Enhanced rectal absorption of cefmetazole and cefoxitin in the presence of epinephrine metabolites in rats and a high-performance liquid chromatographic assay for cephamycin antibiotics
Nishihata, T.; Takahagi, H.; Yamamoto, M.; Tomida, H.; Rytting, J.H.; Higuchi, T.
Journal of Pharmaceutical Sciences 73(1): 109-112
ISSN/ISBN: 0022-3549 PMID: 6582265 DOI: 10.1002/jps.2600730129
4-Hydroxy-3-methoxymandelic acid and 3,4-dihydroxymandelic acid were potent adjuvants for the rectal absorption of water-soluble compounds in rats. Both adjuvants enhanced the absorption of 2 cephamycin antibiotics, cefmetazole and cefoxitin. Maximum plasma levels of the antibiotics were obtained within 30 min after rectal administration. The bioavailability of both antibiotics appeared to depend on the concentration of the adjuvant in the microenema, the dosage form used in these experiments. Instead of a microbial assay, a new chemical method involving high-performance liquid chromatography with an ion-pairing technique was developed for analyzing the cephamycin antibiotic plasma levels.