Boil or furuncle is a skin disease caused by the infection of hair follicles, resulting in the localized accumulation of pus and dead tissue. Individual boils can cluster together and form an interconnected network of boils called carbuncles. In severe cases, boils may develop to form abscesses.
In some people, itching may develop before the lumps begin to develop. Boils are most often found on the back, stomach, underarms, shoulders, face, lip, eyes, nose, 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 area 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.
People with immune system disorders, diabetes, poor hygiene or malnutrition (Vitamin A or E deficiency) are particularly susceptible to getting boils; however, they also occur in healthy, hygienic individuals, due to over scratching a particular area of the skin.
The development of boils throughout the body is also a symptom of smallpox.
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"). Once the boil drains, the area should be washed with antibacterial soap and bandaged well. The maturing process may be accelerated by applying Ichthammol-based salve.
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 super bug known as Community-Associated Methicillin-Resistant Staphylococcus Aureus, or CA-MRSA. Appropriate drugs, active against MRSA, must be prescribed relatively soon after such a boil has started to form. MRSA tends to increase the speed of growth of the infection.
Magnesium sulphate (epsom salt) paste applied to the affected area can prevent the growth of bacteria and reduce boils by absorbing pus and drying up the lesion.