What are the aims of this leaflet?
This leaflet has been written to help you understand more about boils (furuncles). It explains what they are, what causes them, what can be done about them, and where you can find out more about them.
What are boils?
A boil, or furuncle, is an abscess (infection) of the skin or in the deep part hair follicles. The infection is usually caused by bacteria called Staphylococcus aureus (S. aureus). Occasionally the infection may spread into the surrounding tissues (cellulitis) and can cause fever and a feeling of being unwell. When several boils form close together and join, this is known as a carbuncle. Sometimes rarer types of S. aureus: Methicillin resistant Staphylococcus aureus (MRSA) and Panton-Valentine leukocidin (PVL), can cause boils. PVL may cause larger and more painful boils (see Patient Information Leaflet on PVL Staphylococcus Aureus (PVL-SA) skin infection).
The bacteria causing the boil can occasionally spread from one part of the body to another and from one person to another by skin-to-skin contact and from clothing and towels which have been contaminated with pus from the boil. This is especially true when boils are caused by the PVL strain of S. aureus bacteria. Boils are common in teenagers and can affect boys more often than girls. Sufferers of boils do not usually have a problem with their immune system, but boils can be more severe in patients with a suppressed immune system. Boils are more common in patients with diabetes and those who are overweight.
What do boils look like?
Boils may be single or multiple. A boil often starts as an itchy or tender spot that grows over a few days into a large firm red lump which becomes very painful. Boils often develop around the neck, face, back, breasts, thighs and buttocks. Boils inside the nose or ear, or under tight clothing can be particularly uncomfortable.
As the boil continues to grow the centre eventually softens and becomes filled with pus. The pus may then burst through the surface of the skin or it may settle gradually without bursting.
A healed boil tends to leave a red mark, which slowly fades, but can leave a scar.
How are boils diagnosed?
Boils are usually easy to diagnose by their appearance. If a boil contains pus, the doctor may use a sterilised needle to take a sample of the pus which can then be swabbed and sent to the laboratory to check which bacteria are causing the boil and which antibiotic treatment may be appropriate.
Can boils be cured?
Yes, infections get better with treatment.
S. aureus survives well in moist areas such as the nostrils, armpits, buttocks and groin. Some people carry S. aureus at these sites on a long-term basis and are referred to as 'carriers'. This is not usually a problem, however, if repeated boils occur, it is wise to treat these areas (see below).
How can boils be treated?
A warm salt-water soaked dressing applied to the boil for 10-20 minutes several times a day may encourage the drainage of pus to drain which then helps reduce the pain. A single boil usually gets better naturally, especially if the pus it contains discharges spontaneously. However, occasionally the doctor may release the pus by cutting carefully into the boil (lancing) using sterile instruments. An antibacterial cream, ointment or solution can be used around the boil to stop other boils from appearing nearby. Often an antibiotic is given by mouth, to help clear the infection.
How do I stop the bacteria from spreading?
- The doctor may prescribe a topical treatment such as an antibacterial soap, solution or cream to wash with. Sometimes an antibacterial nasal ointment is recommended be applied into each nostril for 5-7 days. Family members may also have to use these treatments if they are found to be carriers.
- It often helps for family members to use antibacterial washes if they are in close contact and share the same bed.
- Change towels every day and do not share them with anybody else.
- Wash bed sheets at least weekly or at once if pus is discharged.
- Keep the house clean, especially the sink, shower or bath.
- Pus contains bacteria so avoid getting the pus from the boil onto other areas of the skin. If pus is discharged, wash the area around carefully with an antibacterial product and also wash the hands to avoid spreading the infection.
You should seek medical advice if you are not sure of the diagnosis or if you feel unwell. You should also see the doctor if the problem persists or if you have recurring boils.
Self care (What can I do?)
- Follow the measures outlined above to reduce the spread of boils.
- Bath or shower daily, and keep your hands and nails clean. Avoid picking any sores.
- Being overweight encourages boils, as the bacteria survive in folds of the skin; in such cases weight loss may help prevent recurrence.
- If the boils are on exposed skin, avoid close contact with others and contact sports, such as rugby and judo, until the boils have cleared to reduce the risk of passing the infection onto others.
- Do not visit a swimming pool or a gym until the boils have cleared up.
Where can I get more information?
Web links to detailed leaflets:
For details of source materials used please contact the Clinical Standards Unit (firstname.lastname@example.org).
This leaflet aims to provide accurate information about the subject and is a consensus of the views held by representatives of the British Association of Dermatologists: individual patient circumstances may differ, which might alter both the advice and course of therapy given to you by your doctor.
This leaflet has been assessed for readability by the British Association of Dermatologists’ Patient Information Lay Review Panel
BRITISH ASSOCIATION OF DERMATOLOGISTS
PATIENT INFORMATION LEAFLET
PRODUCED JUNE 2007
UPDATED MAY 2010, MAY 2013, SEPTEMBER 2016, JANUARY 2020
REVIEW DATE JANUARY 2023