AbstractObjectiveThe in vitro antimicrobial susceptibility ofPityrosporum ovalestrains isolated from patients with seborrheic dermatitis was determined.MethodMinimum inhibitory concentrations of a total of 11 agents ‐ including true antifungal, antiseborrheic, and antipsoriatic drugs ‐ were measured.ResultsKetoconazole was the most effective of the tested antifungal agents againstPityrosporum ovalein vitro (minimum inhibitory concentration 0.1 μg/ml). The antiseborrheic agents zinc pyrithione and selenium disulfide showed a good in vitro efficacy againstPityrosporumwith similar minimum inhibitory concentrations. Liquor carbonis detergens and dithranol were also able to inhibit growth ofPityrosporum ovalein vitro, but much higher concentrations were necessary.ConclusionThe tested agents commonly used against seborrheic dermatitis might exert their efficacy, at least in part, due to inhibition ofPityrosporum o