Carbenicillin and gentamicin were tested on rats experimentally burned and infected by a selected strain of Pseudomonas aeruginosa. Carbenicillin injection was found to be the best treatment as it decreased pus formation and enhanced healing. Gentamicin was less effective than carbenicillin. The use of hydrophilic base ointment containing antibiotics is contraindicated, as it probably provides a favourable environment for Pseudomonas aeruginosa growth. The administration of supernatant vaccines and cell vaccines alone and in conjunction with the antibiotics did not modify the course of infection and healing.