Ceftazidime, gentamicin, and rifampicin, in combination, kill biofilms of mucoid Pseudomonas aeruginosa.

In continuous flow biofilm cultures in medium resembling cystic fibrosis bronchial secretions, Pseudomonas aeruginosa was not eradicated from biofilms by 1 week of treatment with high concentrations of ceftazidime and gentamicin, to which the strains were sensitive on conventional testing. The addition of rifampicin, which has little activity against the strains as measured by the minimum inhibitory concentration, led to the apparent elimination of the bacteria from the biofilms. The effect was not strain specific.