Mastitis While Breastfeeding: Symptoms, Treatment, and When to Get Help
Key takeaways
- Mastitis is inflammation of the breast: a hot, painful, red area in one breast, often with flu-like symptoms such as aches, chills, or a fever.
- Keep feeding or removing milk from the affected breast; continuing to drain it is part of the treatment and your milk stays safe for your baby.
- Rest, fluids, gentle care, and suitable pain relief help; avoid aggressive massage and over-pumping, which can make inflammation worse.
- Seek medical help if symptoms do not improve within about 24 hours, if you feel very unwell, or if symptoms are severe from the start, as you may need antibiotics.
- Mastitis is unpleasant but treatable, and it is not a reason you have to stop breastfeeding.
Mastitis is inflammation of the breast, usually a hot, painful, red area in one breast often with flu-like symptoms or a fever, and the core of treatment is to keep removing milk, rest, and seek medical help if it does not settle within about 24 hours or you feel unwell. It is unpleasant but treatable, and it is not a reason you have to stop breastfeeding.
I had mastitis at about three weeks with my first baby, and it floored me. One minute I had a sore spot, and by that evening I was shivering under a blanket with a fever, aching all over, certain I had the flu. It was mastitis, and once I understood that the answer was to keep feeding rather than stop, and got the right help, it cleared within a few days. Here is what to recognise and do, reviewed by a paediatrician.
What is mastitis?
Mastitis is inflammation of the breast tissue, which can occur with or without infection. It often develops when milk is not draining well, for example after an unrelieved blocked duct or engorgement, and bacteria can sometimes enter through a cracked nipple. The breast becomes inflamed, and you feel unwell with it.
The defining feature, and the thing that sets it apart from a simple blocked duct, is that with mastitis you feel ill in yourself, not just locally sore. Where a blocked duct is a tender lump while you otherwise feel fine, mastitis comes with the flu-like, feverish feeling. It belongs in the wider set of breast problems covered in our breastfeeding pillar.
Symptoms to recognise
The hallmark of mastitis is a hot, painful, red, or swollen area in one breast together with feeling unwell. Common symptoms include:
- A hot, tender, reddened, or swollen patch on one breast, often wedge-shaped.
- Flu-like symptoms: body aches, chills, and tiredness.
- A fever.
- A general sense of feeling ill that came on alongside the breast pain.
It usually affects one breast and often follows a blocked duct or a stretch where the breast was not well drained. If you have a hot, painful area and you feel unwell, treat it as possible mastitis and act early.
Keep feeding and removing milk
Continuing to remove milk from the affected breast is part of the treatment, not something to avoid, and your milk stays safe for your baby. Keeping milk moving relieves the build-up that is driving the inflammation, so feed frequently, offer the affected side, and drain the breast as comfortably as you can. Newborns feed about 8 to 12 times in 24 hours anyway, and that frequency works in your favour here.
Stopping feeding suddenly on the sore side tends to make mastitis worse by letting milk build up further. If feeding is too painful, gentle hand expression keeps milk moving while you arrange help. A deep latch helps the breast empty, so check how to get a good latch if feeding is not draining the area.
Rest, fluids, and gentle care
Alongside keeping milk moving, rest is genuinely part of recovery, not a luxury. Rest as much as you can, stay hydrated, and use pain relief that is suitable for you, which also reduces the inflammation. Brief warmth before a feed helps milk flow, and a cool compress afterward soothes.
As with a blocked duct, be gentle. Avoid aggressive massage and over-pumping, which can increase swelling and inflammation. Current guidance, including from the Academy of Breastfeeding Medicine, favours gentle care and normal milk removal over forceful measures. Look after yourself; being run down is part of how mastitis takes hold.
When to seek medical help
Seek medical help if your symptoms do not improve within about 24 hours, if they are severe from the start, or if you feel very unwell, because you may need antibiotics. Mastitis can progress quickly, so this is one to act on rather than wait out. Tell your doctor you are breastfeeding so that any medicine prescribed is compatible, and if you are given antibiotics, finish the full course. If you have a cracked nipple that looks infected, mention that too, as it can be the source.
Get urgent help if you become very unwell, if a red, painful area is spreading rapidly, or if a firm, very tender swelling develops that does not drain, which can occasionally point to an abscess needing specific treatment.
You do not have to stop
Mastitis is treatable, and having it does not mean you have to stop breastfeeding. In fact stopping abruptly can make it worse. With prompt milk removal, rest, and medical help when needed, most people are through it within a few days and go on feeding happily, as I did. This is general information and not a substitute for advice about your own situation, so please get checked if you are not improving. If you would like ongoing support, a midwife, health visitor, IBCLC lactation consultant, or your doctor can help, and the emotional side of breastfeeding matters too when you are feeling this rough.
References
- Breastfeeding, World Health Organization.
- Breastfeeding, NHS.
- Academy of Breastfeeding Medicine, Academy of Breastfeeding Medicine.
- Breastfeeding, American Academy of Pediatrics (HealthyChildren.org).
Frequently asked questions
What are the symptoms of mastitis?
Mastitis typically causes a hot, painful, red, or swollen area in one breast, together with feeling unwell in yourself. Many people also have flu-like symptoms such as body aches, chills, tiredness, and a fever. It often follows a blocked duct or engorgement that did not clear. The key difference from a simple blocked duct is that with mastitis you feel ill, not just sore. If you have these symptoms, keep removing milk, rest, and seek medical help if they do not settle within 24 hours or you feel very unwell.
Should I keep breastfeeding with mastitis?
Yes. Continuing to feed or express from the affected breast is an important part of treatment, because keeping milk moving helps relieve the inflammation. Your milk remains safe for your baby even with mastitis. Stopping feeding suddenly on that side tends to make things worse by letting milk build up. Feed frequently, offer the affected side, and drain the breast as comfortably as you can. If feeding is too painful, gentle hand expression keeps milk moving while you get help.
How long does mastitis take to clear up?
Mild mastitis caught early can start to improve within about 24 hours of keeping milk moving, resting, and using suitable pain relief. If it does not improve within roughly 24 hours, if it is getting worse, or if you feel very unwell, you should seek medical help, as you may need antibiotics. With antibiotics, symptoms usually improve within a couple of days, and it is important to finish the full course. Tell your doctor you are breastfeeding so any medicine prescribed is compatible.
Do I always need antibiotics for mastitis?
Not always. Early, mild mastitis can sometimes settle with frequent milk removal, rest, fluids, and pain relief alone. Antibiotics are needed when symptoms are severe from the start, when they do not improve within about 24 hours of those measures, or when there is an infected nipple crack or you are feeling very unwell. Because mastitis can worsen quickly, do not wait too long: if you are not clearly improving within 24 hours, get medical advice rather than pushing on.
How do I prevent mastitis?
Prevent mastitis by keeping milk flowing freely and treating blocked ducts and engorgement promptly. Feed regularly and drain the breast well, get a deep latch so the breast empties effectively, avoid tight bras and pressure on the breast, and vary your feeding positions. Look after yourself with rest and fluids, since being run down can play a part. Address any sore, cracked nipples quickly, as a break in the skin can let infection in. If you keep getting mastitis, see an IBCLC lactation consultant to find the cause.
Written by Sophie Bennett. Medically reviewed byDr Amara Okafor, MBBS, MRCPCH.
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