Possible Interaction: Methotrexate and Folate

“Conclusions: MTX toxicity, final dose, and efficacy are influenced by folate supplementation.”

“OBJECTIVE To study (i) the influence of methotrexate (MTX) therapy on homocysteine and folate metabolism in patients with rheumatoid arthritis (RA), (… in the methylenetetrahydrofolate reductase gene (MTHFR) on the change in plasma homocysteine levels during MTX treatment, and (iii) the interference of folate and homocysteine metabolism … treatment with MTX.”

“Folate deficiency occurs frequently in patients with rheumatoid arthritis; further, folate stores are decreased in patients with rheumatoid arthritis who take methotrexate , suggesting that impaired folate status is related to toxicity [24-26].”

“ Methotrexate (MTX) is a commonly used antimetabolite, which inhibits folate and DNA synthesis to be effective in the treatment of various malignancies.”

“Intracellular glucose and folate are depleted in SARS-CoV-2-infected cells, and viral replication is exquisitely sensitive to inhibitors of folate and one-carbon metabolism, notably methotrexate.”

“Inhibition of pathways of folate metabolism involving purine metabolism by MTX , have been traditionally emphasized as important in MTX efficacy.”

“Indeed, the very first cancer chemotherapy, methotrexate , functions by blocking folate metabolism and therefore the synthesis of DNA and RNA and has more recently been successfully applied to other proliferative diseases, namely rheumatoid arthritis.”

“Pharmacological inhibition of folate action by methotrexate during neurulation induces NTDs by inhibiting folate interaction with its uptake systems.”

“In vivo inhibition of the folate pathway via methotrexate administration strongly impaired metastasis without altering growth of the subcutaneous tumor.”

“Import was not affected by high concentrations of the antifolate drugs pyrimethamine and sulfadoxine, but was inhibited by the close folate analogue methotrexate.”