There are 6 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 colour
• Whiteheads – have a similar appearance to blackheads, but may be firmer and will not 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.

Things patients can try if they have acne

• 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.
• Do not try to "clean out" blackheads or squeeze spots. This can make them worse and cause permanent scarring.
• Avoid make-up, skincare and suncare products that are oil-based (sometimes labelled “comedogenic”). Use water-based non-comedogenic products, as they’re less likely to block the pores in their skin.
• Completely remove make-up before going to bed.
• If dry skin is a problem, use a fragrance-free water-based emolient.
• Regular exercise cannot improve acne, but it can boost mood and improve self-esteem.
• Shower as soon as possible once finishing exercising as sweat can irritate acne.
• Wash hair regularly and try to avoid letting hair fall across the face.