Acne - Causes, Symptoms, Diagnosis, Treatment & When to Seek Medical Help

Introduction
Acne is a common skin condition that affects most people at some point. It causes spots, oily skin and sometimes skin that feels hot or painful to touch. Acne most often affects the face, but it can also occur on the back and chest.

Causes

Acne happens when tiny holes in the skin called hair follicles become blocked with oil and dead skin cells. Sebaceous glands attached to follicles produce an oily substance called sebum. When too much sebum is made, it mixes with dead skin cells and forms a plug in the follicle.

Blocked follicles can become infected by harmless skin bacteria, leading to inflammation and spots. Hormonal changes, especially during puberty, increase sebum production, which is why acne is so common in teens. Acne also runs in families, and hormonal fluctuations in women (such as during menstrual cycles or pregnancy) can trigger breakouts.

There’s no strong evidence that diet, poor hygiene or sexual activity directly causes acne.

Types of Spots

There are six main types of spot associated with acne:

• Blackheads – small dark bumps from open blocked follicles

• Whiteheads – closed blocked follicles that don’t empty if squeezed

• Papules – small red tender bumps

• Pustules – red bumps with a white or yellow centre

• Nodules – larger, deeper hard lumps that can be painful

• Cysts – large pus-filled lumps that carry the highest risk of scarring

Diagnosis

A GP can usually diagnose acne by examining the affected areas (face, chest or back) and noting the types and number of spots. Severity is classified as mild, moderate or severe depending on the number, size and depth of spots.

In women, new or worsening acne later in life may warrant investigation for hormonal conditions such as polycystic ovary syndrome (PCOS).

Treatment

Acne treatment depends on its severity and can take several months before improvement is noticeable.

Self-Help and Over-The-Counter Care

For mild acne, try these first:

• Wash the affected skin no more than twice a day with a mild cleanser

• Avoid trying to “clean out” or squeeze spots

• Avoid heavy or oil-based cosmetics — use non-comedogenic products

• Remove makeup completely before bed

• Keep hair clean and avoid letting it fall on the face

Several creams, lotions and gels containing benzoyl peroxide are available from pharmacies and can help manage spots.

Medical Treatments from a GP

You should see a GP if over-the-counter treatments haven’t helped, or you have more widespread, painful, or worsening acne. Prescription options include:

• Topical retinoids – help prevent blocked follicles

• Topical antibiotics – reduce bacteria and inflammation

• Azelaic acid – reduces bacteria and exfoliates skin

• Oral antibiotics – for more widespread or inflammatory acne

• Combined contraceptive pill – can help in women with hormonal acne

• Isotretinoin – a stronger oral medicine for severe acne that hasn’t responded to other treatments

These treatments often take 6–12 weeks or longer to show improvement.

Complications

• Scarring: occurs especially with deeper nodules or cysts

• Hyperpigmentation: darker marks can remain after spots heal

• Psychological effects: acne can affect self-esteem and mental well-being

Avoid picking or squeezing spots as this increases the risk of scarring.

When to Seek Medical Help

See a GP if:

• Acne is moderate or severe

• You have lots of papules, pustules, nodules or cysts

• Acne is causing emotional or psychological distress

• Over-the-counter products haven’t helped after several weeks

Urgent medical advice may be needed if acne is associated with rapidly worsening redness, swelling, pain or signs of infection.

Complications and Long-Term Effects

Acne Scarring

Acne scarring can develop when deeper spots (especially nodules or cysts) rupture and damage the surrounding skin. Avoid squeezing spots to reduce this risk.

Impact on Mental Health

Acne can affect emotional well-being, leading to anxiety, low mood or reduced self-esteem. If you’re struggling emotionally, speak to your GP.

For more information, please visit:

• Acne overview and self-help: https://www.nhs.uk/conditions/acne/
• Diagnosis and severity: https://www.nhs.uk/conditions/acne/diagnosis/
• Treatment options: https://www.nhs.uk/conditions/acne/treatment/