Because no information is available on the use of systemic dexamethasone during breastfeeding, an alternate corticosteroid may be preferred, especially while nursing a newborn or preterm infant. Local injections, such as for tendinitis, would not be expected to cause any adverse effects in breastfed infants, but might occasionally cause temporary loss of milk supply.

Topical dexamethasone has not been studied during breastfeeding. Since only extensive application of the most potent corticosteroids cause systemic effects in the mother, it is unlikely that short-term application of topical corticosteroids would pose a risk to the breastfed infant by passage into breastmilk. However, it would be prudent to use the least potent drug on the smallest area of skin possible. It is particularly important to ensure that the infant's skin does not come into direct contact with the areas of skin that have been treated. Only the lower potency corticosteroids (e.g., hydrocortisone, triamcinolone) should be used on the nipple or areola where the infant could directly ingest the drugs from the skin. Only water-miscible cream or gel products should be applied to the breast because ointments may expose the infant to high levels of mineral paraffins via licking.[1] Any topical corticosteroid should be wiped off thoroughly prior to nursing if it is being applied to the breast or nipple area. Because absorption from the eye is limited, ophthalmic dexamethasone would not be expected to cause any adverse effects in breastfed infants. To substantially diminish the amount of drug that reaches the breastmilk after using eye drops, place pressure over the tear duct by the corner of the eye for 1 minute or more, then remove the excess solution with an absorbent tissue.