Acne is a common skin condition that affects most people at some point. It causes spots, oily skin and sometimes skin that's hot or painful to touch.

Acne most commonly develops on the:

• face – this affects almost everyone with acne
• back – this affects more than half of people with acne
• chest – this affects about 15% of people with acne

Types of spots

There are six main types of spot caused by acne:

• blackheads – small black or yellowish bumps that develop on the skin; they're not filled with dirt, but are black because the inner lining of the hair follicle produces pigmentation (colouring)
• whiteheads – have a similar appearance to blackheads, but may be firmer and won't empty when squeezed
• papules – small red bumps that may feel tender or sore
• pustules – similar to papules, but have a white tip in the centre, caused by a build-up of pus
• nodules – large hard lumps that build up beneath the surface of the skin and can be painful
• cysts – the most severe type of spot caused by acne; they're large pus-filled lumps that look similar to boils and carry the greatest risk of causing permanent scarring

What can I do if I have acne?

The self-help techniques below may be useful:

• Don't wash affected areas of skin more than twice a day. Frequent washing can irritate the skin and make symptoms worse.
• Wash the affected area with a mild soap or cleanser and lukewarm water. Very hot or cold water can make acne worse.
• Don't try to "clean out" blackheads or squeeze spots. This can make them worse and cause permanent scarring.
• Avoid using too much make-up and cosmetics. Use water-based products that are described as non-comedogenic (this means the product is less likely to block the pores in your skin).
• Completely remove make-up before going to bed.
• If dry skin is a problem, use a fragrance-free, water-based emollient.
• Regular exercise can't improve your acne, but it can boost your mood and improve your self-esteem. Shower as soon as possible once you finish exercising, as sweat can irritate your acne.
• Wash your hair regularly and try to avoid letting your hair fall across your face.

Although acne can't be cured, it can be controlled with treatment. Several creams, lotions and gels for treating spots are available at pharmacies.

If you develop acne, it's a good idea to speak to your pharmacist for advice. Products containing a low concentration of benzoyl peroxide may be recommended – but be careful, as this can bleach clothing.

If your acne is severe or appears on your chest and back, it may need to be treated with antibiotics or stronger creams that are only available on prescription.

When to seek medical advice

Even mild cases of acne can cause distress. If your acne is making you feel very unhappy or you can't control your spots with over-the-counter medication, see your GP.

Also see your GP if you develop nodules or cysts, as they need to be treated properly to avoid scarring. Try to resist the temptation to pick or squeeze the spots, as this can lead to permanent scarring.

Treatments can take up to three months to work, so don't expect results overnight. Once they do start to work, the results are usually good.

Read more about:

diagnosing acne

treating acne

complications of acne

Why do I have acne?

Acne is most commonly linked to the changes in hormone levels during puberty, but can start at any age.

Certain hormones cause the grease-producing glands next to hair follicles in the skin to produce larger amounts of oil (abnormal sebum).

This abnormal sebum changes the activity of a usually harmless skin bacterium called P. acnes, which becomes more aggressive and causes inflammation and pus.

The hormones also thicken the inner lining of the hair follicle, causing blockage of the pores (opening of the hair follicles). Cleaning the skin doesn't help to remove this blockage.

Other possible causes

Acne is known to run in families. If both your mother and father had acne, it's likely that you'll also have acne.

Hormonal changes, such as those that occur during the menstrual cycle or pregnancy, can also lead to episodes of acne in women.

There's no evidence that diet, poor hygiene or sexual activity play a role in acne.

Read more about the causes of acne, including some common acne myths.

Who's affected?

Acne is very common in teenagers and younger adults. About 80% of people aged 11 to 30 are affected by acne.

Acne is most common in girls from the ages of 14 to 17, and in boys from the ages of 16 to 19.

Most people have acne on and off for several years before their symptoms start to improve as they get older. Acne often disappears when a person is in their mid-twenties.

In some cases, acne can continue into adult life. About 5% of women and 1% of men have acne over the age of 25.

Causes

Treatment for acne depends on how severe it is. It can take several months of treatment before acne symptoms improve.

The various treatments for acne are outlined below. You can also read a summary of the pros and cons of the treatments for acne, allowing you to compare your treatment options.

If you just have a few blackheads, whiteheads and spots, you should be able to treat them successfully with over-the-counter gels or creams (topical treatments) that contain benzoyl peroxide.

Treatments from your GP

See your GP if your acne is more widespread, as you probably need prescription medication. For example, if:

• you have a large number of papules and pustules
• over-the-counter medication hasn't worked

Prescription medications that can be used to treat acne include:

• topical retinoids
• topical antibiotics
• azelaic acid
• antibiotic tablets
• in women, the combined oral contraceptive pill
• isotretinoin tablets

If you have severe acne, your GP can refer you to an expert in treating skin conditions (dermatologist). For example, if you have:

• a large number of papules and pustules on your chest and back, as well as your face
• painful nodules

A combination of antibiotic tablets and topical treatments is usually the first treatment option for severe acne. If this doesn't work, a medication called isotretinoin may be prescribed.

Hormonal therapies or the combined oral contraceptive pill can also be effective in women who have acne. However, the progestogen-only pill or contraceptive implant can sometimes make acne worse.

Many of these treatments can take two to three months before they start to work. It's important to be patient and persist with a recommended treatment, even if there's no immediate effect.

Topical treatments (gels, creams and lotions)

Benzoyl peroxide

Benzoyl peroxide works as an antiseptic to reduce the number of bacteria on the surface of the skin. It also helps to reduce the number of whiteheads and blackheads, and has an anti-inflammatory effect.

Benzoyl peroxide is usually available as a cream or gel. It's used either once or twice a day. It should be applied 20 minutes after washing to all of the parts of your face affected by acne.

It should be used sparingly, as too much can irritate your skin. It also makes your face more sensitive to sunlight, so avoid too much sun and ultraviolet (UV) light, or wear sun cream.

Benzoyl peroxide can have a bleaching effect, so avoid getting it on your hair or clothes.

Common side effects of benzoyl peroxide include:

• dry and tense skin
• a burning, itching or stinging sensation
• some redness and peeling of the skin

Side effects are usually mild and should pass once the treatment has finished.

Most people need a six-week course of treatment to clear most or all of their acne. You may be advised to continue treatment less frequently to prevent acne returning.

Topical retinoids

Topical retinoids work by removing dead skin cells from the surface of the skin (exfoliating) which helps to prevent them building up within hair follicles.

Tretinoin and adapalene are topical retinoids used to treat acne. They're available in a gel or cream and are usually applied once a day before you go to bed.

Apply to all the parts of your face affected by acne 20 minutes after washing your face.

It's important to apply topical retinoids sparingly and avoid excessive exposure to sunlight and UV.

Topical retinoids aren't suitable for use during pregnancy, as there's a risk they might cause birth defects.

The most common side effects of topical retinoids are mild irritation and stinging of the skin.

A six-week course is usually required, but you may be advised to continue using the medication less frequently after this.

Topical antibiotics

Topical antibiotics help kill the bacteria on the skin that can infect plugged hair follicles. They're available as a lotion or gel that is applied once or twice a day.

A six- to eight-week course is usually recommended. After this, treatment is usually stopped, as there's a risk that the bacteria on your face could become resistant to the antibiotics. This could make your acne worse and cause additional infections.

Side effects are uncommon, but can include:

• minor irritation of the skin
• redness and burning of the skin
• peeling of the skin

Azelaic acid

Azelaic acid is often used as an alternative treatment for acne if the side effects of benzoyl peroxide or topical retinoids are particularly irritating or painful.

Azelaic acid works by getting rid of dead skin and killing bacteria. It's available as a cream or gel and is usually applied twice a day (or once a day if your skin is particularly sensitive).

The medication doesn't make your skin sensitive to sunlight, so you don't have to avoid exposure to the sun.

You'll usually need to use azelaic acid for a month before your acne improves.

The side effects of azelaic acid are usually mild and include:

• burning or stinging skin
• itchiness
• dry skin
• redness of the skin

Antibiotic tablets

Antibiotic tablets (oral antibiotics) are usually used in combination with a topical treatment to treat more severe acne.

In most cases, a class of antibiotics called tetracyclines is prescribed, unless you're pregnant or breastfeeding.

Pregnant or breastfeeding women are usually advised to take an antibiotic called erythromycin, which is known to be safer to use.

It usually takes about six weeks before you notice an improvement in your acne.

Depending on how well you react to the treatment, a course of oral antibiotics can last four to six months.

Tetracyclines can make your skin sensitive to sunlight and UV light, and can also make the oral contraceptive pill less effective during the first few weeks of treatment.

You'll need to use an alternative method of contraception, such as condoms, during this time.

Hormonal therapies

Hormonal therapies can often benefit women with acne, especially if the acne flares up around periods or is associated with hormonal conditions such as polycystic ovary syndrome.

If you don't already use it, your GP may recommend the combined oral contraceptive pill, even if you're not sexually active. This combined pill can often help improve acne in women, but may take up to a year before the full benefits are seen.

Co-cyprindiol

Co-cyprindiol is a hormonal treatment that can be used for more severe acne that doesn't respond to antibiotics. It helps to reduce the production of sebum.

You'll probably have to use co-cyprindiol for two to six months before you notice a significant improvement in your acne.

There's a small risk that women taking co-cyprindiol may develop breast cancer in later life.

For example, out of a group of 10,000 women who haven't taken co-cyprindiol, you would expect 16 of them to develop breast cancer by the time they were 35. This figure rises to 17 or 18 for women who were treated with co-cyprindiol for at least five years in their early twenties.

There's also a very small chance of co-cyprindiol causing a blood clot. The risk is estimated to be around 1 in 2,500 in any given year.

It's not thought to be safe to take co-cyprindiol if you're pregnant or breastfeeding. Women may need to have a pregnancy test before treatment can begin.

Other side effects of co-cyprindiol include:

• bleeding and spotting between your periods, which can sometimes occur for the first few months
• headaches
• sore breasts
• mood changes
• loss of interest in sex
• weight gain or weight loss

Isotretinoin

Isotretinoin has a number of beneficial effects:

• it helps to normalise sebum and reduce how much is produced
• it helps to prevent follicles becoming clogged
• it decreases the amount of bacteria on the skin
• it reduces redness and swelling in and around spots

However, the drug can also cause a wide range of side effects. It's only recommended for severe cases of acne that haven't responded to other treatments.

Because of the risk of side effects, isotretinoin can only be prescribed by a specially trained GP or a dermatologist.

Isotretinoin is taken as a tablet. Most people take a four- to six-month course. Your acne may get worse during the first 7 to 10 days of treatment. However, this is normal and soon settles.

Common side effects of isotretinoin include:

• inflammation, dryness and cracking of the skin, lips and nostrils
• changes in your blood sugar levels
• inflammation of your eyelids (blepharitis)
• inflammation and irritation of your eyes (conjunctivitis)
• blood in your urine

Rarer side effects of isotretinoin include:

• inflammation of the liver (hepatitis)
• inflammation of the pancreas (pancreatitis)
• kidney disease

Because of the risk of these rarer side effects, you'll need a blood test before and during treatment.

Isotretinoin and birth defects

Isotretinoin will damage an unborn baby. If you're a woman of childbearing age:

• don't use isotretinoin if you're pregnant or you think you're pregnant
• use one, or ideally two, methods of contraception for one month before treatment begins, during treatment and for one month after treatment has finished
• have a pregnancy test before, during and after treatment

You'll be asked to sign a form confirming that you understand the risk of birth defects and are willing to use contraceptives to prevent this risk, even if you're not currently sexually active.

If you think you may have become pregnant when taking isotretinoin, contact your dermatologist immediately.

Isotretinoin is also not suitable if you're breastfeeding.

Isotretinoin and mood changes

There have been reports of people experiencing mood changes while taking isotretinoin. There's no evidence that these mood changes were the result of the medication.

However, as a precaution, contact your doctor immediately if you feel depressed or anxious, have feelings of aggression or suicidal thoughts.

Non-pharmaceutical treatments

Several treatments for acne don't involve medication.

These include:

• comedone extractor – a small pen-shaped instrument that can be used to clean out blackheads and whiteheads
• chemical peels – where a chemical solution is applied to the face, causing the skin to peel off and new skin to replace it
• photodynamic therapy – where light is applied to the skin in an attempt to improve symptoms of acne

However, these treatments may not work and can't be routinely recommended.