Last update May 5, 2022
Nirmatrelvir is an antiviral protease inhibitor with emergency use authorization for the treatment of coronavirus disease 2019 (COVID-19) in adults who do not require supplemental oxygen delivery and who are at high risk for progression to severe COVID-19, including hospitalization or death (EMA 2022, FDA 2022). It is given together with Ritonavir to increase its bioavailability, which is low. (Mikus 2022)
At the date of the last update we did not find any published data on its excretion in breast milk.
Its pharmacokinetic data (very wide volume of distribution and moderately high molecular weight) make it highly unlikely that significant quantities will pass into breast milk.
Its low oral bioavailability minimizes the passage into plasma of the infant from ingested breast milk, except in the premature and in the immediate neonatal period in which there may be greater intestinal permeability.
Possible side effects are neither frequent nor serious. (EMA 2022, FDA 2022)
Expert authors consider the use of this medication possible during breastfeeding. (Anderson 2022)
Suggestions made at e-lactancia are done by APILAM team of health professionals, and are based on updated scientific publications. It is not intended to replace the relationship you have with your doctor but to compound it. The pharmaceutical industry contraindicates breastfeeding, mistakenly and without scientific reasons, in most of the drug data sheets.
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