Doripenem (Doribax): the newest addition to the carbapenems.

Carbapenems are a class of antimicrobials structurally related to penicillin. Doripenem, the newest agent in this class, was recently approved by the Food and Drug Administration for the treatment of complicated intra-abdominal infections and complicated urinary tract infections. Its spectrum of activity is similar to that of meropenem and imipenem/cilastatin. Some studies indicate that approximately 29% of carbapenem-resistant Pseudomonas aeruginosa isolates may remain sensitive to doripenem, although the clinical relevance of that finding has not been determined. Clinical studies, which have been published only in abstract form to date, have found doripenem to be similar to comparator agents. The most common adverse effects related to doripenem therapy were headache, nausea, diarrhea, rash, and phlebitis. Doripenem, like the other carbapenems, may also cause seizures. Because of the lack of published data, the lack of clear advantages over meropenem, and the increased cost compared with meropenem, doripenem will not be available for use at Baylor University Medical Center except by infectious diseases specialists.

Posaconazole (Noxafil): a new triazole antifungal agent.

Posaconazole is the newest triazole antifungal agent. It is structurally related to itraconazole and has activity against Candida species, Aspergillus species, Cryptococcus neoformans, the zygomycetes, and other filamentous fungi. Randomized, double-blind trials have shown posaconazole to be at least as efficacious as fluconazole for the prevention of invasive fungal infections in immunocompromised patients. It has also shown promising results in the treatment of various fungal infections refractory to other antifungal therapy. The dose of posaconazole is 200 mg orally three times daily for the prevention of invasive fungal infections and 800 mg daily in two to four divided doses for the treatment of invasive fungal infections refractory to other antifungal treatment. All posaconazole doses should be given with food or a nutritional supplement to enhance absorption. The most common adverse effects reported with posaconazole therapy were fever, diarrhea, nausea, vomiting, and headache. Instances of elevated liver enzyme levels, hyperbilirubinemia, and hepatocellular damage were also noted in clinical trials, and these laboratory values should be monitored during treatment with posaconazole.