Possible Interaction: Homocysteine and Metformin

“In the literature, only one study has demonstrated that metformin increases Hcy levels in PCOS patients, but the effect of other insulin sensitizers on Hcy levels have not been reported previously in women with PCOS.”

“The homocysteine level in PCOS patients was significantly increased after taking metformin (mean difference [MD] -1.33; 95% confidence interval [CI] -2.16 to -0.49, p = 0.002).”

“Anti-diabetic drugs such as metformin by affecting vitamin B12 levels can also affect homocysteine.”

“Correlation between B12 and homocysteine was stronger in metformin-treated (P<0.01, r=-0.48) than non-metformin-treated (P=0.04, r=-0.38) patients.”

“There were independent correlations between metformin use and B12 lowering (P=0.02, r = -0.25), and B12 lowering and elevation of homocysteine (P<0.01, r=-0.34).”

“Finally, metformin , some lipid-lowering drugs, and some diuretics should be avoided because they can increase Hcy levels.”

“Long-term use of metformin is associated with malabsorption of vitamin B12 (cobalamin [Cbl]) and elevated homocysteine ( Hcy ) and methylmalonic acid (MMA) levels, which may have deleterious effects on peripheral nerves.”

“However, metformin increases levels of homocysteine (Hcy), considered an independent risk factor for atherosclerosis.”

“Plasma homocysteine levels were significantly reduced by both B vitamins and metformin , but to a greater degree by B vitamins, and higher pregnancy rates were associated with vitamin B treatment.”

“Several widely used drugs, such as lipid-lowering drugs (like fibrates and niacin) or oral hypoglycemic drugs (like metformin ), insulin, drugs used in rheumatoid arthritis, and anticonvulsants cause elevated tHcy concentrations.”

“The plasma Hcy levels showed a significant correlation with the duration of metformin treatment (p = 0.014) and the amount of metformin received (p = 0.015) with the Spearman correlation coefficient of 0.260 and 0.258 respectively.”