A boil (furuncle) is a skin disease caused by the inflammation of hair follicles, resulting in the localized accumulation of pus and dead tissues. Individual boils can cluster together and form an interconnected network of boils called carbuncles. In severe cases, boils may develop to form abscesses.
The symptoms of boils are red, pus-filled lumps that are tender, warm, and/or painful. A yellow or white point at the center of the lump can be seen when the boil is ready to drain or discharge pus. In a severe infection, multiple boils may develop and the patient may experience fever and swollen lymph nodes. A recurring boil is called chronic furunculosis.
In some people, itching may develop before the lumps begin to develop. Boils are most often found on the back, underarms, shoulders, face, thighs and buttocks, but may be found elsewhere. Boils on the ear tend to be more painful, and can create shooting pain in the entire ear when touched.
Sometimes boils will emit an unpleasant smell, particularly when drained or when discharge is present, due to the presence of bacteria in the discharge.
Boils are generally caused by an infection of the hair follicles by Staphylococcus aureus or staph, a strain of bacteria that normally lives on the skin surface. It is thought that a tiny cut of the skin allows this bacterium to enter the follicles and cause an infection. This can happen during bathing or while using a razor.
People with immune system disorders, diabetes, poor hygiene or malnutrition (Vitamin A or E deficiency) are particularly susceptible to getting boils. However they may also occur in healthy, hygienic individuals.
Hidradenitis suppurativa causes frequent boils.
Boils in the armpits can sometimes be caused by anti-perspirant deodorants.
Most boils run their course within 4 to 10 days. For most people, self-care by applying a warm compress or soaking the boil in warm water can help alleviate the pain and hasten draining of the pus (colloquially referred to as "bringing the boil to a head"). Fire cupping can be utilised to facilitate this procedure. Once the boil drains, the area should be washed with antibacterial soap or antibacterial herbs (chickweed poultice) and bandaged well.
For recurring cases, sufferers may benefit from diet supplements of Vitamin A and E.
In serious cases, prescription oral antibiotics such as dicloxacillin (Dynapen) or cephalexin (Keflex), or topical antibiotics, are commonly used. For patients allergic to penicillin-based drugs, erythromycin (E-base, Erycin) may also be used.
However, some boils are caused by a superbug known as community-acquired Methicillin-resistant Staphylococcus aureus, or CA-MRSA. Bactrim or other sulfa drugs must be prescribed relatively soon after boil has started to form. MRSA tends to increase the speed of growth of the infection.
Magnesium sulfate paste applied to the affected area can prevent the growth of bacteria and reduce boils by absorbing pus and drying up the lesion.
For most cases, there are no serious complications and a full recovery is expected.