Plugged Ducts and Mastitis

A plugged duct is a plug of milk that sits in a milk duct, causing new milk to “back up”. You may feel a firm or lumpy area in your breast that is more noticeable when your breast is full. If you feel a lumpy area in your breast and your breast is red, you feel achy like you have the flu, or you have a low grade fever (less than 38.4 C or 101 F), you have mastitis, or inflammation of the breast which may or may not involve an infection.

What can you do?

  • Continue to breastfeed your baby frequently (8-12 + times in 24 hours).
  • Rest (go to bed!) and drink plenty of fluids.
  • Apply heat to your breast before breastfeeding to promote drainage. You may also apply a castor oil pack before breastfeeding or pumping: pour castor oil liberally onto a warm, wet washcloth – apply it to the firm or lumpy area on your breast – cover with plastic wrap – apply a heating pad so area feels warm (but not hot) - leave in place for ~20 minutes. Rinse breast with water before breastfeeding or pumping to avoid baby ingesting the castor oil.
  • Massage and compress the firm or lumpy area on your breast while breastfeeding or pumping.
  • Pump the affected breast if your baby does not thoroughly drain the breast after feeding, or if baby refuses the breast.
  • Take ibuprofen to reduce inflammation (up to 400 mg every 4 hours).
  • Two studies have shown benefit from taking Lactobacillus probiotics for mastitis; both studies used Lactobacillus salivarius. This species is present in the “Complete Formula” available at MilkWorks. (Arroyo R, et al. Treatment of infectious mastitis during lactation: antibiotics versus oral administration of lactobacilli isolated from breast milk. Clin Infect Dis. June 15, 2010;50(12):1551–1558. Oral Administration of Lactobacillus Strains Isolated from Breast Milk as an Alternative for the Treatment of Infectious Mastitis during Lactation E. Jiménez et al Appl Environ Microbiol. 2008 August; 74(15): 4650–4655)
  • For recurring mastitis or plugged ducts, consider taking lecithin: 1200 mg, 3-4x/day.


  • You see no change in 12-24 hours (you feel no better),
  • Your fever continues, or goes higher than 101 F,
  • The red area on your breast increases in size, or you see red streaks on your breast,
  • You see blood or pus in your milk, or
  • You have a cracked nipple that appears infected

YOU MAY NEED AN ANTIBIOTIC. Please call your physician. If you are prescribed an antibiotic, take the full prescribed course, and consider taking a multi-strain probiotic as well.