CAS Number: 51-52-5
Small amount of Propylthiouracil can reach the breast milk but it doesn't cause harm to the thyroid function (Low 1979, Kampmann 1980, Cooper 1987). The American Thyroid Association among others (Mandel 2001, Stagnaro 2011, Alexander 2017) stated that a daily dose as high as 450 mg is safe while breastfeeding. However, some studies have shown no harmful effect at a daily dose as high as 750 mg (Kampmann 1980, McDougall 1986, Cooper 1987, Momotani 1989 y 2000, Bartalena 2005, Azizi 2006, Marx 2008, Inoue 2009, Glatstein 2009). Methimazole or Carbimazole is preferred since liver toxicity has been found among patients who were treated with Propylthiouracil (Karras 2009, 2010 y 2012, Azizi 2011, Serrano 2014, Hudzik 2016). The American Academy of Pediatrics has rated it (2001) as compatible with breastfeeding. Eleventh WHO Model List of Essential Drugs 2002: Compatible with breastfeeding.
CAS Number: 51-52-5
Propylthiouracil (PTU) had been considered the antithyroid drug of choice during lactation; however, findings that the rates of liver injury higher with PTU than with methimazole has altered this judgement. Some experts now recommend that methimazole should be considered the antithyroid drug of choice in nursing mothers. No cases of PTU-induced liver damage have been reported in breastfed infants and it is unknown if the small amounts of the drug in breastmilk can cause liver damage. The drug or breastfeeding should be discontinued if liver toxicity is suspected. Dosages of PTU should be limited to 450 mg daily during breastfeeding. The American Thyroid Association recommends only monitoring infants for appropriate growth and development during routine pediatric health and wellness evaluations and routine assessment of serum thyroid function in the child is not recommended. Rare idiosyncratic reactions (e.g., agranulocytosis) might occur, and the infant should be watched for signs of infection. Monitoring of the infant's complete blood count and differential is advisable if there is a suspicion of a drug-induced blood dyscrasia.
As usage of Propylthiouracil 50 Mg is mostly safe while breastfeeding hence there should not be any concern. In case of any change in behavior or health of your baby you should inform your health care provider about usage of Propylthiouracil 50 Mg else no further action is required.
Definitely, Propylthiouracil 50 Mg is safe in lactation for baby. No wonder your doctor has recommended it.
No extra baby monitoring required while mother is using Propylthiouracil 50 Mg
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