What Causes Acne?
Acne begins when the pores in the skin become clogged and can no longer drain sebum (an oil made by the sebaceous glands that protects and moisturizes the skin.) The sebum build-up causes the surrounding hair follicle to swell.
Hair follicles swollen with sebum are called comedones. If the sebum stays beneath the skin, the comedones
produce white bumps called whiteheads. If the sebum reaches the surface of the skin, the comedones produce
darkened bumps called blackheads. This black discoloration is due to sebum darkening when it is exposed to
air. It is not due to dirt. Both whiteheads and blackheads may stay in the skin for a long time.
Bacteria called Propionibacterium acnes (P. acnes) that normally live on the top of the skin can enter the clogged pores and infect the sebum. This causes the skin to become swollen, red, and painful.
Infected sebaceous glands may burst, releasing sebum and bacteria into the surrounding skin, creating additional inflammation. In severe cases, larger nodules and cysts may form in the deeper layers of the skin.
What Are the Different Types of Acne?
Acne can be categorized by its severity:
- Mild acne describes a few scattered comedones (whiteheads or blackheads) with minimal inflammation (no pustules).
- Moderate acne describes a denser collection of comedones as well as red, inflamed, pus-filled lesions (pustules).
- Severe acne, also called nodular or cystic acne, describes widespread and deep lesions that are painful, inflamed, and red. This form of acne is likely to lead to scarring if left untreated.
Mild acne with comedones on the forehead Moderate acne with pustules
Who Gets Acne?
Anyone can get acne, but it appears most often in teenagers, whose surging levels of androgen (a type of hormone) create larger and more active sebaceous glands. Acne may continue for people in their twenties and thirties, and even women over forty. Acne also appears more commonly in people whose parents had acne.
What Factors Make Acne Worse?
Acne lesions can come and go. These factors can cause acne to flare:
- Changing hormone levels in women 2 to 7 days before their menstrual period, during pregnancy, or when starting or stopping birth control pills
- Oil from skin products (moisturizers or cosmetics) or grease in the workplace (for example, a kitchen with fry vats)
- Pressure from sports helmets or equipment, backpacks, tight collars, or tight uniforms
- Environmental irritants, such as pollution and high humidity
- Squeezing or picking at blemishes
- Hard scrubbing of the skin
What Are The Treatment Options for Acne?
Almost all cases of acne can be effectively treated. Treatment goals
are to heal existing lesions, stop new lesions from forming, and prevent scarring.
Acne treatments aim to control one or more of the underlying causes of acne. For instance, topical retinoids, such as Differin or Retin A Micro, may help unclog sebaceous glands and keep pores open. Antibiotics may be used to fight the P. acnes bacteria. Accutane or hormonal agents, such as birth control pills, may be used to reduce sebum (oil) production.
Before Treatment After Treatment
A. Topical medications (applied to the skin)
Over the counter
- Benzoyl peroxide—This is found in many products including Clearasil and Proactiv. It is a mild antibiotic that kills the P. acnes bacteria. It is available in different concentrations. Higher concentrations are more likely to irritate the skin. It does not unclog blocked pores so is not as helpful for reducing whiteheads and blackheads.
- Sulfur and salicylic acid—These have some mild ability to break down whiteheads and blackheads.
- Topical retinoids (Differin, Retin A Micro, Tazorac, tretinoin)—These are among the most effective and commonly used acne medications. Topical retinoids are unique in their ability to unclog swollen pores. They may be used alone for mild acne or combined with other medications for moderate-to-severe acne. They may also be recommended for long-term use, even after the acne is under control, to keep the skin clear.
- Topical antibiotics—Antibiotics applied to the skin, such as clindamycin (Clindagel) and erythromycin, kill the P. acnes bacteria that leads to inflammation.
B. Oral medications (taken by mouth)
- Oral antibiotics—These medications, which include tetracycline, doxycycline (Adoxa, Doryx), and minocycline (Dynacin, Solodyn), act systemically and can reach bacteria in the deep layers of the dermis. They are also used for their anti-inflammatory effects.
- Oral contraceptives (Ortho Tri-Cyclen, Yaz)—For women who experience hormonally triggered acne, birth control pills may be prescribed to reduce sebum production.
- Anti-androgen drugs—Some drugs used for other medical conditions are known to reduce androgen levels, such as spironolactone (Aldactone). These may be used in some cases of acne.
- Isotretinoin (Accutane, Sotret)—Isotretinoin remains the most effective treatment for severe acne or acne that does not respond to other treatments. Isotretinoin treats all causes of acne: excess sebum, clogged pores, bacterial overgrowth, and inflammation. Most patients take the medicine for 15-to-20-week periods that may be repeated if necessary. Treatment requires monthly office visits, monthly lab tests, and strict contraception. It is critical that women of child-bearing age do not get pregnant while taking isotretinoin because of the serious risk of birth defects. The iPledge program was developed to reduce the likelihood of birth defects and other side effects.
Many of these medications have side effects, such as burning, redness, and irritation. With some medicines, such as topical retinoids, these side effects usually decrease or go away after the medicine is used for a period of time. If side effects are severe or don't go away, tell your doctor.
For persistent lesions that are inflamed or unresponsive to medications, some doctors recommend additional methods, including extraction, light therapy, or corticosteroid injections.
How Will I Choose a Treatment Plan?
Your doctor will recommend a treatment based on these factors:
- Severity of your acne. Mild acne may respond well to a topical retinoid alone. Moderate acne may respond better to a combination of topical retinoid with an antibiotic or other medication. Severe acne with scarring may need treatment with an oral retinoid (Accutane, Sotret).
- Results of previous treatments. Medications may be added in a step-wise fashion, only if previous treatments are found to be ineffective.
- Degree of scarring. More aggressive therapies may be started earlier if acne scars have already started developing.
- Gender. Some treatments are available only for females, such as birth control pills.
Whatever your treatment plan, it is important that you give it enough time to work. This may mean waiting 6 to 8 weeks to see results. While the older acne lesions are healing, the medication is hard at work keeping new lesions from forming. Staying on your medication is the most important step to getting acne under control.
How Can I Keep My Acne Under Control?
After your acne clears, your doctor may recommend that you continue therapy with a topical retinoid to keep it under control. It is always a good idea to maintain good skin care and use skin care products labeled as “non-comedogenic” (do not promote acne)
What About Self Care and Prevention?
For ongoing self-care and prevention of acne, follow a few simple guidelines:
- Clean skin gently—Use a mild skin cleanser twice a day, and pat skin dry. Harsh cleansers and astringents can actually worsen acne.
- Do not pop, squeeze, or pick at acne lesions, as this can promote inflammation and infection. Keep hands away from your face and other acne-prone parts of the skin.
- Limit sun exposure—Tanning only masks acne at best. At worst, sun exposure can lead to skin damage, especially if you are using an acne treatment that makes your skin more sensitive to sunlight and UV rays (this includes tanning booths).
- Choose cosmetics with care—As mentioned above, choose non-greasy skin products, and look for words like “non-comedogenic”, “oil-free”, and “water-based”. Some facial products contain active acne-fighting ingredients, such as benzoyl peroxide or salicylic acid, to help keep mild acne at bay.
- Be patient with your treatment—Find out how much time it should take for your acne treatment to work (generally 6-8 weeks) and then stick with it. Stopping treatment early may prevent you from seeing good results or even cause a relapse of symptoms. Your skin may look worse before it begins to improve. You may need to try more than one type of treatment.
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This information is for general educational
uses only. It may not apply to you and your specific medical needs. This information should not be used in place of a visit,
call, consultation with or the advice of your physician or health care professional. Communicate promptly with your physician
or other health care professional with any health-related questions or concerns.
Be sure to follow specific instructions given to you by your physician or health care professional.