Overview of boils

Boils are furuncles. They result when the hair follicles in the skin become infected, presenting as a painful, red, firm, or sometimes soft and pus-filled lump.¹ Boils can occur on any body part but commonly occur in areas where sweat glands and hair follicles are present, such as the armpit, genital area, buttocks, thigh, or face. Although boils are more prevalent in adolescents and young adults, they can occur in any individual, regardless of their overall health.

Origin

Boils are caused by bacteria and the most common causative agent is Staphylococcus aureus.² These bacteria normally reside on the human skin and infections occur only when they penetrate the skin via cuts, abrasion, or wound.³

The bacteria infect the hair follicle and surrounding tissues and white blood cells are mobilised to combat infection. This results in inflammation of the hair follicles. Inflammation serves as a defence mechanism aimed at eliminating harmful organisms and initiating the process of tissue repair.

The infection eventually progresses to form a boil. Dead white blood cells, bacteria, and damaged tissue accumulate forming pus. When multiple nearby follicles become infected, they can merge and form a larger nodule called a carbuncle.

Risk factors 

People with weakened immune systems are more likely to develop boils. Other factors that would increase the likelihood of developing boils include:

• Contact with an infected individual
• Excess body weight
• Poor nutrition
• Existing skin injuries like atopic dermatitis 
• Poor personal hygiene

Clinical manifestations of boil 

The signs and symptoms exhibited by a person having a boil can be like other skin and soft tissue infections (SSTI). The clinical presentation of boil displays the classical signs of inflammation:

• Redness
• Swelling
• Pain
• Impaired function

Treatment options for boils

A boil might resolve independently without rupturing, but sometimes it needs to be opened and drained. Various interventions are available for the treatment of boils. It has been established that boils are caused by bacteria, an effective therapy needs to target the infectious agent. Therefore, antibiotics can be used as a viable option for its treatment.⁵

Home remedies and self-care

Warm compress

It involves a warm compress on the surface of the boil, helping to hasten the boil rupture. 

Proper hygiene

Good personal hygiene is crucial for managing boils. Regular bathing, hand washing, and using hand sanitiser after touching infected skin or items help prevent the spread of infection and support healing.

Pain relief measures

Over-the-counter pain medications, like paracetamol and ibuprofen, relieve the symptoms of pain associated with boils.

Role of antibiotics in treating boils

Antibiotics are drugs that either slow down the growth and reproduction of bacteria or eliminate them. In other words, antibiotics treat bacterial infections. Some antibiotics are specific and only target a particular bacterium. Others have a broad spectrum and can affect a range of bacteria, including those beneficial to the body.

When are antibiotics necessary?

Incision and drainage alone are typically effective for simple abscesses or boils. However, antibiotic therapy is recommended for abscesses in certain situations: severe or extensive infection, rapid progression with cellulitis, signs of systemic illness, underlying health conditions or weakened immune systems, extremes of age, and abscesses located in challenging drainage areas like the face, hand, or genitalia.⁶

In cases of recurrent furunculosis, the use of antibiotics may be mandatory. It is important to culture patient swabs to identify the specific bacteria that respond and effectively treat them with the right antibiotics.⁵

Types of antibiotics commonly used

Various types of antibiotics exist for the treatment of boils and are classified into two categories:

Topical antibiotics 

They are applied directly to the affected area and could be used alone or in combination with other interventions.⁷ Isolated and small furuncles can be treated using topical antibiotics such as fusidic acid or mupirocin, applied three times daily for seven to ten days.⁸

Systemic antibiotics 

This could include oral or intravenous antibiotics. Systemic antibiotics are considered adjunct therapy but are needed if abscesses exceed 5 cm in size or if cellulitis or fever is detected.⁹ They could be used with topical antibiotics. Systemic antibiotics are penicillin, cephalosporin, clindamycin, tetracycline, and trimethoprim‐sulphamethoxazole. 

How do antibiotics work? 

Antibiotics exhibit either a bactericidal (kill bacteria) or bacteriostatic (inhibit the growth of bacteria) activity depending on the class. They alter critical functions and components within the bacterial cell. They perform these actions by targeting specific sites on the cell:¹⁰ 

• Bacteria cell wall: Examples of antibiotics that target the cell wall are penicillin and cephalosporin
• DNA and RNA synthesis: an example of an antibiotic that targets DNA synthesis is fluoroquinolones
• Protein synthesis process: an example of an antibiotic that interferes with bacteria protein synthesis is tetracycline 

These bacterial targets are absent or have different structures in human cells, allowing antibiotics to specifically aim at bacteria without damaging our cells. Antibiotic action on the bacteria reduces the infection at the site, alleviates the symptoms, and promotes healing. 

You should use antibiotics when necessary and finish the course of therapy when it is prescribed to prevent the emergence of antibiotic resistant.¹¹

Potential side effects of antibiotic treatment

As with any medicine, antibiotics can cause side effects. Most antibiotics present no issues when correctly administered, and severe adverse effects are rare.

Common side effects

• Gastrointestinal issues: are mild and should not stop the patient from finishing the medications as they would resolve once the drug course is complete. However, if the side effects become severe and persistent, report to a doctor. They include:
  • Nausea and vomiting 
  • Diarrhoea
  • Mild stomach discomfort 
• Yeast infection
• Skin reactions, such as itching and rash
• Dizziness

Serious side effects 

They rarely occur but when they do, some can be life-threatening. 

Clostridiodes difficile infection: Most antibiotics, even broad-spectrum ones designed to combat various microorganisms, are ineffective against the bacteria Clostridiodes difficile. However, they do impact both harmful and beneficial bacteria in your gut. This disruption in the gut microbiome's balance enables organisms to grow and reduce other bacterial populations.

Allergic reactions. Antibiotics, particularly beta-lactam antibiotics (penicillin, cephalosporin), are among the most common triggers in adults.¹² Antibiotic-induced anaphylaxis is a systemic response caused by the rapid release of inflammatory mediators and other substances that affect the permeability of the vessels following the administration of the drug, affecting various organs. In patients with anaphylaxis, clinical manifestations may include urticaria and angioedema of the skin, airway obstruction, hypotension, and cardiac arrhythmias.¹³

Antibiotics resistance 

It is necessary to highlight the potential effect of antibiotic misuse or abuse to cause resistance. According to the World Health Organization (WHO), antimicrobial resistance (AMR) is one of the top threats to global public health and development. Antibiotic resistance occurs when the bacteria that cause diseases are unaffected by the antibiotics used to treat them.

Summary

Boils or furuncles are painful, hard, pus-filled lumps on the skin caused by infected hair follicles. The bacteria Staphylococcus aureus is the most common cause. Boils can occur in any individual regardless of their health status. Individuals having weak immune system are more predisposed to them.

Small boils may resolve with simple home remedies, but large and complex boils are treated with antibiotics. Antibiotics disrupt the growth of the bacteria thereby reducing infection, alleviating symptoms, and promoting healing. 

As with all drugs, there are always potential side effects. Diarrhea, nausea, and vomiting are common side effects associated with antibiotics. Severe side effects, like anaphylaxis, rarely occur and are life-threatening. The likelihood of experiencing these side effects varies among individuals.

Maintain good personal hygiene. Seek medical advice especially in cases of recurrent boils so they can assess and recommend the appropriate treatment intervention. Avoid the indiscriminate use of antibiotics and use prescribed antibiotics appropriately.