Adult: 3 mg/kg/d in three equal doses IM or IV q8h; reduce dose in renal failure; 300 mg b.i.d. by nebulizer. Pediatric: 300 mg b.i.d. by nebulizer Short-term IV or IM treatment of serious infections; occular infections caused by susceptible bacteria; nebulizer management of cystic fibrosis and P. (Pseudomonas) aeruginosa infections