SEARCH Articles Figures Tables Dihydrofolate reductase inhibitors interaction with methotrexate Dihydrofolate reductase interaction with methotrexate Dihydrofolate reductase methotrexate active site interaction Mercaptopurine methotrexate, interaction Methotrexate Methotrexate drug interactions Methotrexate interaction with DHFR Methotrexate interaction with dihydrofolate Methotrexate interaction with penicillin Piperacillin interaction with methotrexate