Severe Acne: Types, Causes, and Suitable Treatments

Nodules

Nodules are deep inflammatory masses measuring more than 5 mm in diameter, located in the dermis (the middle layer of the skin). These often painful lesions do not always show visible redness on the surface. Nodules may rupture spontaneously, outwardly or deeper into the dermis, increasing inflammation and the likelihood of permanent scarring.

Cysts

Cysts, or pseudo-cysts, are deep lesions enclosed by a rigid membrane that prevents their internal fluid from draining. Their size may vary, and they do not resolve spontaneously, sometimes persisting indefinitely. They are most commonly found on the back and shoulders.

Scars

Scars from severe acne can be pitted (atrophic), raised (hypertrophic), or thick and swollen (keloid). Atrophic scars appear in various forms:

• Ice-pick scars: deep and narrow.
• Rolling scars: depressions with sloping edges.
• Boxcar scars (“U-shaped”): round or oval with sharp, defined borders.

Hypertrophic scars are firm, pink, and raised, remaining within the original area of injury. Keloid scars—often red or purple—grow beyond the boundaries of the original lesion, more frequently affecting the torso and individuals with darker skin tones.

In addition to scarring, inflammatory lesions may cause post-inflammatory hyperpigmentation (darker patches appearing after inflammation), especially in people with darker skin. They may also lead to post-inflammatory erythema (redness) in lighter skin types.

Abscesses

Abscesses are pockets of pus that develop in the deeper layers of the skin (dermis or hypodermis) following the rupture of infected follicles. These infectious lesions are often painful and increase the risk of scarring. Surgical drainage may be necessary in some cases. 

What are the types of severe acne?

Severe acne encompasses several rare, severe forms of the condition, defined by deep, inflammatory and often painful lesions.

Nodulocystic acne¹ ² ³

Nodulocystic acne is a chronic, severe form of acne, predominantly affecting adolescents and young adults—most commonly males. It presents with large comedones that become inflamed to form firm, painful nodules and cysts, which may persist indefinitely and leave scars. Nodular acne frequently involves the shoulders, back, and torso. Deep lesions, especially if manipulated or improperly treated, increase the risk of permanent scarring.

Acne conglobata¹ ² ⁴

Acne conglobata is a rare and particularly severe variant of nodulocystic acne. It is characterised by clusters of interconnected inflammatory lesions merging under the skin to form a network of comedones, papules, pustules, nodules, cysts, and abscesses. These lesions can fuse into large, painful, and sometimes foul-smelling inflammatory masses. Acne conglobata mainly affects young men on the face, shoulders, back, chest, buttocks, and sometimes the thighs. It resolves slowly, often leaving numerous scars.

Acne fulminans¹ ² ⁵

Acne fulminans is a rare and extremely severe form of inflammatory acne that primarily affects adolescent males with a pre-existing moderate to severe acne.

It is a sudden outbreak of painful, haemorrhagic papules, pustules, and nodules. These lesions often ulcerate and become covered with crusts, leading to significant scarring. The most commonly affected areas include the face, upper chest, back, and shoulders, though lesions may sometimes spread to the thighs.

This condition can be associated with systemic symptoms such as high fever (> 39°C), joint pain, severe fatigue, and weight loss. Blood tests may show abnormalities (reduced red blood cell count, increased white blood cell count, among others).

Possible triggering factors include treatment with isotretinoin, the use of anabolic steroids or testosterone, hormonal imbalances, and genetic predisposition.

Causes and aggravating factors of severe acne¹ ² ³

Acne is influenced by both internal and external factors that worsen inflammation.

Hormonal factors

Hormonal imbalances play a central role in acne development. During adolescence, androgens stimulate the sebaceous glands, increasing sebum production and clogging pores. In adult women, hormonal fluctuations—particularly before menstruation—often exacerbate acne flare-ups. Some conditions, such as polycystic ovary syndrome (PCOS) or adrenal gland disorders, can also aggravate the problem.

The role of genetics

Family history is a significant risk factor for severe acne. An inherited predisposition may present as increased sebum production and heightened sensitivity of the pilosebaceous follicles, intensifying lesion severity and increasing the likelihood of scarring.

Lifestyle, stress, and diet

A diet rich in high-glycaemic index foods (simple sugars) or dairy products may stimulate sebaceous gland activity and inflammation. Protein supplements derived from cow’s milk, such as whey used in bodybuilding, add further risk. Conversely, a balanced diet may enhance skin health by emphasising fruits, vegetables, and low-glycaemic index foods.

Stress is a well-established aggravating factor, increasing sebum production and promoting behaviours like picking at lesions. Together, these factors can heighten inflammation and scarring risk. Smoking also alters sebum composition and can contribute to non-inflammatory acne lesions.

Environmental factors and cosmetics

Using comedogenic skincare and cosmetic products can worsen acne. Seasonal changes also play a role: some people note an improvement in acne during summer, while others experience flare-ups after sun exposure. Lesions often worsen in autumn.

Medications and specialised treatments

Certain medications—such as corticosteroids, vitamin B12, lithium, or contraceptives containing androgenic progestins—can trigger or worsen acne. Additional risk factors include anabolic steroids used in bodybuilding and haemodialysis.

Which treatments are available for severe or complex acne?

Treatment principles¹ ² ³

Treating severe acne or very severe forms requires thorough, carefully managed approaches, often favouring systemic therapies due to the limited effectiveness of topical treatments alone. Oral isotretinoin is suggested if a well-conducted systemic treatment fails. This medication necessitates strict monitoring because of potential side effects. In women of childbearing age, effective contraception is mandatory owing to the high risk of severe congenital disabilities (teratogenic risk). Monthly pregnancy tests are required. For all patients, close clinical and psychological follow-up is maintained throughout treatment.

Special cases

• Treating acne conglobata⁴
  Managing acne conglobata calls for a comprehensive strategy. Oral isotretinoin is the cornerstone therapy, sometimes combined with oral prednisone (a corticosteroid) to control initial inflammatory flare-ups or systemic symptoms. Localised procedures, such as aspiration or intralesional corticosteroid injections, may also be necessary.
   
• Treating acne fulminans⁵
  Managing acne fulminans relies on a systemic approach tailored to the severity of symptoms and any systemic involvement. First-line treatment usually involves oral corticosteroids alone to reduce inflammation rapidly. Depending on the cause of acne fulminans, a systemic agent such as isotretinoin can be introduced gradually after a few weeks of corticosteroid therapy. In certain situations, immunosuppressants or biologic therapies may be necessary.

Local dermatological treatments and surgical interventions can also help alleviate inflammation, promote lesion healing, or address residual scarring.

How can severe acne be prevented?¹ ² ⁶

Preventing severe acne involves a combination of appropriate skincare, good hygiene practices, and specific lifestyle adjustments.

Hygiene and skincare

Cleanse your face morning and evening using a gentle, non-irritating cleanser specifically formulated for acne-prone skin. Wash again after intense physical activity that causes heavy sweating. Keep your skin well-hydrated with a non-comedogenic moisturiser to maintain the hydrolipidic balance and counteract the drying effects of some treatments.

Choose non-irritating products, avoiding harsh scrubs or masks containing alcohol. Any skincare or cosmetic products should be non-comedogenic and suited to oily or combination skin. Remove make-up thoroughly each evening to prevent clogging pores. If you have greasy hair, wash it regularly—especially if it comes into contact with your forehead—to reduce breakouts.

Environmental factors and lifestyle habits

Avoid picking or frequently touching your lesions, as this can increase the risk of scarring. Protect your skin from UV rays by using a non-comedogenic sunscreen designed for acne-prone skin, particularly if you are on photosensitising treatments such as retinoids or cyclines.

Follow a balanced diet rich in fruits and vegetables, limiting simple sugars and dairy products if you observe a link between these and flare-ups. Quitting smoking may also improve skin health.

Lastly, manage stress through relaxation techniques like yoga or meditation.

What are the psychological impacts of severe acne?² ⁴ ⁷

Severe acne, especially when it affects the face, can have profound psychological repercussions and reduce the overall quality of life.

Effects on self-image and social relationships

People with severe acne may develop a negative perception of their appearance, leading to a marked drop in self-esteem. This distress is often worsened by social stigma and judgments about visible lesions. Withdrawing from social interactions—or even becoming isolated—is common, lowering the quality of life.

Mental health risks

Severe acne is also linked to increased levels of anxiety and depression, which can persist even when skin lesions improve. Adolescents and young adults are particularly vulnerable, given the pressures surrounding appearance and social acceptance.

Support and assistance

A comprehensive approach is essential to mitigate these psychological impacts. This includes not only effective dermatological treatments but also appropriate psychological support. In cases of severe emotional distress, specialised psychological or psychiatric care may be needed.