Oxybutynin effects on Staphylococcus epidermidis biofilm production

Oxybutynin is a tertiary amine and has chemical similarities like protamine sulfate. Protamine sulfate's effect on bacterial viability has been shown in some studies; however, there is scanty data regarding the effect of oxybutynin on bacterial viability. Accordingly, the aim of the present study was to investigate the effect of oxybutynin on bacterial viability.

Twenty of Staphylococcus epidermidis (S. epidermidis) strains were isolated from patients who had catheter-associated urinary tract infection. These strains were exposed to 5 different concentrations of oxybutynin in tryptic soy broth (TSB) media (max: 5 mg/mL, min: 0.05 mg/mL). Quantitative growth patterns were measured by spectrophotometer. Under the same media conditions, biofilm production of individual strains was measured by Deighton's micromethod at the end of the 6-hour incubation period.

After the incubation period, weak and strong slime-producing bacteria groups were obtained and both groups' slime productions were extensively low at 5 mg/mL concentration of oxybutynin. Slime production of S. epidermidis was inversely correlated with oxybutynin concentrations.

Although there was a dose-dependent reduction of biofilm production, there seemed to be no bactericidal effect of oxybutynin on S. epidermidis.