Introduction

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 Carbuncles and carry the greatest risk of causing permanent scarring

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 controlyour spotswith 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.

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.

About 80% of people aged 11to 30are affected by acne.

Acne is most common in girls from the ages of 14to 17, and in boys from the ages of 16to 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. About5% ofwomen and 1% of men have acne over the age of 25.