidine from different bases (polyoxethene mass, solid fat, 95% solid fat +5% Span 20). The diffusion of chloramphenicol and sulphadimidine was best from hydrophilic bases; that of oxytetracycline and neomycin, from emulsifier-containing lipophil bases. This may be explained by the solubilities of the pharmaca and by interactions between base and active substance.

Sulphadimidine tablets were prepared using 50% w/w of the following vehicles, Celutab, anhydrous lactose and Avicel. Various disintegrants 5% w/w were also incorporated e.g. Primojel, Veegum F, Amberlite, STA-Rx, Meprogat and Alginate YZ. It was found that the disintegration time of the various tablets containing different disintegrants was considerably decreased. The disintegrants increased also the dissolution rate of the various tablet formulations containing sulphadimidine by different extent. The variations in the dissolution rate among the various tablet formulations may be due to the difference in the nature of the disintegrants and their mechanism of action and possibly their interactions with the drug or the vehicle.