Breast Abscess in Singapore: When Mastitis Turns to Pus

Written & reviewed by the BestDoctors.sg editorial team · Last updated 25 Aug 2026 · General information, not medical advice

A red, hot, painful breast lump with fever or feeling unwell needs prompt care — and spreading redness, a high fever with shivering, feeling very unwell, dizziness or confusion can signal sepsis: call 995 or go to A&E.

What it is

An abscess is a pocket of pus the body has walled off, which is why drainage is central to treatment. Lactational abscesses, the most common, arise from a blocked duct and milk stasis that become infected, often via bacteria entering through a cracked nipple. Non-lactational abscesses occur outside breastfeeding, including the subareolar type that forms behind the nipple and is strongly associated with smoking; diabetes or a weakened immune system also raise the risk.

Causes and risk factors

Common contributors include untreated or incompletely treated mastitis, a blocked milk duct and milk stasis, infrequent or interrupted feeds, poor latch or sudden weaning, and cracked or damaged nipples that let skin bacteria in. Smoking is a well-recognised risk for the non-lactational subareolar abscess because tobacco toxins damage the ducts behind the nipple, and diabetes, obesity, a weakened immune system, nipple piercing, a previous abscess or breast implants can also contribute.

Symptoms

There is usually a red, hot, swollen, very tender lump in the breast, often firm or fluid-filled, with skin over it that may look red or shiny (redness can be harder to see on darker skin, so look for warmth, swelling and pain). Fever, chills and feeling generally unwell or flu-like are common, and there may be pus discharge from the nipple or through the skin and swollen, tender lymph nodes in the armpit. It often follows a bout of mastitis whose symptoms did not settle.

Red flags

A red, hot, painful breast lump with fever or feeling unwell needs prompt medical assessment, and typically requires drainage rather than antibiotics alone. Signs the infection is spreading or becoming serious — redness spreading beyond the lump, rapidly worsening pain or swelling, a high fever with shivering or rigors, feeling very unwell, confusion, a fast heartbeat, or dizziness — can indicate sepsis and are an emergency: call 995 or go to A&E. Any breast lump that persists, is hard or fixed, or comes with skin dimpling or bloodstained nipple discharge should also be assessed, since a rare inflammatory breast cancer can mimic an infection that does not respond to treatment.

How it is assessed and treated

Assessment involves a clinical examination and an ultrasound, the key test to confirm a fluid collection (pus) rather than solid inflammation and to guide drainage, with aspiration of pus that can be sent for culture to identify the bacteria. In non-lactational or atypical cases, further imaging and sometimes a biopsy exclude an underlying cause. Drainage is the mainstay: needle aspiration under ultrasound guidance is often first-line and may be repeated over several visits, while a small incision and drainage is used for larger, thick-walled or recurrent abscesses. Antibiotics are given alongside drainage to treat the surrounding infection, but antibiotics alone usually will not cure an established abscess; this guide gives no doses. Addressing the cause matters — improving latch and feeding technique for lactational cases, and stopping smoking for subareolar or non-lactational abscesses, which also reduces recurrence — and recurrent subareolar abscesses sometimes need surgery to remove the affected duct.

Breastfeeding and recovery

If you are breastfeeding, it is generally safe and encouraged to continue breastfeeding or expressing from both breasts as advised, because keeping the milk flowing is part of treatment and aids recovery; a lactation consultant or doctor can help if feeding from the affected side is painful, in which case expressing that side while feeding from the other keeps it drained. Warm compresses, gentle massage toward the nipple, adequate rest and simple pain relief support recovery, and drinking enough fluids helps. It is worth seeking help early, since mastitis treated promptly — before an abscess forms — may settle with antibiotics alone, and stopping smoking is the single most useful step to prevent a non-lactational abscess returning. For breastfeeding mothers, preventing a recurrence largely comes down to keeping the breast well drained: feed or express regularly, make sure the baby is latching well (a lactation consultant can help), avoid tight bras or pressure on the breast, and treat any cracked nipple or early blocked duct promptly before it becomes infected.

When to see a doctor

See a doctor promptly if mastitis symptoms do not improve within about 24 hours of self-care or within about 48 hours of starting antibiotics, or if you develop a distinct painful lump, especially with fever. Seek urgent or emergency care (995 or A&E) for spreading redness, a high fever with rigors, or feeling very unwell, which can signal sepsis.

Related breast-health topics

• Fibrocystic breast changes
• Intraductal papilloma
• Galactorrhoea (milky discharge)
• Breast calcifications
• Mammary duct ectasia
• Phyllodes tumour
• Breast self-examination
• Inverted nipple
• Fat necrosis of the breast
• Breast cancer screening
• Breast surgeons in Singapore

Sources

• NHS — Mastitis: nhs.uk
• NHS — Skin abscess: nhs.uk
• Breast Cancer Foundation Singapore: bcf.org.sg
• SingHealth — Breast conditions: singhealth.com.sg