Acne is a condition which occurs mainly in the teen and young adult age groups. The pilosebaceous units (each containing a hair follicle and oil gland) on the face and trunk are over-stimulated by androgen, which causes over-production of sebum and keratin. Associated with this, there is generally inflammation and infection which worsen and complicate the acne.
Classification of Acne
There are several classifications of acne:
Non-Inflammatory Acne
As a result of the over-production of sebum and keratin, the pores get "plugged," causing whiteheads and blackheads. These are open and closed comedones. This can be treated effectively with topical agents.
Inflammatory Acne
Inflammation may set in to a greater or lesser degree, at which stage the lesions become papules or pustules less than one centimetre (larger pimples). Topical agents can still be used here, but they may not be sufficient, and may require oral agents to be used in addition.
Nodulocystic Acne
If the lesions form nodules and cysts larger than one centimetre, this is then called nodulocystic acne. This has a greater risk of scarring, and needs oral agents for treatment.
Modes of Acne Treatment
There are several types of acne treatments, including the following:
Topical Acne Treatment
- Topical retinoids are effective against both the inflammatory and non-inflammatory types of acne. As a result they may be useful alone, or they may be used in combination with other agents like antibiotics. Their side effects include drying and sensitivity of the skin. Moisturizing and sun protection are essential. The retinoids are best applied at night rather than in the morning because of the sun
- Benzoyl peroxide is a bactericidal (bacteria-killing) agent that is frequently used in combination with antibiotics to help prevent the resistance which the bacteria quickly develop to the antibiotics.
- Topical antibiotics can be most effective, unless resistance develops. If resistance occurs after a period of a few months of the acne having improved, acne will get worse while still on the treatment. Most frequently used are erythromycin or clindamycin. The antibiotics may cause a contact dermatitis if there is an allergy.
Systemic Acne Treatment
- Oral antibiotics. The most frequently found amongst the bacteria which cause problems in acne is the Propionibacterium acnes. Using antibiotics has long been one of the main ways of effectively treating acne. However, with the increasing problem of resistance, their efficacy is considerably reduced. Most frequently used are doxycycline and minocycline (generally the most effective of the group), erythromycin (for those who can’t use the previous two, such as pregnant women. There is a bit more resistance in this group), and trimethoprim-sulfamethoxazole (for those who can’t use the previous ones). Treating in combination with topical benzoyl peroxide possibly helps to reduce the amount of resistance.
- Hormonal agents such as oral contraceptives containing oestrogen can be effective. Cyproterone acetate is an anti-androgen, and seeing as the acne process has been induced by the production of androgen, the use of cyproterone can be most effective in controlling acne in women. The oral contraceptive containing oestrogen and cyproterone is not approved in the US, although it is available in many other countries. The hormonal option can be useful in a young woman who needs help with her menstrual cycle, or happens to also want contraception. Spironolactone is also an anti-androgen, but it has a number of side effects, including on blood pressure and potassium levels. Its main use generally would be as a diuretic, in the treatment of hypertension.
- Isotretinoin (e.g. Accutane) is a systemic form of a retinoid – a vitamin A derivative. It is extremely effective and is used in severe nodular acne that doesn't respond to other forms of treatment, or where scarring is occurring. It is kept for the more severe cases because of the serious nature of the side effects that it has. It is potently teratogenic (i.e. it may cause congenital malformations if taken in pregnancy). Female patients are required to have two negative pregnancy tests before starting the therapy, as well as a test monthly while she is on the drug. She needs to be using two forms of contraception starting a month before beginning the isotretinoin, and continue them until at least a full month after stopping.
The dosage and length of time on the isotretinoin will differ between patients, according to body weight, and severity of the acne. Generally the course may last two months. Initially, the acne may worsen, before it starts to improve. The patient is given a rest at the end of the two months during which time the skin may continue to improve. If necessary the doctor may prescribe a further course.
Common side effects include drying of the skin, mucous membranes, eyes and hair. There may be effects on the liver, with the result that liver functions and a full blood count get checked regularly while the patient is on the drug. An upset bowel and mood changes may be amongst the various other side effects which can occur.
Looking at the medications available for acne treatment, the vast majority of patients can be treated with topical medications, generally available over-the-counter. It is the minority that require going on to the oral drugs.
Contrary to popular belief, diet has not been demonstrated to alter the course of acne at all. Herbal and alternative therapies have also not been scientifically demonstrated to be of definite benefit.
References:
Kircik L, 2006 “Topical Acne Treatment” 14Juy 2010
Fulton James, June 21 2010 “Acne Vulgaris: Treatment & Medication” 14 July 2010
Strauss John S., et al Feb 2007 “Guidelines of Care for Acne Vulgaris Management” 14 July 2010
Sally Powrie - I am a wife, mother of 5, mother-in-law of 2, grandmother of 2, general practitioner of more than 20 years standing, and for the last 4 ...
