If you have a fever of greater than about 101 degrees and flu-like symptoms, or if you have red streaks on your breast and blood or pus in your milk, it is time to call the doctor. While not every case of mastitis may require them, antibiotics are the general standard for treatment. Dicloxacillin is most often prescribed for mastitis, but Keflex and erythromycin are also appropriate. Your doctor will select an antibiotic that will not harm your baby. Antibiotics are generally taken for 10-14 days, and it is important to finish the entire course to prevent your infection from recurring. Keep in mind, though, that antibiotics increase the risk of yeast infections, which can occur on your nipples and in your baby’s mouth (also known as thrush), so keep an eye out for white patches in his mouth that do not go away.
The same measures mentioned above to treat plugged ducts should be used when a plugged duct occurs with mastitis. There is no need to stop breastfeeding. Breast milk contains antibodies that will prevent any bacteria from harming your baby, so drinking milk from the infected breast will not hurt him. It is important to continue nursing so that your milk will flush the bacteria out, and your baby is better-designed than any pump for milk removal.
Occasionally, however, a baby will refuse to nurse on the affected side. When he discovers that milk is not flowing from that side as freely as he likes, he may cry in protest. (This may happen any time you have a plugged duct or mastitis.) Also, he may discover that milk from a recently infected breast has a slightly salty flavor. It may or may not bother him. If your baby refuses to nurse on your plugged or infected breast, it is important to continue to empty it as well as possible yourself, through pumping or hand-expression. (Again, you can also try waiting till he is asleep to offer the breast, since most babies will nurse during their sleep.) Failing to unplug an infected duct puts you at greater risk for a breast abscess, otherwise known here as the worst case scenario.