Acne
Created: 09.01.2025
Updated 20.04.2026
Approved by: Consultant Dermatologist, Dr James Denny
What is Acne?
Acne, medically known as acne vulgaris, is a common skin condition that affects the hair follicles and oil glands. It develops when pores become blocked with excess sebum, dead skin cells, and bacteria, leading to inflammation of the affected skin.
Acne most commonly appears on the face, chest, back, and shoulders, areas with a high concentration of oil glands. It is particularly prevalent during adolescence due to hormonal changes, but adult acne is increasingly common and may persist into the 30s, 40s, or beyond.
It is estimated that up to 80% of adolescents experience acne to some degree. While often associated with teenage years, acne can affect people of all ages and skin types.
What causes acne?
Acne is multifactorial. Several processes occur simultaneously:
- Increased oil production stimulated by hormones
- Blockage of hair follicles by dead skin cells
- Overgrowth of bacteria within the pore
- Inflammation
Hormonal fluctuations during puberty, menstrual cycles, pregnancy, or conditions such as polycystic ovary syndrome can contribute. Genetics also plays an important role.
Other factors that may worsen acne include:
- Stress
- Occlusive cosmetics
- Certain medications
- Friction from masks or helmets
- Harsh skincare products that cause skin irritation
Diet may influence acne in some individuals, particularly high glycaemic foods, although this varies between patients.
What are the symptoms of acne?
Acne symptoms vary depending on severity.
Non-inflammatory lesions include:
- Blackheads
- Whiteheads
Inflammatory lesions include:
- Red papules
- Pustules
- Tender nodules
- Cysts
In more severe cases, deep, painful lumps known as nodulocystic acne develop. This form carries a higher risk of permanent scarring if not treated promptly.
Acne may also lead to post-inflammatory hyperpigmentation and acne scars, particularly when lesions are deep or repeatedly picked.
How is acne diagnosed?
Dermatologists diagnose acne clinically by examining the skin and assessing lesion type, severity, distribution, and scarring risk.
Specialist review is important in:
- Persistent or severe acne
- Suspected hormonal causes
- Early scarring
- Cases not responding to initial treatment
Accurate assessment allows a tailored acne treatment plan that reduces long-term skin damage.
How do we treat acne?
Effective acne treatment depends on severity, type of lesions, skin sensitivity, and individual factors such as age and hormonal influences. Early intervention reduces the risk of acne scars.
Topical treatments
For mild to moderate acne, topical treatments are often first line. These may include:
- Topical retinoids to prevent blocked pores
- Benzoyl peroxide to reduce bacteria and inflammation
- Topical antibiotics, often combined with benzoyl peroxide to reduce resistance
- Azelaic acid, which helps reduce inflammation, pigmentation, and clogged pores
These treatments require consistent use and may initially cause mild skin irritation before improvement occurs.
Oral treatments
For moderate to severe acne, oral medications may be recommended.
These can include:
- Oral antibiotics for inflammatory acne
- Hormonal therapy in selected patients
- Oral isotretinoin for severe or treatment-resistant cases, particularly nodulocystic acne
Oral isotretinoin is highly effective but requires careful specialist supervision.
Acne scar management
Preventing scarring is a priority. Once acne is controlled, treatment options for acne scars may include:
- Laser resurfacing
- Microneedling
- Chemical peels
- Injectable treatments
Scar treatment is individualised based on scar type and skin characteristics.
Skincare advice
Patients aiming to treat acne should:
- Use gentle, non-comedogenic skincare products
- Avoid aggressive scrubbing
- Avoid picking or squeezing spots
- Apply treatments consistently as prescribed
Overuse of harsh products can worsen inflammation and increase skin irritation, delaying improvement.
Adult acne
Adult acne often presents differently from teenage acne. It may be concentrated on the lower face and jawline and can be linked to hormonal fluctuations. It may also coexist with sensitive skin.
Adult acne can have a significant psychological impact. Specialist dermatology assessment ensures appropriate management and long-term control.
What is the prognosis?
With appropriate treatment, most acne can be effectively controlled. Improvement typically takes several weeks, and consistent therapy is essential.
Early treatment reduces the risk of permanent scarring and pigmentation changes. Even severe acne can usually be brought under control with specialist-led care.
Although acne is a chronic inflammatory condition for some individuals, long-term management strategies allow most patients to maintain clear and healthy skin.
Frequently Asked Questions
What is the most effective acne treatment?
The most effective acne treatment depends on severity. Mild acne often responds to topical treatments such as retinoids, benzoyl peroxide, or azelaic acid. Moderate to severe acne, including nodulocystic acne, may require oral medication. A dermatologist can tailor treatment to reduce inflammation and prevent acne scars.
How long does it take to see improvement?
Most acne treatments take 6 to 12 weeks to show clear improvement. Some treatments may initially cause mild skin irritation before the skin begins to settle. Consistency is essential for long-term control.
Can acne cause permanent scars?
Yes. Deep or untreated acne, particularly nodules and cysts, can lead to permanent acne scars. Early specialist treatment significantly reduces the risk of scarring.
Is adult acne treated differently from teenage acne?
Adult acne often has a hormonal component and may require different treatment strategies, including hormonal therapy. It also tends to affect the lower face and jawline. Specialist assessment helps identify the most appropriate approach.
When should I see a dermatologist for acne?
You should seek specialist advice if your acne is severe, painful, leaving marks or scars, not improving with over-the-counter products, or affecting your confidence. Early intervention improves outcomes and helps prevent long-term skin damage.
