Acne is a general term used to describe inflammation of the oil-producing glands that surround hair roots.  These glands – sebaceous glands – produce the skin’s natural oil (or sebum) which acts as a water repellent.

Acne vulgaris (usually referred to just as acne) is the common form of acne, which usually starts at puberty.  At this age, the sebaceous glands become active under the influence of male sex hormones (androgens), which are produced by the testes in males and by the adrenal glands in both males and females.  The level of production of these hormones increases up to about the age of 25 years, after which it levels out.  People who get acne do not have higher levels of male sex hormones than people who do not develop acne and it may be that their sebaceous glands are more sensitive to stimulation by male sex hormones.

Acne (vulgaris) affects the sebaceous glands in the skin of the face, neck, middle of the chest and back.  These are areas where the glands are most active.  Although acne is related to the production of male hormones, it occurs only slightly more commonly in males than females.  We do not know why some people get acne and others do not nor why some just get mild acne and others get severe acne.

In acne, the outlets from sebaceous glands get blocked by skin cells and debris, and this forms what are called blackheads (or comedones).  The glands then swell up and become infected and inflamed, to produce the red pimples (papules) and yellow pimples (pustules) of acne (zits).  If the outlet is blocked completely the glands may swell right up to form a cyst; some individuals may get an overgrowth of scar tissue (called keloid) which produces irregular lumps and bumps in the affected area.

Some drugs may cause acne

Corticosteroid drugs may make the grease glands more sensitive and trigger acne in some people.  Acne may also be caused by bromides, ethionamide, haloperidol, halothane, iodides, isoniazid, lithium, phenytoin, trimethadione and male sex hormones.

Because we do not know why some individuals get acne and others do not, there are all kinds of ideas about what causes it.  There is no convincing evidence that factors in the diet – for example, chocolates, fats or sugars – aggravate acne.

Acne may get worse if you are tense and anxious, and of course it may get better if you are less tense about your condition because you think or hope that the treatment you are using will help to improve it.  Acne may get worse just before a period and this may be due to fluid retention caused by female sex hormones.  The fluid retention may cause swelling of the outlets from the glands, causing them to become blocked.  Sweating may produce similar effects.

Oral contraceptive preparations that contain a high concentration of oestrogen may make acne worse.

Contact of the skin with oil may cause acne to develop; for example, working with engineering oils or the regular application to the face of cosmetics that contain oils.  People who live in sunny climates suffer less from acne than people who live in cloudy climates.  This is why sun-ray treatment has been used, but its beneficial effects are unpredictable.

Treatment of acne

There is no specific treatment for acne and it is often best to use what suits you or try different treatments, but do not be persuaded to use expensive preparations when the simplest and cheapest may be the best.

When deciding on the treatment of acne it helps to divide it into superficial acne and deep acne, according to its severity.

Superficial acne is characterised by comedones – which may be open (blackheads) or closed (whiteheads) – inflamed pimples (papules) and small superficial cysts and swellings containing pus (pustules).  In deep acne papules and pus-filled cysts also develop deep in the skin.

Healing without scars is common in superficial acne but scarring often occurs in deep acne.

Superficial acne usually responds to topical application whereas deep acne usually requires drugs by mouth in addition to topical applications.

Skin applications

Cleansing preparations; The important part of treatment of acne is to keep the skin free from grease by cleaning the skin regularly.  The application of a hot, wet face cloth to the face followed by washing with ordinary soap and water may be all that is needed.  If this does not work, a detergent solution such as cetrimide should be used.  The affected area should be washed with the solution twice daily, avoiding too much rubbing.  Cosmetics and other applications that contain fats or oils should not be used.  Also oily hair dressings should be avoided and the hair should be shampooed regularly.

Drying and peeling preparations; In addition to keeping the skin clean and free from excess grease, it may be necessary to apply preparations that dry and peel the skin and stop blackheads from forming.  Products that contain sulphur or salicylic acid are used for this purpose.  Preparations containing resorcinol should not be used because of the risk of absorption into the blood stream and its effects in knocking out the production of thyroid hormones by the thyroid gland.

The most frequently used chemical is benzoyl peroxide, which is present in many preparations.  It not only dries and peels the skin, it also has antiseptic properties.

Vitamin A derivatives; A vitamin A derivative called tretinoin (Retin-A), which is available only on prescription, applied as a cream, gel or lotion, may be useful in some individuals with moderately severe acne but it may produce redness and peeling for several days.  Too frequent use may cause dermatitis, so it may help to use the application in the mornings.  Tretinoin should not be applied to the eyes, up the nose or on the creases of the mouth.  The acne may appear to be worse at first, and it may take up to 4 weeks before any improvement occurs.

Abrasive preparations: Abrasives may be used to help peeling and cleansing of the skin and some individuals may occasionally find these of benefit.  They include Brasivol and Ionax.

Anti-bacterial preparations: A tetracycline antibiotic (e.g. Topicycline) applied to the skin may help to reduce bacterial infection in the sebaceous glands and may possibly produce some anti-inflammatory effects.  A tetracycline antibiotic application may be worth trying in mild acne, but it may cause an allergic rash in susceptible individuals and it may cause bacteria on the skin to become resistant to tetracyclines.  Other antibiotics included in acne applications include clindamycin (Dalacin T solution) and erythromycin (Stiemycin solution; in Zineryt with zinc acetate). These antibiotics are only available with a doctor’s prescription. For the use of anti-bacterial drugs by mouth, see later.

Antiseptic preparations: Hydroxyquinoline kills bacteria and fungi, and is included in some acne preparations.  It may produce irritation and redness. 

Benzoyl peroxide, which is used as a peeling agent (see earlier), also has antiseptic properties.  It is a popular constituent of acne applications.  It may cause an initial stinging effect and, rarely, an allergic reaction.  It may bleach hair and clothes.

Sulphur, which is used to produce peeling, also possesses some antiseptic effects.

Warning: Greasy creams or ointments and corticosteroid applications may make acne worse.

Drugs taken by mouth to treat acne

Antibiotics: Bacteria that normally live in the oil-producing (sebaceous) glands may produce irritant substances from the oil which cause inflammation.  Antibiotics (e.g. tetracyclines) that dissolve in fat can kill these bacteria and help to reduce the inflammation.  Therefore, if the acne is moderate or severe or does not respond to local applications, it is worth adding an anti-bacterial drug by mouth such as a tetracycline (e.g.doxycycline, minocycline or oxytetracycline) or co-trimoxazole or erythromycin.  The anti-bacterial drug must be taken daily: maximum improvement usually occurs within 3-4 months but sometimes treatment has to be continued for a longer period.  This is powerful treatment and any benefit must be balanced against the risks of taking an anti-bacterial drug daily for such a long period of time. It is important to discuss this with your doctor to ensure you derive most benefit from the treatment.

Warnings: Tetracycline antibiotics should not be used in pregnancy, so women taking a tetracycline daily by mouth for the treatment of their acne should not be pregnant and should avoid getting pregnant while on treatment.

Long-term use of antibiotics applied to the skin and/or taken by mouth may cause a super infection of the skin around the nose and central part of the face, causing redness and pustules.  Treatment of this super infection is often difficult, and should be based on trying to identify the infecting micro-organism, testing its sensitivity to antibiotics and using the appropriate antibiotic.

Hormones: Male sex hormones are associated with the development of acne, and female sex hormones (oestrogens) may therefore reduce some of their effects.  Obviously oestrogens cannot be used in males, and because of the risks of oestrogens, they should not be used alone in females.  A combination of an oestrogen with a progestogen reduces the risks, so a combined oral contraceptive may help acne in some women, but contraceptive pills with a high proportion of oestrogen may make acne worse.

Cyproterone is an anti-male sex hormone and combined with an oestrogen (ethinyloestradiol), it may be beneficial in women who suffer from severe acne that has not responded to other treatments.  The combination product is marketed under the name of Dianette.  It also helps to reduce male-type hair growth (e.g. on the face) in women and can act as an oral contraceptive.

Isotretinoin; This a vitamin A derivative that is effective in some people with severe and nodular acne, and may prevent scarring.  It reduces oil production and helps to unblock hair follicles, alters bacterial growth in the sebaceous glands and produces peeling of the superficial layer of the skin.  It is best used in individuals who have failed to respond to antibiotics by mouth and/or who have severe deep acne.

It may produce serious harmful effects so any possible benefits need to be weighed against the risks.  It should be used only when other treatments have failed and only under specialist medical supervision.

Zinc: There is no convincing evidence from adequate and well controlled studies that zinc sulphate by mouth has any beneficial effect.

Acne Rosacea

Acne rosacea is a chronic flushing of the forehead, nose, cheeks and chin, with red pimples (acne papules) and yellow pimples (acne pustules).  It is more common in people with fair complexions and it usually comes on in middle age.  More women than men suffer from acne rosacea, and it is usually made worse by sunlight.  The nose may be affected and become enlarged (rhinophyma).

No cause is known, and treatment consists of trying to avoid those things that make the face flush – hot drinks (particularly tea), sitting in front of a hot fire, hot spicy food and alcohol.  Regular daily use for a month or two of an antibiotic by mouth such as oxytetracycline may control the acne pimples in some people, particularly if it is combined with local treatments discussed earlier under the treatment of acne vulgaris.

Corticosteroid applications should not be used to treat acne rosacea because they make it worse and may cause a severe flare-up if treatment is stopped.