title: Methotrexate:  the pharmacology behind medical treatment for ectopic pregnancy.
abstract: Previously established as a chemotherapeutic agent for decades, methotrexate has been adapted for use as a medical therapy for unruptured ectopic pregnancies. Its mechanism of action, competitive inhibition of folate-dependent steps in nucleic acid synthesis, effectively kills the rapidly dividing ectopic trophoblast. However, the same action on normal cells is the basis for many of its adverse effects.
authors.affiliation: Department of Obstetrics & Gynecology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA. c-stika@northwestern.edu
authors.forename: Catherine S
authors.initials: CS
authors.lastname: Stika
mesh_terms: D000020:Abortifacient Agents, Nonsteroidal / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005493:Folic Acid Antagonists / Q000494:pharmacology; D006801:Humans; D008727:Methotrexate / Q000494:pharmacology*; D011247:Pregnancy; D011271:Pregnancy, Ectopic / Q000188:drug therapy; D013762:Tetrahydrofolate Dehydrogenase
chemical_list: D000020:Abortifacient Agents, Nonsteroidal; D005493:Folic Acid Antagonists; D013762:Tetrahydrofolate Dehydrogenase; D008727:Methotrexate