Combined aztreonam and gentamicin therapy for pseudomonal lower respiratory tract infections.

A multicenter, open-label study was performed to assess the efficacy and safety of aztreonam plus gentamicin in the treatment of lower respiratory tract infections due to Pseudomonas aeruginosa. Patients with documented P aeruginosa infections were given aztreonam 2 g every 8 hours (q8h) plus gentamicin 3 to 5 mg/kg per day in three equal doses. Clindamycin, 600 mg q8h, was added to the regimen for patients with infections also involving gram-positive and/or anaerobic bacteria.