Abscess

An abscess is a painful, swollen collection of pus within a tissue — most commonly the skin, but abscesses can form anywhere in the body. They usually result from a bacterial infection that the body has walled off. Skin abscesses often heal with drainage; deeper abscesses (in the lung, liver, brain, abdomen, or around teeth) can be serious and need specialist care.

Symptoms

Skin abscesses:

• Painful, swollen, red, warm lump
• A firm area that becomes soft and fluctuant as pus collects
• Sometimes a white or yellow head visible
• Surrounding redness, warmth
• Fever, feeling unwell, if the infection is spreading

Deeper abscesses can cause fever, weight loss, localised pain, and specific symptoms depending on the organ — cough and breathlessness for lung abscess, abdominal pain for liver or pelvic abscess, severe tooth pain and swelling for dental abscess.

Treatment

• Drainage — the main treatment. Small skin abscesses may drain on their own after warm compresses; larger ones need a doctor to make a small incision and drain the pus (incision and drainage)
• Do NOT squeeze or pop an abscess yourself — it can force infection deeper and spread it
• Antibiotics — used for large abscesses, cellulitis around the abscess, facial abscesses, abscesses in people with diabetes or weakened immunity, or when drainage alone isn't enough
• Deeper abscesses — need imaging (ultrasound, CT, MRI) to locate, and often drainage by a surgeon or interventional radiologist
• Dental abscesses — need dental treatment (drainage, sometimes root canal or extraction) plus antibiotics
• Underlying causes — diabetes, other infection sources — need to be addressed

When to see a doctor

• Any painful swelling larger than about 1 cm
• Fever with a skin infection
• Abscess on the face, hand, or genital area
• Spreading redness or streaks
• Abscess in someone with diabetes or weakened immunity
• Recurrent abscesses
• Severe pain out of proportion to appearance