Acne (The Long Story)
If you are old enough to read this article you have had first-hand experience with acne. What follows is a rational approach to the treatment of acne. Defined terms are italicized and can be found in Table I. Acne is an all-encompassing term for skin blemishes, on the face, chest, and back. The location of acne directly corresponds to areas where sebaceous follicles are found in high density. The battleground of acne is within the sebaceous follicle, which is basically a hair follicle with attached oil glands. However, the hair is often absent or underdeveloped. The gland produces oil which is called sebum. Androgens (masculinizing hormones produced by both men and women) increase sebum production markedly. It is no coincidence that
acne begins at puberty when sebum production accelerates in response to hormonal changes.
Sebaceous oil would not be a problem if it flowed freely onto the surface as it does on the scalp. However, a second key event in the formation of acne occurs; this event is the formation of an oil-duct plug, known as a microcomedone. Cells lining the duct of the sebaceous follicle peel off the side and combine with the oil to form a tight little plug. Behind this plug acne bacteria proliferate, metabolize the sebum, and create an inflammatory reaction. Rupture of the plugged gland causes the classic pustule (known as a "zit"), and occasionally, if the reaction is more vigorous, larger papules and nodules. So it takes three elements--sebum, a plug, and the ensuing proliferation of acne bacteria--to create acne lesions. Treatment of acne is predicated
on the elimination of one or more of these pathogenic elements.
THE "DIRT" MYTH
Since acne is not due to dirt, excess washing will not be beneficial. You cannot scrub away what is under the skin, and scouring your face usually makes acne worse rather than better. Washing once or twice a day with a mild soap is okay--just do not overdo it.
THE "DIET' MYTH
Although sebum is an oil, it is not produced in excess by dietary intake of various fats such as chocolate or French fries. Dietary restrictions, while good for your arteries, will not alter acne problems. The oil that causes a problem with acne is not on the face. Drying the oil off your face using astringents (drying agents) will not eliminate acne, although you might like the way your face looks or feels after using such a product. This also goes for facials. They are not particularly harmful, although in some cases acne can flare in a delayed fashion following a facial. A facial treatment does not "clean out" the keratin plug described earlier.
THE HORMONAL CONTRIBUTION
Hormones do indeed affect sebum production, so there may be benefit for women who take oral
contraceptives that are predominantly estrogenic. For a few the benefit is unmistakable. For the majority the benefit is modest. For theoretical reasons, some oral contraceptive pills, such as Ortho-Tri-Cyclen, Yasmin and Yaz are preferred for acne sufferers. However, no one has been able to predict which one works best and how you will respond to the pill. Typically it takes two to four months to see the therapeutic benefits from the oral contraceptive pill.
ACNE THERAPIES
Step one therapy for acne has traditionally comprised tretinoin (Retin-A). The rationale for using this vitamin-A derivative is simple: It is comedolytic. It thins the outer layer of skin (the stratum corneum), and slowly over months reverses the formation of the keratin-sebum plugs, which lead to rupture of the sebaceous follicle. That is the good news. The bad news is that it is generally irritating to all but the toughest oilier skin. Newer preparations, such as Avita Cream and Retin-A Micro Gel, seem to be better tolerated but are more expensive. Furthermore, a persistent red flush is seen in many patients on Retin-A. Certain areas of the face, such as the chin, are easily irritated with tretinoin and the frequency of use might be limited to every two or three days until your skin gets used to it. Tretinoin cream can be diluted half-and-half with a moisturizer, such as Eucerin cream. Excess Washing tends to make tretinoin therapy more irritating. It is also frequently forgotten that it may takes months before you see the full benefit of tretinoin.
If you are old enough to read this article you have had first-hand experience with acne. What follows is a rational approach to the treatment of acne. Defined terms are italicized and can be found in Table I. Acne is an all-encompassing term for skin blemishes, on the face, chest, and back. The location of acne directly corresponds to areas where sebaceous follicles are found in high density. The battleground of acne is within the sebaceous follicle, which is basically a hair follicle with attached oil glands. However, the hair is often absent or underdeveloped. The gland produces oil which is called sebum. Androgens (masculinizing hormones produced by both men and women) increase sebum production markedly. It is no coincidence that
acne begins at puberty when sebum production accelerates in response to hormonal changes.
Sebaceous oil would not be a problem if it flowed freely onto the surface as it does on the scalp. However, a second key event in the formation of acne occurs; this event is the formation of an oil-duct plug, known as a microcomedone. Cells lining the duct of the sebaceous follicle peel off the side and combine with the oil to form a tight little plug. Behind this plug acne bacteria proliferate, metabolize the sebum, and create an inflammatory reaction. Rupture of the plugged gland causes the classic pustule (known as a "zit"), and occasionally, if the reaction is more vigorous, larger papules and nodules. So it takes three elements--sebum, a plug, and the ensuing proliferation of acne bacteria--to create acne lesions. Treatment of acne is predicated
on the elimination of one or more of these pathogenic elements.
THE "DIRT" MYTH
Since acne is not due to dirt, excess washing will not be beneficial. You cannot scrub away what is under the skin, and scouring your face usually makes acne worse rather than better. Washing once or twice a day with a mild soap is okay--just do not overdo it.
THE "DIET' MYTH
Although sebum is an oil, it is not produced in excess by dietary intake of various fats such as chocolate or French fries. Dietary restrictions, while good for your arteries, will not alter acne problems. The oil that causes a problem with acne is not on the face. Drying the oil off your face using astringents (drying agents) will not eliminate acne, although you might like the way your face looks or feels after using such a product. This also goes for facials. They are not particularly harmful, although in some cases acne can flare in a delayed fashion following a facial. A facial treatment does not "clean out" the keratin plug described earlier.
THE HORMONAL CONTRIBUTION
Hormones do indeed affect sebum production, so there may be benefit for women who take oral
contraceptives that are predominantly estrogenic. For a few the benefit is unmistakable. For the majority the benefit is modest. For theoretical reasons, some oral contraceptive pills, such as Ortho-Tri-Cyclen, Yasmin and Yaz are preferred for acne sufferers. However, no one has been able to predict which one works best and how you will respond to the pill. Typically it takes two to four months to see the therapeutic benefits from the oral contraceptive pill.
ACNE THERAPIES
Step one therapy for acne has traditionally comprised tretinoin (Retin-A). The rationale for using this vitamin-A derivative is simple: It is comedolytic. It thins the outer layer of skin (the stratum corneum), and slowly over months reverses the formation of the keratin-sebum plugs, which lead to rupture of the sebaceous follicle. That is the good news. The bad news is that it is generally irritating to all but the toughest oilier skin. Newer preparations, such as Avita Cream and Retin-A Micro Gel, seem to be better tolerated but are more expensive. Furthermore, a persistent red flush is seen in many patients on Retin-A. Certain areas of the face, such as the chin, are easily irritated with tretinoin and the frequency of use might be limited to every two or three days until your skin gets used to it. Tretinoin cream can be diluted half-and-half with a moisturizer, such as Eucerin cream. Excess Washing tends to make tretinoin therapy more irritating. It is also frequently forgotten that it may takes months before you see the full benefit of tretinoin.
Step two therapy for mild to moderate acne with simple pimples (known as pustules) and small red bumps (known as acne papules) usually means adding an anti-inflammatory medication to the regimen. The OTC benzoyl peroxides are such medications. Benzoyl peroxide in 2.5%, 5%, and 10% seem to be equally effective, but the 10% is more drying and irritating than the 2.5%. We recommend the 5% lotion used once or twice a day. Benzoyl peroxide works as an antibiotic, suppressing acne bacteria. The drying and peeling effec may seem therapeutic, but it is a side effect. Benzoyl peroxide should NEVER be used at the same time as Retin-A products because it will neutralize the benefit of the Retin-A. Practically this means that you apply the benzoyl peroxide in the morning and the Retin-A before bed. Other useful antibiotic (anti-inflammatory) solutions/lotions include erythromycin, sulfur preparations, and clindamycin (Cleocin-T). These are less irritating but more expensive than benzoyl peroxide. Also, if you have sensitive skin you may need to use a lotion form of the antibiotic. For very sensitive skin, topical sulfur based antibiotics such as sulfacetamide (Klaron, Sulfacet R, etc.) may be the least irritating.
If your acne is more severe, including painful lumps, or if you do not respond to medicines applied on the skin (topical medications), the next step is to consider oral antibiotics. These are especially useful for individuals with severe back acne, which is hard to treat with topical products. Oral antibiotics like tetracycline, doxycycline, minocycline, erythromycin, and Septra (sulfamethoxazole-trimethoprim), all have a place in the treatment of the more severe grades of acne. It takes up to 6-8 weeks to see the full benefit of oral antibiotics. Unfortunately the benefits rarely persist if oral antibiotics are stopped. Some individuals initially improve over
months, only to relapse with severe acne. When this type of resistance, or tolerance, is seen, we often switch to different antibiotics or stop them for a while. The most common side effect of antibiotics is usually some form of stomach discomfort in perhaps 10% to 20% of people, and they will need to try something different. About one in ten to one in twenty women will develop a vaginal yeast infection if they are on prolonged antibiotic therapy. Also allergic rashes can occur to antibiotics, particularly with Septra. If this happens with any antibiotic it should be stopped and reported to your provider immediately. Minocycline (Minocin) can be effective for severe acne and has some peculiar side effects: Occasionally it causes dizziness, darkening of the skin or nails, and very rarely, graying of the teeth.
months, only to relapse with severe acne. When this type of resistance, or tolerance, is seen, we often switch to different antibiotics or stop them for a while. The most common side effect of antibiotics is usually some form of stomach discomfort in perhaps 10% to 20% of people, and they will need to try something different. About one in ten to one in twenty women will develop a vaginal yeast infection if they are on prolonged antibiotic therapy. Also allergic rashes can occur to antibiotics, particularly with Septra. If this happens with any antibiotic it should be stopped and reported to your provider immediately. Minocycline (Minocin) can be effective for severe acne and has some peculiar side effects: Occasionally it causes dizziness, darkening of the skin or nails, and very rarely, graying of the teeth.
Below is a ranking of oral antibiotics and a few comments.
1. Minocycline is taken once a day with food.
2. Septra (also known as sulfamethoxazole trimethoprim generically) is cheap and causes the most allergic reactions, but is often effective when other drugs fail.
3. Doxycycline is inexpensive but must be taken with food to minimize indigestion.
4. Erythromycin is very safe (even in pregnancy) but stomach problems are common.
5. Tetracycline is safe and inexpensive, but must be taken on an empty stomach.
NEWER TOPICAL PREPARATIONS
1. Azelex and Finacea are azelaic acid which is a naturally-produced organic acids that has antibiotic properties and some benefit in reducing keratin plug formation. A touted benefit is that it gradually diminishes acne blemishes over three to six months.
1. Azelex and Finacea are azelaic acid which is a naturally-produced organic acids that has antibiotic properties and some benefit in reducing keratin plug formation. A touted benefit is that it gradually diminishes acne blemishes over three to six months.
2. Differin cream/gel, also known as adapalene, is a new vitamin-A-like product which seems to be about as effective or slightly more effective than Retin-A, but it may be less irritating.
3. Tazorac cream/gel is an agent that works similar to tretinoin (Retin A).
4. Salicylic acid (a beta hydroxy acid) can be found in products such as Neutrogena acne pore treatment. Beta-hydroxy acids and Alpha-hydroxy acids, such as glycolic acid or lactic acid, are widely available in drug stores, and may be useful for mild acne. A program that combines several different topicals that we have discussed is Proactive. The alpha and beta hydroxy acids are keratolytic acids which have a peeling effect on the skin. They unseat some blackheads and whiteheads, but can be irritating to sensitive skin. They can be used in combination with other drugs like topical erythromycin or clindamycin. I do not usually use these with retinoids, such as Retin-A or Avita, because the combination is particularly irritating.
3. Tazorac cream/gel is an agent that works similar to tretinoin (Retin A).
4. Salicylic acid (a beta hydroxy acid) can be found in products such as Neutrogena acne pore treatment. Beta-hydroxy acids and Alpha-hydroxy acids, such as glycolic acid or lactic acid, are widely available in drug stores, and may be useful for mild acne. A program that combines several different topicals that we have discussed is Proactive. The alpha and beta hydroxy acids are keratolytic acids which have a peeling effect on the skin. They unseat some blackheads and whiteheads, but can be irritating to sensitive skin. They can be used in combination with other drugs like topical erythromycin or clindamycin. I do not usually use these with retinoids, such as Retin-A or Avita, because the combination is particularly irritating.
ANSWERS TO FREQUENTLY-ASKED QUESTIONS
Is there an important antibiotic/birth control pill interaction?
Most of the commonly-used oral antibiotics (for example, tetracycline, erythromycin, Septra, minocycline) do not negate the birth control effect of oral contraceptives, although the Physician's Desk Reference (PDR) makes statements to the contrary. There are some theoretical reasons why the oral contraceptive effectiveness might be reduced, but when this has been studied, oral contraceptive failure when antibiotics areused at the same time is extremely rare. Of course, using a backup method can eliminate any concern and has its own benefits. There is a large literature base on this particular subject and you should discuss it further with your practitioner.
Can I change my pores?
Your pore size is inherited and cannot be changed permanently by acne medicines. However, physical treatments such as deep peels, surgery, and laser treatment may smooth the skin surface and make pores less noticeable.
What do we do for the really bad (scarring) acne that responds poorly, if at all, to oral antibiotics?
The remedy for this group of patients is Accutane (isotretinoin). A typical candidate for this includes someone who has tried topicals and at least one or two different oral antibiotics without success. There are individuals who are physically and emotionally scarred by their acne, and they should be afforded a potential cure. Accutane in long-term studies seems to cure 60%-80% of severe acne types. Typically, it is used for sixteen to twenty weeks and may be repeated two or three times. It may fail to provide lasting benefit to teenagers and they may need one or two additional courses years later. Also, it fails more often in those with very severe
back acne. A separate detailed account of the side effects associated with this medication can be found under "Accutane" in the Skin Problem List.
CONCLUSION
If you have been able to wade through this discussion of acne, you realize there is a logic to the various
treatments. Depending on your skin type and grade of acne, we can help you choose a regimen that will work
for you. One area that was not discussed under "Acne" but is discussed further under "Scars" is what to do
about acne blemishes, marks, and scars.
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