[Stability of beta-lactamase inhibitors and beta-lactam antibiotics in parenteral formulations as well as in body fluids and tissue homogenates. Comparison of sulbactam, clavulanic acid, ampicillin and amoxicillin].

Stability of beta-Lactamase Inhibitors and beta-Lactam Antibiotics in Parenteral Formulations as Well as in Body Fluids and Tissue Homogenates/Comparative studies with sulbactam, clavulanic acid, ampicillin and amoxicillin. The beta-lactamase inhibitors and the beta-lactam antibiotics are markedly different in chemical stability. The comparative examination of 4 different infusion solutions at 4 degrees C, 25 degrees C and 37 degrees C gives the following sequence of decreasing stability: sulbactam (CAS 68373-14-8), ampicillin (CAS 69-53-4), amoxicillin (CAS 61336-70-7) and clavulanic acid (CAS 58001-44-8). It is particularly striking that the two beta-lactamase inhibitors, sulbactam and clavulanic acid, behave very differently. Sulbactam is also much more stable than clavulanic acid to incubation at 37 degrees C in body fluids or in tissue homogenates. The differences in the stability of the individual drugs should be born in mind during clinical use of combination formulations such as sulbactam/ampicillin (Unacid) and clavulanic acid/amoxicillin.