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 are 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:
- Do not 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 cannot 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 cannot 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 is 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, you must see your doctor/ 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.
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 is likely that you will 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 is no evidence that diet, poor hygiene or sexual activity play a role in acne.
Table showing the main causes of Acne.
Who is 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
Acne is caused when tiny holes in the skin, known as hair follicles, become blocked. Sebaceous glands are tiny glands found near the surface of your skin. The glands are attached to hair follicles, which are small holes in your skin that an individual hair grows out of.
Sebaceous glands lubricate the hair and the skin to stop it drying out. They do this by producing an oily substance called sebum. In acne, the glands begin to produce too much sebum. The excess sebum mixes with dead skin cells and both substances form a plug in the follicle.
If the plugged follicle is close to the surface of the skin, it bulges outwards, creating a whitehead. Alternatively, the plugged follicle can be open to the skin, creating a blackhead. Normally harmless bacteria that live on the skin can then contaminate and infect the plugged follicles, causing papules, pustules, nodules or cysts.
Testosterone
Teenage acne is thought to be triggered by increased levels of a hormone called testosterone, which occurs during puberty. The hormone plays an important role in stimulating the growth and development of the penis and testicles in boys, and maintaining muscle and bone strength in girls.
The sebaceous glands are particularly sensitive to hormones. It's thought that increased levels of testosterone cause the glands to produce much more sebum than the skin needs.
Acne in families
Acne can run in families. If your parents had acne, it's likely that you'll also develop it. One study has found that if both your parents had acne, you are more likely to get more severe acne at an early age. It also found that if one or both of your parents had adult acne, you're more likely to get adult acne too.
Acne in women
More than 80% of cases of adult acne occur in women. It's thought that many cases of adult acne are caused by the changes in hormone levels that many women have at certain times. These times include:
- periods – some women have a flare-up of acne just before their period
- pregnancy – many women have symptoms of acne at this time, usually during the first three months of their pregnancy
- polycystic ovary syndrome – a common condition that can cause acne, weight gain and the formation of small cysts inside the ovary.
Other triggers
Other possible triggers of an acne flare-up include:
- some cosmetic products – however, this is less common as most products are now tested, so they don't cause spots (non-comedogenic)
- certain medications – such as steroid medications, lithium (used to treat depression and bipolar disorder) and some anti-epileptic drugs (used to treat epilepsy)
- regularly wearing items that place pressure on an affected area of skin, such as a headband or backpack
- smoking – which can contribute to acne in older people.
Schematic diagram showing the different reasons that cause acne, depending on the body zone that acne is seen.
Acne myths
Despite being one of the most widespread skin conditions, acne is also one of the most poorly understood. There are many myths and misconceptions about it:
"Acne is caused by a poor diet" - So far, research hasn't found any foods that cause acne. Eating a healthy, balanced diet is recommended because it's good for your heart and your health in general.
"Acne is caused by having dirty skin and poor hygiene" - Most of the biological reactions that trigger acne occur beneath the skin, not on the surface, so the cleanliness of your skin has no effect on your acne. Washing your face more than twice a day could just aggravate your skin.
"Squeezing blackheads, whiteheads and spots is the best way to get rid of acne" - This could actually make symptoms worse and may leave you with scarring.
"Sexual activity can influence acne" - Having sex or masturbating will not make acne any better or worse.
"Sunbathing, sunbeds and sunlamps help improve the symptoms of acne" - There is no conclusive evidence that prolonged exposure to sunlight or using sunbeds or sunlamps can improve acne. Many medications used to treat acne can make your skin more sensitive to light, so exposure could cause painful damage to your skin, and also increase your risk of skin cancer.
"Acne is infectious" - You cannot pass acne on to other people.
Diagnosis
Your doctor/ GP can diagnose acne by looking at your skin. This involves examining your face, chest and back for the different types of spot, such as blackheads or sore, red nodules.
How many spots you have and how painful and inflamed they are will help determine how severe your acne is. This is important in planning your treatment. Four grades can be used to measure the severity of acne:
- grade 1 (mild) – acne is mostly confined to whiteheads and blackheads, with just a few papules and pustules
- grade 2 (moderate) – there are multiple papules and pustules, which are mostly confined to the face
- grade 3 (moderately severe) – there's a large number of papules and pustules, as well as the occasional inflamed nodule, and the back and chest are also affected by acne
- grade 4 (severe) – there's a large number of large, painful pustules and nodules.
Acne in women
If acne suddenly starts in adult women, it can be a sign of a hormonal imbalance, especially if it's accompanied by other symptoms such as:
- excessive body hair (hirsutism)
- irregular or light periods.
The most common cause of hormonal imbalances in women is polycystic ovary syndrome (PCOS). PCOS can be diagnosed using a combination of ultrasound scans and blood tests.
Treatment
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.
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 doctor/ GP
You should 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 has not 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.
