[Resorption of orally administered antibiotics and chemotherapeutic drugs and their effect. Part 1].

There are considerable differences in the oral absorption of antibiotics. Different groups of drugs and different galenic preparations of the same compound show vast differences in their bioavailability. This is not without therapeutic consequences. These differences depend on water and lipid solubility of drugs, the dissociation constant and polarity of the side chains. The first part describes methods of determination of serum and urine concentrations. The determination of pharmakokinetic parameters allows an assessment of the bioavailability, however there are pitfalls, by overemphasizing a single parameter in the calculation. We are able to demonstrate differences in the resorption of various penicillin salts, and of different aminopenicillins in dependence of their side chains with differences in their polarity. It should be stressed, that only the calculation and consideration of all pharmakokinetic parameters together allows a fair assessment of the quality of absorption of an antibiotic.