Acne in adults: causes and prescription treatments
Acne that arrives or persists in your twenties, thirties or later behaves differently from teenage acne: it sits along the jaw and chin, flares with the menstrual cycle, and reacts badly to the harsh products marketed for it. This page explains what causes adult acne, what works from a pharmacy, which treatments need a prescription, what scarring means for timing, and when to seek medical help.
What is different about adult acne?
Adult acne affects women more often than men and tends to concentrate on the lower face: jawline, chin and around the mouth, sometimes on the neck and upper back. Lesions are frequently deeper and more inflamed than teenage acne, with fewer blackheads and more tender nodules that last for weeks and leave marks.
It often fluctuates with the menstrual cycle, worsening in the week or so before a period. Skin is commonly drier and more easily irritated than adolescent skin, which is why the strong drying products aimed at teenagers frequently make adult acne worse by damaging the skin barrier and provoking more inflammation.
Two patterns deserve a mention. Acne that appears alongside irregular or absent periods, excess hair growth or difficulty conceiving can point to polycystic ovary syndrome, which is worth assessing. Small uniform bumps that appeared after starting a new medicine, a strong steroid cream or high-dose vitamin supplements may not be ordinary acne at all.
What actually causes it?
Four things combine. Sebaceous glands produce more oil under hormonal influence; cells lining the follicle stick together and block the opening; a skin bacterium, Cutibacterium acnes, multiplies in the blocked follicle; and the body mounts an inflammatory response that produces the red, painful lesions.
Hormonal fluctuation drives much of adult acne, which is why it varies through the cycle, changes in pregnancy and often flares after stopping hormonal contraception. Genetics strongly influence how severe it becomes. Stress does not cause acne but reliably makes existing acne worse, partly through hormones and partly through picking.
Diet has been studied extensively and the evidence is modest: high glycaemic load diets and, in some studies, skimmed milk show weak associations, while chocolate and greasy food have never been convincingly implicated. Acne is not caused by poor washing, and washing more often does not treat it. Cosmetics, hair products and prolonged occlusion from helmets, straps or face coverings can aggravate it locally.
What helps without a prescription?
Benzoyl peroxide is the most useful product available without a prescription: it reduces bacteria and unblocks follicles, and unlike antibiotics it does not select for resistance. Start with a low strength on alternate days, as it dries the skin and bleaches fabric and bedding. Azelaic acid suits sensitive skin and helps with the brown marks left behind, and salicylic acid preparations help mildly blocked skin.
The routine around it matters more than people expect. A gentle non-foaming cleanser twice daily, a light non-comedogenic moisturiser, and sun protection, particularly with treatments that make skin sun-sensitive. Scrubbing, alcohol-based toners and multiple active products at once damage the barrier and worsen inflammation.
Give any treatment eight to twelve weeks before judging it, and expect things to look slightly worse in the first fortnight. Do not squeeze deep lesions: it pushes inflammation deeper and is the single most avoidable cause of permanent scarring. Marks left after a spot heals are usually pigmentation rather than scars and fade slowly over months.
Which treatments need a prescription?
Topical retinoids such as adapalene and tretinoin are the core of prescribed treatment for most adult acne, because they address the blocked follicle rather than only the bacteria. They cause dryness and irritation initially and increase sensitivity to sunlight, and they are avoided in pregnancy and when planning pregnancy.
Topical antibiotics are used in combination with benzoyl peroxide or a retinoid, never alone, because using an antibiotic by itself encourages resistance. Oral antibiotics from the tetracycline group are used for moderate inflammatory acne for a limited period alongside a topical treatment, and they are not intended as an indefinite treatment. Tetracyclines are avoided in pregnancy and in young children.
For women whose acne is clearly hormonal, a doctor may discuss hormonal treatment options as part of the overall plan; that conversation belongs with a doctor who knows your history, your blood pressure and your risk factors. Isotretinoin, used for severe or scarring acne, is prescribed and supervised by a dermatology service under strict conditions, including a pregnancy prevention programme; we do not issue it.
Scarring: why timing matters
Scars form when inflammation destroys tissue in the deeper layer of the skin, and no treatment restores it fully afterwards. Procedures such as resurfacing and micro-needling can improve the appearance of established scars, but improvement is partial and it is expensive. Preventing scarring is far more effective than correcting it.
That is why deep, painful nodules, acne that is leaving marks or indentations, and acne that has not responded to a properly used treatment are reasons to escalate early rather than to try one more product. Referral to a dermatology service is appropriate for severe or scarring acne, and waiting a further year rarely improves the outcome.
Distinguish scars from marks. Flat brown or red marks left behind after a spot heals are post-inflammatory pigmentation, and they fade over months, faster with sun protection. Depressed or raised areas that alter the surface of the skin are scars. Picking and squeezing converts the first into the second more reliably than anything else.
When do I need medical help without delay?
Seek urgent medical care if acne worsens suddenly and dramatically with fever, joint pain, feeling generally unwell, or large painful ulcerating lesions. That pattern is uncommon but is treated as urgent, and it is not managed with over-the-counter products.
Call 112 or 999 for swelling of the face, lips or tongue, difficulty breathing, or a rapidly spreading rash with blistering or peeling of the skin or the inside of the mouth after starting any new medicine. Stop the medicine and get emergency help. Spreading redness with fever and severe pain around an inflamed area also needs emergency assessment.
Arrange an assessment promptly for acne that is scarring, deep painful nodules, acne appearing suddenly in adulthood with irregular periods or excess hair growth, or acne that has not improved after a properly used course of treatment. Speak to a doctor without delay about severe low mood or thoughts of self-harm, whether or not you are taking treatment for acne; Samaritans can be reached free on 116 123, and in an emergency call 112 or 999.
Acne treatment and pregnancy
Several standard acne treatments are not used in pregnancy. Oral and topical retinoids, tetracycline antibiotics and hormonal treatments are all avoided, and isotretinoin is subject to strict pregnancy prevention requirements because of its effects on a developing baby.
Options that are generally considered acceptable in pregnancy include some topical preparations such as azelaic acid, and a gentle skincare routine with sun protection. Because the choice depends on the stage of pregnancy and on what else you take, it should be made with a doctor, midwife or pharmacist rather than assumed from a product label.
If you are using an acne treatment and become pregnant or are planning to, ask before continuing rather than stopping everything in a panic; some products can be continued and others cannot. Acne commonly changes during pregnancy in both directions, improving for some women and worsening for others, and it frequently flares again in the months after delivery.
How long before an acne treatment works?
Give it eight to twelve weeks before judging, and expect skin to look slightly worse for the first couple of weeks. Changing product every fortnight is the commonest reason people conclude that nothing works.
Is adult acne caused by poor hygiene or diet?
No. Acne is driven by oil production, blocked follicles, bacteria and inflammation, and washing more often irritates skin without treating it. The dietary evidence is modest and points at high glycaemic load rather than at chocolate or greasy food.
Can I use antibiotics for acne long term?
Oral antibiotics for acne are prescribed for a limited period and always alongside a topical treatment such as benzoyl peroxide or a retinoid, to limit antibiotic resistance. Indefinite antibiotic use is not the intended plan, and treatment is reviewed rather than simply repeated.
Do you issue isotretinoin?
No. Isotretinoin for severe acne is prescribed and monitored by a dermatology service under strict conditions, including a pregnancy prevention programme and regular review. That supervision cannot be provided through an online questionnaire.
Will the marks left behind ever go?
Flat brown or red marks are pigmentation and usually fade over months, faster with daily sun protection. Indentations and raised areas are scars and do not resolve by themselves, which is why acne that is beginning to scar should be escalated early rather than treated for another year from a shelf.