Boils and skin abscesses

Also called Furuncle, Carbuncle, Skin abscess

A collection of pus under the skin. Antibiotics alone rarely fix one; it needs draining, and squeezing it at home makes it worse.

What it is

A boil is an infection of a hair follicle that becomes a pocket of pus. An abscess is the same thing, larger and deeper. A carbuncle is a cluster of connected boils.

Most are caused by Staphylococcus aureus, including sometimes MRSA.

The governing principle is simple and often missed: **pus needs to come out.** Antibiotics penetrate a walled-off collection of pus poorly, so an established abscess usually needs incision and drainage, and antibiotics alone lead to repeated courses and a bigger abscess.

Squeezing or bursting one at home pushes infection deeper and into surrounding tissue. The one exception is a small boil that is pointing and discharging by itself, which can be helped with warm compresses.

Some sites are dangerous. Boils on the face, particularly around the nose and upper lip, and anything near the eye, spine or genitals, need medical assessment rather than home treatment.

Recurrent boils should prompt questions: diabetes, iron deficiency, immunosuppression, staph carriage in the nose, or, in the armpits and groin, hidradenitis suppurativa, which is frequently misdiagnosed as recurrent boils for years.

Signs you might notice

A red, painful, firm lump that grows over days and becomes softer and more painful, often with a visible yellow or white head.

Heat, swelling and throbbing pain.

Sometimes fever and feeling unwell.

Same-day assessment: fever with a spreading red area; a boil on the face, near the eye, near the spine or on the genitals; a very large or rapidly growing swelling; a boil in someone with diabetes or a weakened immune system; red streaks spreading from it; or a swelling that is not settling after a few days.

999 or A and E: rapidly spreading redness with severe pain out of proportion, skin turning dusky or black, or feeling very unwell, which may be a deep or necrotising infection. See sepsis.

How it can affect day-to-day life

The pain of an abscess is severe and is relieved almost immediately by drainage, which is why getting it done rather than waiting is worth it.

People often feel embarrassed and delay, particularly for boils in the groin, buttocks or under the breasts, and arrive with something much larger.

Repeated boils in the armpits, groin or under the breasts are the classic missed hidradenitis suppurativa. Two or more episodes in six months in those sites should change the diagnosis.

In care and shared living settings, staph spreads on towels, razors and bedding; separate laundering and not sharing personal items is the practical measure.

After drainage, the cavity is often packed and needs dressing changes for days, which is uncomfortable and requires district or practice nurse input.

Supporting someone well

Do not squeeze or burst it.

Warm compresses for 10 to 20 minutes several times a day can help a small boil come to a head and drain.

Keep it covered with a clean dressing while it is discharging, and wash hands afterwards.

Get it drained rather than accepting a second or third course of antibiotics.

Do not share towels, flannels or razors, and wash bedding and towels hot.

Get same-day help for the danger sites and danger signs above.

For recurrent boils, ask for a blood glucose test, an iron check, and consideration of nasal staph decolonisation.

For recurrent lumps in the armpits or groin, ask about hidradenitis suppurativa by name.

Where to get help

A pharmacist for early advice, including through Pharmacy First.

A GP practice or urgent treatment centre for drainage.

A and E for facial, spinal or rapidly spreading infection, or for signs of sepsis.

British Association of Dermatologists publish patient information on boils and staph infection.