<unk>  for systemic administration is available as immediate-release tablets, extended-release tablets, an oral suspension, and as a solution for intravenous administration. When administered over one hour as an intravenous infusion,<unk>  rapidly distributes into the tissues, with levels in some tissues exceeding those in the serum. Penetration into the central nervous system is relatively modest, with cerebrospinal fluid levels normally less than 10% of peak serum concentrations. The serum half-life of<unk>  is about 4–6 hours, with 50–70% of an administered dose being excreted in the urine as unmetabolized drug. An additional 10% is excreted in urine as metabolites. Urinary excretion is virtually complete 24 hours after administration. Dose adjustment is required in the elderly and in those with renal impairment.<unk>  is weakly bound to serum proteins (20–40%). It is an inhibitor of the drug-metabolizing enzyme cytochrome P450 1A2, which leads to the potential for clinically important drug interactions with drugs metabolized by that enzyme.<unk>  is about 70% orally available when administered orally, so a slightly higher dose is needed to achieve the same exposure when switching from IV to oral administration The extended release oral tablets allow once-daily administration by releasing the drug more slowly in the gastrointestinal tract. These tablets contain 35% of the administered dose in an immediate-release form and 65% in a slow-release matrix. Maximum serum concentrations are achieved between 1 and 4 hours after administration. Compared to the 250- and 500-mg immediate-release tablets, the 500-mg and 1000-mg XR tablets provide higher Cmax, but the 24‑hour AUCs are equivalent.<unk>  immediate-release tablets contain<unk>  as the hydrochloride salt, and the XR tablets contain a mixture of the hydrochloride salt as the free base.
Ciprofloxacin
Norfloxacin
Meropenem
Sparfloxacin
Colistin
Ofloxacin
Cethromycin
Metronidazole