Possible Interaction: Folic Acid and Methotrexate

“CONCLUSION The results of our study suggest that the MTHFR 677T and 1298C alleles may be associated with an increased rate of RA remission in patients treated with MTX receiving high doses of folic acid supplementation.”

“ CONCLUSION The results of our study suggest that the MTHFR 677T and 1298C alleles may be associated with an increased rate of RA remission in patients treated with MTX receiving high doses of folic acid supplementation.”

“OBJECTIVES This study investigated whether: (i) rheumatoid arthritis (RA) patients have more micronuclei (MN) than healthy controls; (ii) methotrexate (MTX) treated RA patients have more MN than those not using MTX, and (iii) folic acid supplementation decreases the number of MN in MTX treated patients.”

“This study investigated whether: (i) rheumatoid arthritis (RA) patients have more micronuclei (MN) than healthy controls; (ii) methotrexate (MTX) treated RA patients have more MN than those not using MTX, and (iii) folic acid supplementation decreases the number of MN in MTX treated patients. ”

“Supplementation with folic or folinic acid reduced the risk of toxicity-related discontinuation of MTX treatment both in patients with and in patients without the mutation.”

“RESULTS Folic acid supplementation led to reduced plasma MTX levels 2 and 8 h after MTX administration and reduced area under the plasma MTX concentration versus time curve (AUC) (about 20%; p < 0.02).”

“ RESULTS Folic acid supplementation led to reduced plasma MTX levels 2 and 8 h after MTX administration and reduced area under the plasma MTX concentration versus time curve (AUC) (about 20%; p < 0.02).”

“These results reopen the question of whether folic acid should be used immediately in all patients when MTX is begun.”

“Total clearance of MTX and Vd were higher when patients were also receiving folic acid than when they were taking MTX alone (p < 0.02).”

“RESULTS MTX treated patients had lower FA levels than controls (median 4.36 vs 7.37 ng/ml, p < 0.001).”

“ RESULTS MTX treated patients had lower FA levels than controls (median 4.36 vs 7.37 ng/ml, p < 0.001).”

“ Folic acid supplementation has been reported anecdotally to lessen toxicity in patients receiving methotrexate treatment [27, 28].”

“In a 6-month, double-blind, placebo-controlled trial, 7 mg of folic acid weekly (1 mg/d or 2265 nmol/d) decreased methotrexate toxicity without affecting efficacy [29].”

“The influence of the folic acid dose on methotrexate toxicity and efficacy remains controversial, and the effects of different doses of folic acid are not known [37, 38].”

“In addition, folic acid and thiamine monophosphate, RFC inhibitors, inhibited the uptake of MTX from the basolateral side of the H441 cells.”

“In addition, RA patients with the MTHFR C677T polymorphism who were supplemented with folic acid displayed significantly elevated risk for MTX toxicity. ”

“In addition, RA patients with the MTHFR C677T polymorphism who were supplemented with folic acid displayed significantly elevated risk for MTX toxicity.”

“Therefore, folic acid should be used daily with methotrexate to ameliorate side effects, whereas folinic acid should only be used for methotrexate toxicity.”

“IntroductionThere is reasonable evidence that folic acid 5–10 mg per week leads to reduction in methotrexate (MTX) toxicity in rheumatoid arthritis (RA).”