Acne: Causes, Triggers, and Evidence-Based Management

Understanding acne

Acne is one of the most common skin conditions worldwide, affecting the majority of people at some point, most often during adolescence but frequently persisting or emerging in adulthood too. While often dismissed as a purely cosmetic issue, acne can cause genuine physical discomfort and has a well-documented impact on self-esteem and mental wellbeing.

Effective acne management depends on understanding its underlying causes and matching treatment intensity to severity — using the wrong approach, or waiting too long to seek treatment for more severe acne, can increase the risk of permanent scarring.

Common misconceptions

"Acne is caused by poor hygiene." Acne is driven by hormones, genetics, and follicle blockage — not dirtiness. Over-washing can actually worsen it by irritating the skin.
"Only teenagers get acne." Adult acne is common, particularly in women, and can be linked to hormonal fluctuations, PCOS, or stress.
"Popping spots helps them heal faster." Picking or squeezing acne lesions increases the risk of scarring and can worsen inflammation.
"Sun exposure clears acne." Tanning may temporarily mask redness but does not treat acne and increases long-term skin damage risk.

When to seek medical care

Seek prompt medical review if you have:

Painful, deep cystic or nodular acne that is rapidly worsening
Signs of skin infection (spreading redness, warmth, fever)
Severe emotional distress or impact on mental health related to your skin

Book a GP or dermatology appointment if:

Over-the-counter treatments haven't improved your acne after 2–3 months of consistent use
You are developing scarring or dark marks
Acne appears alongside other symptoms like irregular periods or excess hair growth (possible PCOS)

Routine self-care is appropriate for:

Mild, occasional breakouts managed well with basic skincare and non-prescription treatments

Why acne develops

Acne occurs when hair follicles become blocked with oil (sebum) and dead skin cells, creating an environment where bacteria (C. acnes) can proliferate and cause inflammation.

Hormonal changes — androgens increase sebum production (puberty, PCOS, menstrual cycle)
Genetics — family history is a major risk factor
Certain medications — steroids, lithium, some contraceptives
Comedogenic products — some skincare or makeup that blocks pores

Acne can sometimes be confused with other inflammatory skin conditions. If you are unsure, see our comparison of eczema vs psoriasis to understand the differences.

Evidence-based treatments

Mild acne: benzoyl peroxide, salicylic acid, topical retinoids
Moderate acne: topical antibiotics (with benzoyl peroxide to reduce resistance)
Hormonal acne: combined oral contraceptive pill may help in women
Severe acne: oral isotretinoin (under specialist supervision)
Diet: high glycaemic index foods and dairy may worsen acne in some people

For guidance on monitoring any skin change over time, see our checklist on what to track with skin concerns.

Related Skin Guides

Explore related skin guides to better understand common skin changes, warning signs, and when further review may be needed.

Skin concerns are often easier to understand when looked at alongside pattern, appearance, and change over time. You can explore related guides above or use Healio360's skin assessment tool for more structured guidance.