Acne

• Acne is the result of a change in the activities of the sebaceous (oil producing) glands in the skin.
• Human skin is divided into two layers; a thin, outer layer called the epidermis, and a deeper layer called the dermis. The dermis is much thicker than the outer epidermis and contains all of the nerves and blood vessels that the skin requires.
• The dermis also contains the hair roots (‘follicles’). Associated with each hair root is a sebaceous gland. The oily liquid that the sebaceous glands produce is called sebum, which passes out of the follicle to the outer surface of the skin. Here it functions to lubricate the skin and keep it flexible.
• The classic symptoms of acne are the result of an overproduction of sebum by the sebaceous glands, which often starts around the time of puberty. As the body starts the transition from child to adult, the levels of certain hormones in the blood rises. Whilst there are many hormones in the body, the hormones that are thought to be involved in the development of acne are androgens – masculinising hormones which are present both in men and women.
• Sebaceous glands are very sensitive to androgens, and respond by producing more sebum; the glands also increase in size. When the sebum reaches the surface of the skin, it reacts with the atmosphere and becomes thicker. With the exit from the follicle now partly obstructed by the thickened sebum, the flow from the gland slows down; bacteria from the skin can then infect the stagnating sebum left in the gland. As the sebaceous glands are often enlarged, sebum can escape from the gland into the surrounding dermis where it causes localised irritation and inflammation.
• Whiteheads or blackheads (‘comedones’) are seen when the opening from the hair follicle finally becomes blocked by the thickened sebum, skin bacteria and cellular debris from inside the follicle. Red, inflamed spots may be seen and are probably the result of the leaking sebum irritating the dermis. Sometimes small pus-filled blisters develop in the inflamed spot. These usually settle down in a few days. The dark tip of a blackhead is caused by an accumulation of melanin, a natural skin pigment.
• While these symptoms are mostly seen in teenagers, they can occasionally be seen in mature adults as well. Women make up the majority of these mature cases; here the acne may be due to an increased sensitivity to androgens.

• “Spots are caused by a lack of cleanliness” – Having spots does not mean you’re dirty. (The dark tips of blackheads are not dirt – they’re an accumulation of melanin, a normal skin pigment)
• “Acne is contagious” – You can’t catch acne by touching or even kissing someone who has the symptoms.
• “Acne only occurs on the face” – Spots are most common on the face, but in severe cases they may also spread down the shoulders, upper back and chest.

• “Acne gets worse just before a period” – Most women find their spots are worse in the week before their period, because of the hormone changes which occur at that time.
• “Taking the Pill can make acne worse” – The contraceptive pill does not actually cause acne, but it can influence the severity of your spots. If you have spots, ask your doctor to prescribe a contraceptive pill which will not make your acne worse.
• “Acne can be affected by pregnancy” – Pregnancy can have an effect, but it is unpredictable. In some women, spots virtually disappear during pregnancy, though they may recur afterwards; if you are less lucky, you may find pregnancy causes acne to flare up.
• “Acne can be aggravated by cosmetics” – Make-up can conceal spots very effectively, but you need to choose good quality, non-greasy products, or you may block the skin pores and make your spots worse. Products described as “non-comedogenic” are specially designed not to block skin pores.
• “My job aggravates my acne” – Certain jobs which involve working in hot, humid environments, such as kitchens or laundries, can make the spots worse, as excessive sweating can block the skin pores.

1. Do I have acne?

What are the signs of acne?