Post-antibiotic effect of cephalexin against isolates of Staphylococcus intermedius obtained from cases of canine pyoderma.

The post-antibiotic effect in vitro (PAE) of cephalexin was determined according to a broth dilution method against 5 isolates of Staphylococcus intermedius obtained from cases of canine pyoderma. Two durations of exposure and 3 concentrations were tested. The PAE increased when time of exposure or concentration increased. The mean PAE ranged from 0.7 to 3.3 h. The PAE of cephalexin against Staph-ylococcus intermedius may be clinically relevant when selecting a dosage regimen to treat pyoderma in dogs.