Is Metformin Hydrochloride compatible with breastfeeding? Do we have alternatives for Metformin Hydrochloride?

Metformin Hydrochloride

March 22, 2018 (Very Low Risk)

Oral antidiabetic medication used for treatment of Diabetes Type II, Obesity and Polycystic Ovarian Syndrome (PCOS). Biguanide drugs act by decreasing Neoglycogenesis (new formation of sugar) in the liver. Low risk of Hypoglycemia.

Metformin is excreted into breast milk in non-significant amount and without harmful effect on breastfed infants of treated mothers,

Obesity is associated with breastfeeding difficulties. In spite of Metformin has beneficial effect on Obesity, this is not true with PCOS because lactation capacity is related to growth of breast tissue during pregnancy which is not improved by the use of Metformin,

Oral antidiabetic drugs are not effective for Diabetes Type I. For Diabetes Type II diet, physical exercise and breastfeeding may ameliorate glycemia levels. See remarks on mother's Diabetes Mellitus by consulting specific item.


We do not have alternatives for Metformin Hydrochloride since it is relatively safe.

Very Low Risk

Compatible. Not risky for breastfeeding or infant.

Low Risk

Moderately safe. Mild risk possible. Follow up recommended. Read the Comment.

High Risk

Poorly safe. Evaluate carefully. Use a safer alternative. Read the Comment.

Very High Risk

Not recommended. Cessation of breastfeeding or alternative.


  • Μετφορμίνη υδροχλωρική (Greek)
  • Метформина Гидрохлорид (Cyrillic)
  • メトホルミン塩酸塩 (Japanese)
  • C4 H11 N5, HCl (Molecular formula)
  • 1,1-Dimethylbiguanide hydrochloride (Chemical name)
  • A10BA02 (ATC Code/s)

Drug trade names


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