Objectives: This study has been done to evaluate the interaction between ethanolic extracts of Rhus coriaria (seed), Psidium guajava (Leaf), Lawsonia inermis (Leaf) and Sacropoterium spinosum (seed) and antimicrobial drugs including oxytetracycline HCl, enrofloxacin, gentamicin sulphate and sulfadimethoxine against four clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA).

Methodology: Evaluation of the interaction between ethanolic extracts and different antimicrobial agents has been done using well-diffusion method.

Results: It showed that ethanolic extracts increase the inhibition zones of oxytetracycline HCl, gentamicin sulphate, and sulfadimethoxine, while combinations between these plant extracts and enrofloxacin decrease inhibition zone.

Conclusion: This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S. aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics.