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Tolbutamide Pregnancy and Breastfeeding Warnings

Tolbutamide is also known as: Orinase, Tol-Tab

Tolbutamide Pregnancy Warnings

This drug has been shown to be teratogenic in rats at dose 25 to 100 times the human dose. Isolated reports suggest harm in human pregnancy. This drug is expected to cross the placenta and may cause prolonged hypoglycemia in the neonate. There are no adequate and well controlled studies in pregnant women.

Abnormal blood glucose levels during pregnancy have been associated with a higher incidence of congenital abnormalities. If diet alone is not adequate to maintain guideline recommended blood glucose levels, most experts suggest insulin as the drug of choice to achieve these ranges during pregnancy.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Use should be avoided

US FDA pregnancy category: C

-This drug should not be used in the first trimester of pregnancy; women of childbearing potential should discuss adequate contraception with their healthcare provider.
-Prolonged hypoglycemia has been reported in neonates born to mothers receiving a sulfonylurea at the time of delivery; if this drug is used during pregnancy, it should be discontinued at least 2 weeks before the expected delivery date.
-Most experts recommend insulin use during pregnancy to maintain blood glucose levels as close to normal as possible.

See references

Tolbutamide Breastfeeding Warnings

Breastfeeding is not recommended during use of this drug

Excreted into human milk: Yes

Comments: There is a theoretical risk of hypoglycemia in the nursing infant; if diet alone is adequate for controlling blood glucose in the mother, insulin therapy should be considered.

Low amounts of this drug have been detected in human breastmilk. There is some information to suggest this may be too low to cause harm to the breastfed infant, but the potential for hypoglycemia exists. If used, it is advisable to monitor infant for hypoglycemia.

See references

References for pregnancy information

  1. Product Information. Tolbutamide (tolbutamide). Mylan Pharmaceuticals Inc. 2016.

References for breastfeeding information

  1. Cerner Multum, Inc. UK Summary of Product Characteristics.
  2. United States National Library of Medicine. Toxnet. Toxicology Data Network. 2013.
  3. Product Information. Tolbutamide (tolbutamide). Mylan Pharmaceuticals Inc. 2016.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.