- Acne is a common skin disorder.
- Acne is not limited to teenagers.
- Acne and its severity often run in families.
- People with acne often have an oily (greasy) skin.
- There is no cure for acne, but effective treatment is available.
Acne is a skin condition that occurs when the sebaceous (oil-secreting) glands in the skin and along hair shafts become clogged and inflamed, and infected by bacteria.
Blackheads and whiteheads form in the clogged pores. Blackheads are small, usually flat spots with black centres. Whiteheads are similar, but because they are closed, they don't have dark centres. Both blackheads and whiteheads may develop into swollen, tender papules (pimples) and pustules.
If acne is severe, large pimples – called cysts, nodules or cystic lesions – form firm swellings deep under the skin. They become inflamed and may develop into painful lumps, leading to scarring.
Acne is not limited to teenagers. Rarely, babies are born with acne and some people get acne for the first time after they’ve reached adulthood. Most people outgrow acne, but in women it may last until the menopause. 5% of women of 40 years of age have acne, but only 1% of men in that age group.
Acne can develop on your face, neck, chest, shoulders or back. The severity may differ from person to person and may fluctuate over time. Acne often has an adverse emotional effect on sufferers.
There is no cure for acne, but effective treatment is available. Severe acne requires medical treatment.
Let's start by explaining the anatomy of the skin. The hair consists of three components:
- The hair follicle itself with an emerging hair shaft
- The sebaceous (oil) gland which opens into the hair follicle
- The sweat (apocrine) gland which opens into the hair follicle
Four factors are involved in the development of acne:
- Increased production of oil stimulated by androgenic (male sex) hormones. During the teens, hormones stimulate hair growth, as well as oil secretion by the sebaceous glands. Hormonal changes can stimulate sebaceous glands to produce more sebum. Therefore, anything that raises hormone levels (for example pregnancy, stress, menstrual periods and certain medicines, such as corticosteroids) could aggravate acne. The male sex hormone testosterone, which is present in both men and women, is mainly responsible, but the female sex hormone progesterone also contributes to acne in women.
(Some babies are born with acne because their mothers pass certain hormones on to them just before birth. This is rare and usually self-limiting.)
- Obstruction of the opening of the follicle caused by increased production of scales (keratin)
- Infection by a bacterium, namely Propionibacterium acnes. The bacteria Propionibacterium acnes and Staphylococcus epidermis occur naturally in hair follicles. If there are too many bacteria, they may secrete enzymes that break down sebum, promoting inflammation in the follicle. Some people may be more sensitive to this reaction than others, making their acne more severe.
- Rupture (breakage of the follicle leading to inflammation
Genes and skin type may predispose a person to acne. Genetic factors may play a role.
Stress may aggravate acne, but cannot cause it. Acne may cause stress.
The earliest lesions of acne are whiteheads and blackheads.
The stages or severity of acne are:
- Whiteheads (clogged pores not open to the surface and medically known as closed comedones)
- Blackheads (clogged pores open to the surface and medically known as open comedones)
- Breakage of these structures leads to the development of all other lesions – the real pimple. When whiteheads rupture the hair follicle wall, pimples are formed. Solidified sebum, dead cells from the pore and bacteria are released into the skin, creating a pimple (pustule). This stage is called inflammatory acne.
- If pustules become infected, the infection may penetrate deep into the skin and form cysts (cystic acne).
- The cysts may rupture and leave temporary or permanent scars.
Skin lesions most commonly involve the face, neck, shoulders and back.
When you look at a patient with acne you may see:
- Blackheads – dark spots with open pores at the centre
- Increased greasiness of the skin
When these lesions are present, the condition is termed non-inflammatory acne:
- Small red bumps
- Red swellings or bumps that are visibly filled with pus (zits/pimples/pustules) – on the face, chest, shoulders, neck and/or upper back
- Large, inflamed, red, firm fluid-filled lumps (nodules) under the skin
- Large, inflamed, red, soft bumps (cysts) under the skin that may become as large as 2,5 cm across
Healing of inflammatory lesions may lead to scarring and post-inflammatory pigmentation (dark spots).
A patient with acne may show only non-inflammatory lesions or a combination of non-inflammatory and inflammatory lesions with or without scars and brown spots.
Acne may cause embarrassment, frustration and anger, and sufferers tend to withdraw from school and social activities. Acne certainly impairs quality of life.
Prevalence and course
About 90% of all teenagers get acne, while 20% of all cases are in adults.
Acne in babies is uncommon and results from the effect of maternal hormones.
Acne usually resolves in early adulthood. Some people develop acne for the first time after they have reached adulthood. Five percent of women older than 40 may still be troubled by acne. Only one percent of men in a similar group have acne.
The severity may differ from person to person and may fluctuate over time.
Teenage boys tend to have more severe acne than teenage girls.
Acne is most prevalent in the teens and early adulthood, mainly because of hormone production. However, many people have acne throughout their lives. In most people who develop acne, it will last 6-10 years. Blackheads and whiteheads (non-inflammatory acne) may develop into pimples or pustules (inflammatory acne), and pimples may develop into cysts.
- Acne and its severity often run in families.
- People with oily skin are more prone to develop acne.
- Teenage boys tend to have more severe acne than teenage girls.
When to see a doctor
- In all cases of inflammatory acne
- If non-inflammatory acne gets worse or does not respond to home treatment within two to three months
- If you develop emotional problems as a result of your acne
- If you develop scars or marks on your skin after a pimple has healed
- If your pimples become large and hard or filled with fluid
- If you notice other symptoms, such as hair growth on the chin (if you’re a woman) or bone and muscle pain (both sexes) or any other sign of overproduction of androgens
- If you suspect new prescription medication is causing your acne
- If you suspect that greasy cosmetics or other topical preparations are aggravating your acne
Acne is easily diagnosed by physical examination and medical history.
When signs of of androgen excess are present such as menstrual irregularity, hair loss on the scalp and hair growth on the body, specialist referral is essential to exclude overproduction of androgenic hormones by the ovaries or adrenal glands.
The diagnosis of acne is usually straightforward, but acne-like lesions may be caused by systemic medication (eg. cortisone), cortisone applied to the face, and, greasy cosmetics.
Rosacea is characterised by redness, red bumps and pimples. Comedones are absent. Patients are usually middle aged.
No treatment is needed for the occasional pimple or two, but if acne causes you distress, something should be done about it. Many different treatments are available, but not each is appropriate for everyone. It is therefore important to keep appointments with your health care provider so that, together, you can determine the right treatment for you. Treatment usually shows an effect only after six to eight weeks.
To prevent acne from getting worse:
- Wash your face twice a day with a gentle soap. Washing your face more often than that may irritate and dry your skin. Avoid hot water. Using hot water can make your acne worse.
- Do not use facial scrubs, astringents and masks unless your doctor has recommended them, because these generally irritate the skin and aggravate acne.
- Do not squeeze, pick, scratch or rub your skin. Squeezing pimples aggravates acne.
- Avoid extreme stress – if necessary, seek counselling and follow a stress management programme. Stress cannot cause acne, but may aggravate it.
There are many over-the-counter medications (creams, lotions, and gels) available. Many of them contain benzoyl peroxide, alpha-hydroxy acids or salicylic acid. These medications should be water-based and hypoallergenic.
Use Cetaphil lotion as a cleanser.
For non-inflammatory acne the treatment of choice is tretinoin (Retin A, retinoic acid), a vitamin A derivative, or adapalene (Differin) or benzoyl peroxide 5% (Panoxyl) in the evening. Both Retin A and Panoxyl may cause redness, burning and scaling (= irritation effect), and sensitivity to sunlight. When this occurs, apply the medication every second evening until the skin settles.
Other drugs that can be used include salicylic acid, tazarotene, and topical antibiotics.
For mild inflammatory acne a topical antibiotic (such as Eryderm) may be added for application in the morning.
For moderate inflammatory acne a systemic (oral) antibiotic, such as tetracycline, is the treatment of choice. Minocycline is preferred by most dermatologists (dosage 50 mg to 100 mg per day). Alternative systemic antibiotics include erythromycin, clindamycin and sulphonamides. Topical treatment (tretinoin included) should be continued to combat inflammation.
Be aware, though, that antibiotics may make women susceptible to yeast infections.
The tetracycline group of drugs causes yellowing of the teeth if taken after the third month of pregnancy.
These drugs should be stopped if you become pregnant and only started again following the completion of breast-feeding.
Tetracyclines must not be given to children before the permanent teeth have erupted because these drugs can cause yellow discolouring of permanent teeth.
For marked inflammatory acne (deep, chronically inflamed cysts), the drug isotretinoin (Roaccutane) may be prescribed. This drug has potentially severe side-effects during pregnancy and the treatment must be monitored.
The rate of cure is between 70 and 80% after five months of treatment. All forms of treatment should be continued for a minimum of three months.
If the condition shows improvement the current therapy regimen may be continued. If not, modification of treatment should be considered.
An anti-androgenic contraceptive pill (Diane-35) may be useful in some women with inflammatory acne.
Triamcinolone, a type of corticosteroid, may be injected directly into cysts. This drug may darken the skin around the lesion.
Dermatologists can surgically remove scars associated with acne. Three techniques are available: dermabrasion, chemical peeling, and laser resurfacing. These treatments are used to remove scarred skin, exposing the underlying, unblemished skin layers.
Controlled exposure to ultraviolet light, as prescribed by a dermatologist, may control outbreaks of acne in some cases.
All of the following may aggravate acne:
- Greasy or oily cosmetics, namely preparations that leave your face shiny following application
- Antiseptic soaps
- Antiseptic scrubs
- Granular scrubs such as Brasivol
- Exfoliating implements such as Buff-Puff
- Topical cortisone-containing preparations such as Neo-Medrol lotion
- Squeezing of skin lesions
- Scratching of skin lesions
- Picking of skin lesion
There is no scientific proof that dietary supplementation or avoidance of certain foodstuffs in the diet improves acne. An exception to the rule is iodised table salt, which may aggravate acne.
The benefit of sunlight exposure is limited.
Reviewed by Prof H.F. Jordaan, MBChB, MMed (Derm), September 2004