セフォニシド

説明Cefonicid has an unesterified D-mandelic acid moiety at C-7 and a methylsulfothiotetrazole group at C-3. The latter is related to the MTT moiety mentioned above under cefamandole nafate; however, the clotting problems and Antabuse-like side effects associated with MTT have not been reported with cefonicid. The extra acid group in the C-3 side chain leads to this molecule being sold as an injectable disodium salt. Pain and discomfort at IM sites is experienced by some patients, as is a burning sensation and phlebitis. Cefonicid has a longer half-life than the other members of its group but achieves this at the price of somewhat lower potency against Gram-positive bacteria and aerobes. The drug is somewhat unstable, needs to be protected from light and heat, and may yellow or darken. If modest, however, this does not necessarily mean that the potency has decreased significantly, but overt precipitation does. Kirby-Bauer disk testing may overestimate the sensitivity of β-lactamase–producing bacteria to this agent, so some extra caution in interpretation of laboratory results is required.