What are boils and how are they treated?

What are boils and how are they treated?

The infections of skin and soft parts have always caused preoccupation and interest in humans.

These infections are a common cause of consult with the doctor, hospitalization, inability and therapy with antibiotics. The less serious are traditionally treated without the necessity of a surgical intervention, but they can become more severe and invasive, and even, put patients at risk of loss of soft tissues, amputation of a limb o death.

The skin is in direct contact with the ambient, which deposits on it dust, dirt and bacteria, among the ones the Staphylococcus aureus is found as a usual host. The biggest human organ (the skin or the Integumentary System, as it is also known), makes up the 16% of the body weight, it is sterile before the birth, but it is important know that since the first day of life the skin is contaminated with microorganisms which are going to be permanent hosts (usual flora of the skin), it is also important know that this flora can be present on the skin without be a cause of infectious processes.

The infections of skin and its structure are classified by the U.S.A Food and Drug Administration (FDA) as: uncomplicated and complicated, criterion that has been expanded and adopted by many in a kind of spontaneous consensus. The uncomplicated are the ones which respond to a simple cycle of antibiotics, a simple drainage or both; among these, the furunculosis is found, a disease with high frequency in the global population and which one we will talking about during all this article. 


A boil (or furuncle) is a painful, firm, deep and erythematous inflammatory nodule, which appears around the hair follicles and it gradually grows to form a fluctuant abscess. The causal agent (microorganism causing the infection) most know is the Staphylococcus aureus.

The injury consists of an inflammatory process with a bulging pustule or necrotic core through the one a hair emerges. After the rupture of a boil, the pus is expulsed at the same time as all the internal content of the inflammatory process, the wound begins to heal.

This a frequent affection and it is located in areas where polysebaceous follicles exist, because of that, they do not appear on the palms of the hands or on the soles of the feet, but in the areas of greatest friction: the neck, armpits, pubis area, buttocks, the external auditory canal and the hair follicles of nostrils. Though they can come out in any region of our body.

Predisposing factors

This infection can be acquire by any person but it is favored by irritation, friction, scratching and shave, especially in people suffering from:

 • Seborrheic dermatitis. 

 • Anemia.

 • Alcoholism. 

 • Mellitus Diabetes.

 • Hypogammaglobulinemia.

 • Malnutrition.

 • Obesity.

 • Treatment with corticosteroids and cytotoxic drugs.

 • Chronic renal failure.

 • Leukopenia (decrease of the white blood cells, usually indicating that the immune system is inhibited).

 • Others: Skin dirt, skin irritation, scratches of injuries, mental or physical fatigue, nutritional deficiency and diseases convalescence.

Clinical picture

Scrotal abscess

At the beginning, the boil is manifested as a firm nodule 1 to 2 cm, with erythema and pain.

In a matter of days it becomes fluctuating because the formation of an abscess under the lesion that, when draining, lets out its purulent content spontaneously. According to its location it is accompanied by a few general symptoms, though it can evolve with fever, pruritus (itching), general discomfort and headache. 

Between the 3rd and 4th day a yellow point appears.

After that, during the 5th and 6th day, it opens spontaneously in the form of an abscess.

About the 7th and 8th day the necrotic core is expulsed (dark central lesion, sometimes it is violaceous).

After the expulsion of the necrotic core, the cicatrization process starts.

When should you consult with a doctor?

You can generally take care of a boil by yourself if it is small and just one; but consult with your doctor if you have more than one or if a boil:

      • Is on your face or affects your vision.

      • Gets worse fast or it is extremely painful.

      • Causes fever.

      • Becomes bigger although the personal care.

      • Does not be cured in two weeks.

      • Appears again.

Should I take any antibiotic?

Yes, you should. The ideal will be realize a study that is denominated Culture and Antibiogram, in which one your doctor collects a sample of liquid from the lesion and through the study of this, it is determined what type of antibiotic will be more favorable for the patient, especially taking into account the characteristics of the germ in question. Nevertheless, in several occasions is recommended the use of systemic antibiotics, (empirical treatment), in general and most of cases is possible do it by the oral way, reserving the parenteral mode for when it is considered useful prevent complications or when these are presented.

The most recommended and used antibiotics are fist-generation cephalosporins (Cephalexin), the Amoxicillin, Macrolides, Tetracycline, Clindamycin, among others. Antibiotics with more potency can be used, as: third-generation cephalosporins (Ceftriaxone) and combinations with other antibacterial drugs by parenteral way in the complicated cases, risk factors present or multiple injuries. Always remember that the use of antibiotics most be indicated and prescribed by a health professional.


The small boils can generally be treated at home applying hot compresses to relieve the pain and favor the natural drainage; therefore, under no circumstances the classic conviction should be dismissed, for this and other superficial lesions, that cold is to diminish and hot is to soften and favor the collection and posterior drainage. The application of warm compresses to the boil speeds up liquefaction and it favors the spontaneous drainage.  

As a principal rule, a boil should never be squeezed. With this it is not favor the elimination of the necrotic core, and instead, the edema increases (inflammation), the lymphangitis appears and small septic thrombi can be detach which can provokes damage in all the body.

Remedies and measures that can help to the faster healing of the infection and to avoid it spreads.

      • Hot compresses. Apply a towel or a warm compress on the affected area several times a day, during 10 minutes each time. This helps to the boil´s break down and it drains faster.

      • Never squeeze a boil or cut it by yourself. This can spread the infection.

      • Prevent the contamination. After treat a boil, wash your hands well. Also, wash the clothes, the towels and the compress that have touched the infected area, especially if you have recurrent infections.

The application of unguents and ointments has not proved favorable results.

The early incision is not recommended, because it can accelerate the formation of the necrotic core, just when the formed necrotic core is very deep and the injury (pretty painful) takes time to open, a longitudinal incision can be practiced which goes through the furuncle in all its extension.

Technique of the incision and drainage


      • Hand washing, cleaning, disinfestation, wide delimitation of the area with sterile towels and using povidone-iodine.

Local anesthesia of the area

      • Application of a local anesthetic in the area without vasoconstrictors, this can increase the necrosis of the infected tissues. Its use is not just to eliminate the pain of the incision, but also to reduce the pain during the phase of debridement of the cavity. Remember that in these processes where the pus invades the area completely, full analgesia is unlikely to be achieved. It is superficially infiltrated the skin that covers the abscess and the perilesional deep tissues.

Furuncle incision

      • Fast puncture on the abscess surface in the area of greatest fluctuation with a scalpel blade #11, cutting the skin during the retreat movement of the blade in the direction of the skin tension lines of the area (go in puncturing and go out cutting). In case there is any doubt it can be done a puncture and 21G needle aspiration up to the outflow of purulent material; the incision should be wide to guarantee the right and full outflow of the pus. Though it is not usually necessary, a sample of pus will be taken for culture.

Furuncle drainage


      • It will be introduced in the cavity a Kocher forceps, opening it and closing it inside in all the directions with the objectives of break the partitions that have been formed and remove the remains of necrotic tissue and fibrin. In this way we achieve the output of the accumulated purulent material and that the inside of the cavity is left without remains of the infection.

Boil washing

      • Carry out abundant washing with saline serum which will be injected with a syringe applying a light pressure of the cavity up to the obtaining of clear wash liquid.

Introduce gauze wick

Extract gauze wick

      • With the help of the Kocher forceps we put a drainage in the cavity (gauze wick) soaked in iodopovidone solution leaving a part abroad for its extraction in the next cure, to avoid a superficial closing which could leave contaminated material inside it. In abscesses with a small size or very superficial it is not necessary.


The process finishes applying a bulky and sterile dressing.


The skin infections by the staphylococcus are the most common of all the bacterial infections in humans, so it is important recognize any type of infectious process lodged in our skin, to not waste time and start the treatment as soon as possible to avoid the development of complications that can greatly compromise our health.