Drug Levels and Effects:

Summary of Use during Lactation:

The oral bioavailability of phenylephrine is only about 40%,[1] so the drug is unlikely to reach the infant in large amounts. However, intravenous or oral administration of phenylephrine might decrease milk production. Because no information is available on the use of oral phenylephrine during breastfeeding, an alternate drug may be preferred, especially while nursing a newborn or preterm infant.

Phenylephrinenasal spray or ophthalmic drops are less likely to decrease lactation. To substantially diminish the effect of the drug 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.

Drug Levels:

Maternal Levels.

Relevant published information was not found as of the revision date.

Infant Levels.

Relevant published information was not found as of the revision date.

Effects in Breastfed Infants:

Relevant published information was not found as of the revision date.

Possible Effects on Lactation:

Relevant published information in humans was not found as of the revision date. However, animal data indicate that phenylephrine can decrease milk production[2][3] and pseudoephedrine, a pharmacologically similar vasoconstrictor, decreases milk production in nursing mothers after oral use.[4]

Alternate Drugs to Consider:



1. Eccles R. Substitution of phenylephrine for pseudoephedrine as a nasal decongeststant. An illogical way to control methamphetamine abuse. Br J Clin Pharmacol. 2007;63:10-4. PMID:17116124
2. Bruckmaier R, Mayer H, Schams D. Effects of alpha- and beta-adrenergic agonists in intramammary pressure and milk flow in dairy cows. J Dairy Res. 1991;58:411-9. PMID:1684977
3. Inderwies T, Pfaffl MW, Bruckmaier RM. Milking characteristics and their relation to adrenergic receptor mRNA expression and ligand binding in the mammary gland of dairy cows. Domest Anim Endocrinol. 2003;25:275-86. PMID:14550511
4. Aljazaf K, Hale TW, Ilett KF et al. Pseudoephedrine: effects on milk production in women and estimation of infant exposure via breastmilk. Br J Clin Pharmacol. 2003;56:18-24. PMID:12848771

Substance Identification:

Substance Name:


CAS Registry Number:


Drug Class:

  • Adrenergic Agents

  • Adrenergic Alpha-Agonists

  • Antiglaucoma Agents

  • Sympathomimetics

  • Vasoconstrictor Agents

  • Nasal Decongestants

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

    Disclaimer:Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.