Acne: Causes, Symptoms, and Treatment
Also known as: Acne vulgaris, Pimples, Breakouts
What Is Acne?
Acne is a chronic inflammatory skin condition affecting the hair follicles and oil glands. It shows up as pimples, blackheads, whiteheads, and sometimes deep nodules or cysts.
It typically appears at puberty due to hormonal changes, but it can persist into adulthood or show up for the first time as an adult. When that happens it is more common in women, often on the lower face and neck, and it tends to flare along with the menstrual cycle.
Acne is not caused by poor hygiene. Blackheads and pimples are not caused by dirt on the skin, and acne cannot be scrubbed off.
Symptoms
Acne lesions fall into two main categories.
Non-inflammatory lesions:
- Blackheads (open comedones)
- Whiteheads (closed comedones)
Inflammatory lesions:
- Papules: small red bumps
- Pustules: pimples with a white or yellow center (pus)
- Nodules: deep, painful lesions
- Cysts: pus-filled pockets, with a higher risk of scarring
Severity:
- Mild: a few blackheads and pimples
- Moderate: numerous papules and pustules
- Severe: nodules, cysts, scarring
Acne appears most often on the face, back, chest, and shoulders.
Causes and Risk Factors
Four biological mechanisms drive acne:
- Excess oil production (sebum)
- Clogged pores from dead skin cells
- Overgrowth of the bacteria Cutibacterium acnes
- Local inflammation
Aggravating factors:
- Hormones (puberty, menstrual cycle, pregnancy, PCOS)
- Stress
- A high-glycemic diet (sugar, white bread) and excess dairy
- Comedogenic cosmetics (oils, heavy creams)
- Pressure and friction (sports helmets, tight clothes, backpacks)
- Certain medications (corticosteroids, lithium, and medicines that contain hormones)
- Genetics: acne tends to run in families
Diagnosis
Diagnosis is clinical. A doctor or dermatologist examines the skin, identifies the type and severity of the lesions, and assesses the psychological impact.
Additional testing is rare, but a doctor may order:
- Hormone testing (testosterone, LH, FSH, DHEA) in women of childbearing age who also have excess hair growth or painful periods
Treatment
Treatment is gradual and tailored to severity. Most people see improvement within 4 to 6 weeks, and it can take 2 to 3 months or longer to see clearing, so it is worth sticking with a plan rather than switching products constantly.
Mild acne (topical treatment):
- Benzoyl peroxide, which reduces acne-causing bacteria and works best alongside another acne treatment
- Topical retinoids (adapalene, tretinoin), which unclog pores
- Azelaic acid, which also fades dark spots left after a breakout
Moderate acne (topical plus oral):
- Topical antibiotics (erythromycin, clindamycin) in combination
- Oral antibiotics (tetracyclines such as doxycycline), usually for three to four months and for the shortest time possible. They are never taken alone: pairing them with benzoyl peroxide or a topical retinoid keeps them working.
- Hormonal therapy in women (certain birth control pills, spironolactone)
Severe acne:
- Oral isotretinoin (Accutane and generics) is what dermatologists prescribe for nodular acne, the most severe type, when it hasn’t responded to other acne treatments. One course takes about four to five months. It requires strict monitoring: a fasting lipid profile and liver function tests before and during treatment, and an assessment for depression or mood changes at each visit. Because isotretinoin causes severe birth defects, it is available only through the iPLEDGE program, and patients who can become pregnant must use two forms of contraception for one month before, throughout, and for one month after treatment, with monthly pregnancy tests.
Additional treatments:
- Chemical peels
- Laser and light therapy. Blue, red, and blue plus red light devices can treat pimples, but they don’t work on blackheads, whiteheads, nodules, or cysts, and these treatments rarely clear acne on their own, so a dermatologist will usually pair them with another acne treatment.
Never pop pimples. It makes acne take longer to clear and raises your risk of permanent scarring.
Prevention and Tips
Daily habits:
- Cleanse your skin up to twice a day, and after sweating, with a gentle, non-abrasive cleanser applied with your fingertips
- Don’t over-strip the skin, since harsh products, astringents, and toners can make acne worse
- Moisturize with a non-comedogenic cream
- Don’t pick at pimples
- Remove makeup every night
- Wear a broad-spectrum sunscreen of SPF 30 or higher labeled non-comedogenic
- Keep your hands off your face, since touching it through the day can make acne flare
- Stay out of the sun and tanning beds. Tanning damages skin and can worsen acne, and some acne medicines make skin very sensitive to UV rays.
- Shampoo more often if your hair is oily, and keep it off your face
Diet:
- Limit added sugars and high-glycemic foods. A low-glycemic diet may reduce how much acne you have.
- Moderate milk if you notice a personal link. Studies have not found that yogurt or cheese leads to more breakouts.
Lifestyle:
- Stress management (exercise, meditation). Stress is associated with more severe acne.
When to Get Care
See a doctor or dermatologist if:
- Acne is widespread or painful
- You have nodules or cysts
- Acne doesn’t respond to basic treatment after 2 to 3 months
- Acne is affecting your mood or social life
- Scarring starts to appear
- You are an adult woman with persistent acne that doesn’t respond to usual treatment, along with irregular periods (possible PCOS)
FAQ
Does acne only affect teenagers?
No. Acne is most common in teens and young adults, and the AAD estimates that about 85% of people between the ages of 12 and 24 experience at least minor acne. But adults get it too: the AAD reports that adult acne continues to increase and affects up to 15% of women. About 20% to 40% of women with adult acne develop it for the first time as an adult.
How long before I see results from treatment?
Give any treatment at least 4 weeks. If it is working, you should notice some improvement in 4 to 6 weeks, and it can take two to three months or longer to see clearing. Patience is key.
Does diet play a role?
Yes, moderately. High-glycemic foods and cow’s milk have both been linked to acne, though more research is needed. Research has not shown that chocolate, nuts, or greasy foods cause acne, and keeping your skin clear requires more than a diet change.
Should I stop wearing makeup?
No, but choose non-comedogenic products and always remove makeup at night.
Does sun exposure improve acne?
No. Tanning damages your skin and can worsen acne, and some acne medicines make your skin very sensitive to UV rays from the sun and tanning beds. Stay out of the sun and tanning beds, and protect your skin when you are outside.
Can I pop a pimple?
Best to avoid it. Popping makes acne take longer to clear and increases the risk of a permanent scar.
Is isotretinoin (Accutane) dangerous?
Dermatologists prescribe it for severe nodular acne that hasn’t cleared with other treatments, and it requires close monitoring: blood tests for lipids and liver function, two forms of contraception for patients who can become pregnant (it causes severe birth defects), and an assessment for depression or mood changes at every visit.
Can acne come back after treatment?
Yes. Acne is a chronic condition, and breakouts can return. Most women with adult acne had acne as teens and keep getting breakouts as adults. If acne comes back after treatment, talk with your dermatologist about a longer-term plan.
Can acne scars fade?
Acne scars can fade, but they rarely go away completely on their own. For more noticeable scars, specific procedures exist: chemical peels, laser resurfacing, microneedling, and others such as fillers or scar surgery. The best way to avoid scars is to treat acne early, when you get your first breakouts.
Are stress and acne linked?
They are, but stress doesn’t cause acne on its own. It can make existing acne worse, and psychological stress is associated with more severe acne, probably by stimulating stress hormones. Managing stress fits into a broader treatment plan.
Sources
- American Academy of Dermatology (AAD), skin disease statistics: acne as the most common skin condition, 50 million Americans annually, 85% of people ages 12 to 24, up to 15% of women with adult acne
- American Academy of Dermatology (AAD), who gets acne and what causes it, adult acne in women (20% to 40% first develop it as adults)
- American Academy of Dermatology (AAD), acne and diet: low-glycemic diet, cow’s milk, yogurt and cheese
- American Academy of Dermatology (AAD), acne skin care tips: cleansing, harsh products, sunscreen, popping, sun and tanning, hands off the face, hair care
- American Academy of Dermatology (AAD), skin care habits that worsen acne: switching treatments, over-washing, sleeping in makeup
- American Academy of Dermatology (AAD), choosing a non-comedogenic moisturizer for acne-prone skin
- American Academy of Dermatology (AAD), wearing makeup with acne and removing it at night
- American Academy of Dermatology (AAD), treatment timeline: at least 4 weeks, improvement in 4 to 6 weeks, clearing in two to three months or longer
- American Academy of Dermatology (AAD), acne diagnosis and treatment: benzoyl peroxide, retinoids, azelaic acid, topical and oral antibiotics, hormonal therapy, isotretinoin for nodular acne, chemical peels
- American Academy of Dermatology (AAD), azelaic acid fading dark spots after a breakout
- American Academy of Dermatology (AAD), oral antibiotics for acne: three to four months, never taken alone
- American Academy of Dermatology (AAD), isotretinoin treatment: four to five month course, iPLEDGE REMS
- American Academy of Dermatology (AAD), acne scars rarely go away completely on their own, treating acne early prevents scars
- American Academy of Dermatology (AAD), procedures used to treat acne scars (chemical peels, laser resurfacing, microneedling, fillers, scar surgery)
- American Academy of Dermatology (AAD), how well lasers and light therapy treat acne
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), acne overview, who gets acne, aggravating factors (pressure and friction, stress, medications)
- StatPearls, Acne Vulgaris (NIH National Library of Medicine Bookshelf), adult female acne, stress and acne severity, hormone workup, hormonal therapy, scar procedures
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), PCOS symptoms (persistent acne, irregular periods)
- MedlinePlus, acne overview: who gets acne, dirty skin does not cause acne
- MedlinePlus, acne encyclopedia article: acne runs in families, hormonal triggers, clinical diagnosis, hormonal therapy, chocolate and greasy foods, popping pimples
- MedlinePlus, acne self-care: washing, non-comedogenic moisturizer, makeup, diet
- HealthyChildren.org (American Academy of Pediatrics), acne is not caused by dirt and cannot be scrubbed off
- DailyMed (U.S. National Library of Medicine), isotretinoin prescribing information: iPLEDGE REMS, two forms of contraception for one month before, during, and one month after, monthly pregnancy tests, fasting lipid and liver function monitoring, assessment for depression at each visit