Adult acne: why it happens, who gets it and what treatments work

Acne is a common skin condition causing spots that range from mild to severe. The NHS says it usually affects the face, chest and back, and describes whiteheads, blackheads, papules, pustules and nodules or cysts, the last being larger lumps under the skin that may join together and can be painful.

Adult acne is simply acne that persists beyond the teenage years or starts later. BAD says acne can develop for the first time in people in their late twenties and beyond. Many adults, particularly women, find that spots concentrate around the jawline, chin and neck, and that flares coincide with their periods, though this pattern is not universal.

The NHS says acne can happen when hair follicles become blocked with excess oil and dead skin cells, and bacteria can grow in the blocked follicles and cause inflammation and pus. It lists changes in hormone levels, such as during puberty, periods, menopause and pregnancy, conditions such as polyendocrine metabolic ovarian syndrome (PMOS, which used to be called polycystic ovary syndrome) and rosacea, taking certain medicines and using products on the skin or hair that make the skin greasy.

BAD explains that the oil-producing sebaceous glands are particularly sensitive to hormones in acne, even when the hormones are at normal levels, and that sometimes acne can be caused or made worse by excess hormones, as in PCOS, by certain hormonal contraceptive preparations or high-dose steroids, and by anabolic steroids taken by bodybuilders. It adds that a combination of genetic, hormonal and lifestyle factors such as stress, skincare products and smoking probably act together, and that there is not enough evidence to support specific diets for treating acne, although a healthy, balanced diet is advisable.

Acne that starts in adulthood with irregular periods, excessive hair growth, hair thinning or difficulty getting pregnant may point to a hormonal condition. The NHS lists PMOS symptoms as irregular periods, excessive hair growth, weight gain or difficulty losing weight, difficulty getting pregnant, oily skin and acne, and dark patches of skin on the neck or armpits.

Sudden severe acne, particularly with a deepening voice, rapid hair growth or other changes, needs prompt medical review. Review your medicines and any supplements, gym products or hormones you take, because some can trigger acne.

The NHS advises washing the skin twice a day with a gentle cleanser, removing make-up at the end of the day, using non-comedogenic skincare and make-up, trying products containing salicylic acid or benzoyl peroxide with advice from a pharmacist, and wearing loose, breathable clothing if you have acne on the body. It advises against picking or squeezing spots and against scrubbing the skin.

A pharmacist can recommend treatments to put on the skin and supplements that come as tablets such as zinc, niacinamide and vitamin A, according to the NHS. Give any new product several weeks before judging it, and avoid mixing several strong products at once, because irritation can be mistaken for worsening acne.

The NHS says a GP may offer treatments you can only get with a prescription or refer you to a dermatologist, and BAD says these are usually used in stages from topical treatments for mild to moderate acne through to tablets for more severe disease.

BAD says acne can leave scars or marks on the skin, particularly with nodules and cysts, and that scars may be raised and lumpy (hypertrophic or keloid) or indented (pitted or atrophic). It says treatments can be very effective, preventing the formation of new spots and reducing scarring. That is why early treatment of deep acne is recommended rather than waiting for it to burn out.

Scars that remain after the acne is controlled can be treated by dermatology or cosmetic services. This is usually deferred until acne is inactive and, for people who have taken isotretinoin, for a period afterwards.

The NHS says that having acne can affect mental health, causing anxiety, depression and low self-esteem, and that you should see a GP if it is affecting your mental health. Adults with acne often feel embarrassed because they expected it to be over. This is a recognised reason to seek treatment in its own right.

If low mood is persistent or you have thoughts of harming yourself, speak to a GP or call NHS 111. This is particularly important when taking isotretinoin, where mood is monitored.

On the NHS the first step is a pharmacist or GP, who can prescribe topical and oral treatments and refer to a dermatologist if acne is severe, scarring or has not responded. Isotretinoin is prescribed under specialist supervision.

Private dermatologists and aesthetic clinics offer quicker appointments, and treatments such as chemical peels or light therapies. Check that a doctor on the GMC specialist register (or equivalent) is supervising medical treatments, and that prescription medicines are properly monitored.