Reproductive health
Medicines for Mastitis
A painful inflammation of breast tissue most common in breastfeeding women, where the key to recovery is keeping the breast well drained by continuing to breastfeed or express, with antibiotics added only if there is a clear infection or it is not improving.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Mastitis?
Mastitis is inflammation of the breast tissue that makes an area of the breast red, hot, swollen and tender, often accompanied by flu-like symptoms such as aches, chills and a raised temperature. It is most common in women who are breastfeeding, usually in the first few weeks, and the usual cause is milk not draining properly from part of the breast — often starting as a blocked duct.
- How it is treated: The most important part of managing mastitis is keeping the affected breast well drained, because the inflammation is driven by milk that is not flowing properly.
- Self-care: Continuing to breastfeed or express to keep the breast drained, ensuring the baby is well latched, feeding frequently and not suddenly stopping breastfeeding, resting, drinking plenty of fluids, and using warmth before feeds and a cold compress afterwards all support recovery.
- When to seek help: See your GP, midwife or health visitor if your symptoms do not start to improve within about 12 to 24 hours of keeping the breast well drained, if you feel increasingly unwell, or if there are signs of infection such as a high temperature, a cracked nipple, or worsening redness and pain.
What it is
Mastitis is inflammation of the breast tissue that makes an area of the breast red, hot, swollen and tender, often accompanied by flu-like symptoms such as aches, chills and a raised temperature. It is most common in women who are breastfeeding, usually in the first few weeks, and the usual cause is milk not draining properly from part of the breast — often starting as a blocked duct. The pooled milk causes inflammation, and sometimes bacteria then take hold and cause an infection on top. It typically affects one breast and usually only part of it. Although it can feel quite unpleasant and make you feel unwell, mastitis is common and usually settles with the right care. Importantly, it is safe to keep breastfeeding from the affected breast — the milk is not harmful to the baby, and continuing to feed actually helps the breast to drain and recover. Mastitis can occasionally occur in women who are not breastfeeding too. Persistent or unusual breast changes should always be checked, as in rare cases a long-standing, non-resolving change can be a sign of an inflammatory breast cancer that needs to be excluded.
How it is treated
The most important part of managing mastitis is keeping the affected breast well drained, because the inflammation is driven by milk that is not flowing properly. For breastfeeding women this means continuing to breastfeed frequently, starting with or paying particular attention to the affected side, and expressing any remaining milk if the breast still feels full after a feed. Getting the baby to latch well, and gentle measures such as warmth before a feed to help the milk flow and a cold compress afterwards to ease swelling, all help. Rest, plenty of fluids and simple pain relief make a real difference. With good drainage and self-care, many cases settle within a day or two. An antibiotic — typically flucloxacillin, a penicillin — is added when there are clear signs of infection, when symptoms are not improving despite good drainage, or when a nipple has a crack that is infected. If an antibiotic is prescribed, it is still important to keep draining the breast and to finish the course. Help from a midwife, health visitor or breastfeeding support service with positioning and attachment can prevent it happening again.
For this condition, these medicines
Medicine classes used for Mastitis
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Symptom checker
Symptoms that can point to Mastitis
Mastitis can be one cause of these symptoms. Each guide explains the other possible causes and the red-flag warning signs that mean you should get urgent help:
Beyond medication
Lifestyle and self-care
Continuing to breastfeed or express to keep the breast drained, ensuring the baby is well latched, feeding frequently and not suddenly stopping breastfeeding, resting, drinking plenty of fluids, and using warmth before feeds and a cold compress afterwards all support recovery. Getting practical help with positioning and attachment from a midwife, health visitor or breastfeeding supporter can reduce the chance of mastitis coming back.
When to get help
When to see a doctor
See your GP, midwife or health visitor if your symptoms do not start to improve within about 12 to 24 hours of keeping the breast well drained, if you feel increasingly unwell, or if there are signs of infection such as a high temperature, a cracked nipple, or worsening redness and pain. Seek prompt review if you develop a painful, firm or fluctuant lump that is not settling, as this can indicate a breast abscess that may need draining. Any persistent change in the breast that does not fully resolve after treatment should be assessed, as in rare cases this is needed to exclude an inflammatory breast cancer.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Mastitis: frequently asked questions
What medicines are used for mastitis?
Many cases of mastitis settle without antibiotics, simply by keeping the breast well drained, resting and using pain relief. When there are clear signs of infection, when symptoms are not improving despite good drainage, or when a cracked nipple has become infected, an antibiotic is added — most commonly flucloxacillin, which is a penicillin. If you are prescribed an antibiotic it is important to keep breastfeeding or expressing to drain the breast and to finish the whole course. Paracetamol or ibuprofen can be used for the pain and fever.
Is it safe to keep breastfeeding with mastitis?
Yes — and not only is it safe, it is the single most helpful thing you can do. Continuing to breastfeed from the affected breast helps drain the pooled milk that is causing the inflammation, which is exactly what the breast needs to recover. The milk is not harmful to your baby. Suddenly stopping feeding tends to make mastitis worse because the breast becomes more engorged. Feeding frequently, starting on the sore side, and expressing any milk left after a feed all help the breast to clear and settle.
How can I tell mastitis from a simple blocked duct?
A blocked duct usually feels like a tender lump or firm area in the breast without making you feel generally unwell, and it often eases with frequent feeding and gentle drainage. Mastitis is further along the same spectrum: the area becomes red, hot, swollen and painful, and you typically feel unwell with flu-like symptoms such as aches, chills and a raised temperature. A blocked duct can progress to mastitis if the milk is not cleared, which is why prompt attention to drainage helps at either stage. If flu-like symptoms appear or things are not improving, it is worth seeking advice.
Can mastitis happen if I am not breastfeeding?
Yes, although it is much less common. Mastitis can occasionally affect women who are not breastfeeding, and it can also affect the area around the nipple, sometimes linked to a blocked or inflamed duct or, occasionally, smoking. Whatever the situation, any breast inflammation that does not settle, or any persistent lump or skin change, should be assessed by a doctor. This is partly to make sure it is treated properly and partly because, in rare cases, a non-resolving breast change needs checking to exclude an inflammatory breast cancer.
Keep reading
Related articles
Sources
Where this is drawn from
- NICE CKS: Mastitis and breast abscess.
- BNF: Flucloxacillin.
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