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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.

The concentration of sulfadimidine was measured in the urine of pigs which were housed (over five days) in boxes where other pigs have been treated orally with sulfadimidine before. Sulfadimidine was measured in the urine of the unmedicated pigs in a concentration of up to 4 micrograms/ml. Considering these urine concentrations, violative sulfadimidine tissue residues would be expectable in the carcass after slaughter. The practice of fixing withdrawal times must be considered again to ensure that drug residues in tissues are below the MRL before slaughter also in unmedicated animals.

In a large pig production unit 60 postparturient sows were divided at random into 3 groups, each with 20 sows. Group 1 (20 sows) received 30 g Farmavet Trisulfa per os daily from the beginning of the postfarrowing period for 1 week. Group 2 (20 sows) received 30 g Farmavet Trisulfa per os daily from the beginning of the postfarrowing period for 1 week, and in addition were given 3 mg Gabbrostim 24-48 hours after farrowing in a single i.m. application. Group 3 (20 sows) untreated control. The following parameters were evaluated: A: number of weaned piglets per sow, B: weaning to service interval in days, C: return to oestrus in percent. Both groups 1 and 2 showed better results when compared to the control group. Group 2 was superior to group 1.

A cocktail of four model substances orally administered to humans is used for simultaneous characterization of phenobarbital and 3-methylcholanthrene inducible forms of cytochrome-P450 and two genetic polymorphisms, the debrisoquine hydroxylation and N-acetylation. The investigations offer the possibility to assess four main processes of hepatic drug metabolism as well as the judgement of alterations in drug elimination. Both acetylation and hydroxylation phenotypes are not influenced after administration of the cocktail compared to the administration of the substances alone. A statistically significant 30.4% increase of mean body residence time could be found only for monomethylaminoantipyrine. The other pharmacokinetic parameters of monomethylaminoantipyrine and caffeine were unchanged. A one-point-determination for the 9 hour serum concentrations of monomethylaminoantipyrine, caffeine and sulfamethazine/acetylsulfamethazine as well as the 0-9 hours urine concentrations of debrisoquin/4-hydroxydebrisoquin will be conceivable by using "normal ranges".

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.

White mice infected intraperitoneally with the RH-strain of Toxoplasma gondii (inoculum size 50,000 to 100,000 free protozoans per mouse) received treatment between the second and eighth day after infection with sulphamethazine-pyrimethamine, sulphamethoxy-diazine-pyrimethamine, trimethoprim-sulphamethoxazole or spiramycin subcutaneously. All untreated controls and all mice of the trimethoprim-sulphamethoxazole and spiramycin-treated groups died during the acute stage (except two mice in the latter group on the 15th day). The mean survival times were 6.5, 7.5 and 7.6 days, respectively. The best results were obtained in the sulphamethazine-pyrimethamine-treated mice; 18 out of 27 survived the 30-day observation period (5 cured), in contrast to only 9 out of 40 sulphamethoxydiazine-pyrimethamine-treated mice. Considering the high pathogenicity of the RH-strain, the differences in immunological defence mechanisms in mice (absence of antibody-activating "accessory factor") and the late commencement of treatment of the infected mice, one can state that the combination of sulphamethoxydiazine-pyrimethamine should also be capable of overcoming acute human toxoplasmosis in pregnancy. Spiramycin, by contrast, should be given only in cases where sulphonamide intolerance exists and must then be given in high doses until delivery. The combination of sulphamethoxazole-trimethoprim cannot be recommended.

The pharmacokinetic properties of sulphaperine-sodium, Mebacid 200, and sulphadimidine-sodium were experimentally established from fowl and mathematically objectivated. The highest half-life for elimination, coupled with low protein fixation, was recorded from sulphadimidine, by comparison of the above three sulphonamides. These data were used in dosage calculations for clinical testing.