Antiacne Drugs

Definition

Antiacne drugs are medicines that help clear up pimples, blackheads, whiteheads, and more severe forms of acne.

Purpose

Different types of antiacne drugs are used for different purposes. For example, lotions, soaps, gels, and creams containing benzoyl peroxide or tretinoin may be used to clear up mild to moderately severe acne. Isotretinoin (Accutane) is prescribed only for very severe, disfiguring acne.Acne is a skin condition that occurs when pores or hair follicles become blocked. This blockage allows a waxy material called sebum to collect inside the pores or follicles. Normally, sebum flows out onto the skin and hair to form a protective coating, but when it cannot get out, small swellings develop on the skin surface. Bacteria and dead skin cells can also collect that can cause inflammation. Swellings that are small and not inflamed are whiteheads or blackheads. When they become inflamed, they turn into pimples. Pimples that fill with pus are called pustules.

Anti-Acne Drugs
Brand Name (Generic Name)	Possible Common Side Effects Include:
Accutane (isotretinoin)	Dry skin, dry mouth, conjunctivitis
Benzamycin	Dry and itchy skin
Cleocin T(clindamycin phosphate)	Dry skin
Desquam-E(benzoyl peroxide)	Itching, red and peeling skin
Erythromycin topical (A/T/S, erycette, t-stat)	Burning, dry skin, hives, red and peeling skin
Minocin (minocycline hydrochloride)	Headache, hives, diarrhea, peeling skin, vomiting
Retin-A (tretinoin)	Darkening of the skin, blistering, crusted, or puffy skin

The severity of acne is often influenced by seasonal changes; it is typically less severe in summer than in winter. In addition, acne in girls is often affected by the menstrual cycle.Acne cannot be cured, but acne drugs can help clear the skin. Benzoyl peroxide and tretinoin work by mildly irritating the skin. This encourages skin cells to slough off, which helps open blocked pores. Benzoyl peroxide also kills bacteria, which helps prevent whiteheads and blackheads from turning into pimples. Isotretinoin shrinks the glands that produce sebum.

Description

Benzoyl peroxide is found in many over-the-counter acne products that are applied to the skin, such as Benoxyl, Clear By Design, Neutrogena Acne, PanOxyl, and some formulations of Clean & Clear, Clearasil, and Oxy. Some benzoyl peroxide products are available without a physician's prescription; others require a prescription. Tretinoin (Retin-A) is available only with a physician's prescription and comes in liquid, cream, and gel forms, which are applied to the skin. Isotretinoin (Accutane), which is taken by mouth in capsule form, is available only with a physician's prescription. Only physicians who have experience in diagnosing and treating severe acne, such as dermatologists, should prescribe isotretinoin.Some newer antiacne preparations combine benzoyl peroxide with antibiotics. One combination of benzoyl peroxide with clindamycin is sold under the trade name BenzaClin.Many antiacne preparations contain compounds derived from plants that have anti-inflammatory properties. One group of researchers listed thirtyeight different plants that are beneficial in treating acne and other inflammatory skin conditions.

Recommended dosage

The recommended dosage depends on the type of antiacne drug. These drugs usually come with written directions for patients and should be used only as directed. Patients who have questions about how to use the medicine should check with a physician or pharmacist.

Key terms

Acne — A skin condition in which raised bumps, pimples, and cysts form on the face, neck, shoulders and upper back.Bacteria — Tiny, one-celled forms of life that cause many diseases and infections.Bowel — The intestine; a tube-like structure that extends from the stomach to the anus. Some digestive processes are carried out in the bowel before food passes out of the body as waste.Cyst — An abnormal sac or enclosed cavity in the body, filled with liquid or partially solid material.Dermatologist — A doctor who specializes in treating diseases and disorders of the skin.Eczema — Inflammation of the skin with itching and a rash. The rash may have blisters that ooze and form crusts.Pimple — A small, red swelling of the skin.Psoriasis — A skin disease in which people have itchy, scaly, red patches on the skin.Pus — Thick, whitish or yellowish fluid that forms in infected tissue.Triglyceride — A substance formed in the body from fat in the diet.Patients who use isotretinoin usually take the medicine for a few months, then stop for at least two months. Their acne may continue to improve even after they stop taking the medicine. If the condition is still severe after several months of treatment and a two-month break, the physician may prescribe a second course of treatment.

Precautions

Isotretinoin

Isotretinoin can cause serious birth defects, including mental retardation and physical deformities. This medicine should not be used during pregnancy. Women who are able to bear children should not use isotretinoin unless they have very severe acne that has not cleared up with the use of other antiacne drugs. In that case, a woman who uses this drug must have a pregnancy test two weeks before beginning treatment and each month they are taking the drug. Another pregnancy test must be done one month after treatment ends. The woman must use an effective birth control method for one month before treatment begins and must continue using it throughout treatment and for one month after treatment ends. Women who are able to bear children and who want to use this medicine should discuss this information with their health care providers. Before using the medicine, they will be asked to sign a consent form stating that they understand the danger of taking isotretinoin during pregnancy and that they agree to use effective birth control.Do not donate blood to a blood bank while taking isotretinoin or for 30 days after treatment with the drug ends. This will help reduce the chance of a pregnant woman receiving blood containing isotretinoin, which could cause birth defects.Isotretinoin may cause a sudden decrease in night vision. If this happens, do not drive or do anything else that could be dangerous until vision returns to normal. Let the physician know about the problem.This medicine may also make the eyes, nose, and mouth dry. Ask the physician about using special eye drops to relieve eye dryness. To temporarily relieve the dry mouth, chew sugarless gum, suck on sugarless candy or ice chips, or use saliva substitutes, which come in liquid and tablet forms and are available without a prescription. If the problem continues for more than two weeks, check with a physician or dentist. Mouth dryness that continues over a long time may contribute to tooth decay and other dental problems.Isotretinoin may increase sensitivity to sunlight. Patients being treated with this medicine should avoid exposure to the sun and should not use tanning beds, tanning booths, or sunlamps until they know how the drug affects them.In the early stages of treatment with isotretinoin, some people's acne seems to get worse before it starts getting better. If the condition becomes much worse or if the skin is very irritated, check with the physician who prescribed the medicine.

Benzoyl peroxide and tretinoin

When applying antiacne drugs to the skin, be careful not to get the medicine in the eyes, mouth, or inside of the nose. Do not put the medicine on skin that is wind burned, sunburned, or irritated, and do not apply it to open wounds.Because such antiacne drugs as benzoyl peroxide and tretinoin irritate the skin slightly, avoid doing anything that might cause further irritation. Wash the face with mild soap and water only two or three times a day, unless the physician says to wash it more often. Avoid using abrasive soaps or cleansers and products that might dry the skin or make it peel, such as medicated cosmetics, cleansers that contain alcohol, or other acne products that contain resorcinol, sulfur or salicylic acid.If benzoyl peroxide or tretinoin make the skin too red or too dry or cause too much peeling, check with a physician. Using the medicine less often or using a weaker strength may be necessary.Tretinoin may increase sensitivity to sunlight. While being treated with this medicine, avoid exposure to the sun and do not use tanning beds, tanning booths, or sunlamps. If it is not possible to avoid being in the sun, use a sunscreen with a skin protection factor (SPF) of at least 15 or wear protective clothing over the treated areas. The skin may also become more sensitive to cold and wind. People who use this medicine should protect their skin from cold and wind until they know how the medicine affects them.Benzoyl peroxide may discolor hair or colored fabrics.

Special conditions

People who have certain medical conditions or who are taking certain other medicines may have problems if they use antiacne drugs. Before using these products, be sure to let the physician know about any of these conditions:ALLERGIES. Anyone who has had unusual reactions to etretinate, isotretinoin, tretinoin, vitamin A preparations, or benzoyl peroxide in the past should let his or her physician know before using an antiacne drug. The physician should also be told about any allergies to foods, dyes, preservatives, or other substances.PREGNANCY. Women who are pregnant or who may become pregnant should check with a physician before using tretinoin or benzoyl peroxide. Isotretinoin causes birth defects in humans and must not be used during pregnancy.BREASTFEEDING. No problems have been reported in nursing babies whose mothers used tretinoin or benzoyl peroxide. Women who are breastfeeding babies should not take isotretinoin, however, as it may cause problems in nursing babies.OTHER MEDICAL CONDITIONS. Before using antiacne drugs applied to the skin, people with any of these medical problems should make sure their physicians are aware of their conditions:

eczema. Antiacne drugs that are applied to the skin may make this condition worse.
sunburn or raw skin. Antiacne drugs that are applied to the skin may increase the pain and irritation of these conditions.

In people with certain medical conditions, isotretinoin may increase the amount of triglyceride (a fatty-substance) in the blood. This may lead to heart or blood vessel problems. Before using isotretinoin, people with any of these medical problems should make sure their physicians are aware of their conditions:

alcoholism or heavy drinking, now or in the past
diabetes (or family history of diabetes). Isotretinoin may also change blood sugar levels.
family history of high triglyceride levels in the blood
severe weight problems.

USE OF CERTAIN MEDICINES. Using antiacne drugs with certain other drugs may affect the way the drugs work or may increase the chance of side effects.

Side effects

Isotretinoin

Minor discomforts such as dry mouth or nose, dry eyes, dry skin, or itching usually go away as the body adjusts to the drug and do not require medical attention unless they continue or are bothersome.Other side effects should be brought to a physicians attention. These include:

burning, redness, or itching of the eyes
nosebleeds
signs of inflammation of the lips, such as peeling, burning, redness or pain

Bowel inflammation is not a common side effect, but it may occur. If any of the following signs of bowel inflammation occur, stop taking isotretinoin immediately and check with a physician:

pain in the abdomen
bleeding from the rectum
severe diarrhea

Benzoyl peroxide and tretinoin

The most common side effects of antiacne drugs applied to the skin are slight redness, dryness, peeling, and stinging, and a warm feeling to the skin. These problems usually go away as the body adjusts to the drug and do not require medical treatment.Other side effects should be brought to a physician's attention. Check with a physician as soon as possible if any of the following side effects occur:

blistering, crusting or swelling of the skin
severe burning or redness of the skin
darkening or lightening of the skin. (This effect will eventually go away after treatment with an antiacne drug ends.)
skin rash

Other side effects are possible with any type of antiacne drug. Anyone who has unusual symptoms while using antiacne drugs should get in touch with his or her physician.

Interactions

Patients using antiacne drugs on their skin should tell their physicians if they are using any other prescription or nonprescription (over-the-counter) medicine that they apply to the skin in the same area.Isotretinoin may interact with other medicines. When this happens, the effects of one or both drugs may change or the risk of side effects may be greater. Anyone who takes isotretinoin should let the physician know about all other medicines he or she is taking and should ask whether the possible interactions can interfere with drug therapy. Among the drugs that may interact with isotretinoin are:

etretinate (Tegison), used to treat severe psoriasis. Using this medicine with isotretinoin increases side effects.
tretinoin (Retin-A, Renova). Using this medicine with isotretinoin increases side effects.

vitamin A or any medicine containing vitamin A. Using any vitamin A preparations with isotretinoin increases side effects. Do not take vitamin supplements containing vitamin A while taking isotretinoin.
tetracyclines (used to treat infections). Using these medicines with isotretinoin increases the chance of swelling of the brain. Make sure the physician knows if tetracycline is being used to treat acne or another infection.

Resources

Books

Beers, Mark H., MD, and Robert Berkow, MD., editors. "Acne." Section 10, Chapter 116 In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2002.Beers, Mark H., MD, and Robert Berkow, MD., editors. "Warts (Verrucae)." Section 10, Chapter 115 In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2002.Wilson, Billie Ann, Margaret T. Shannon, and Carolyn L. Stang. Nurse's Drug Guide 2003. Upper Saddle River, NJ: Prentice Hall, 2003.

Periodicals

Breneman, D., R. Savin, C. Van dePol, et al. "Double-Blind, Randomized, Vehicle-Controlled Clinical Trial of Once-Daily Benzoyl Peroxide/Clindamycin Topical Gel in the Treatment of Patients with Moderate to Severe Rosacea." International Journal of Dermatology 43 (May 2004): 381-387.Darshan, S., and R. Doreswamy. "Patented Antiinflammatory Plant Drug Development from Traditional Medicine." Phytotherapy Research 18 (May 2004): 343-357.Halder, R. M., and G. M. Richards. "Topical Agents Used in the Management of Hyperpigmentation." Skin Therapy Letter 9 (June-July 2004): 1-3.Kligman, D. E., and Z. D. Draelos. "High-Strength Tretinoin for Rapid Retinization of Photoaged Facial Skin." Dermatologic Surgery 30 (June 2004): 864-866.Leyden, J. J., D. Thiboutot, and A. Shalita. "Photographic Review of Results from a Clinical Study Comparing Benzoyl Peroxide 5%/Clindamycin 1% Topical Gel with Vehicle in the Treatment of Rosacea." Cutis 73, Supplement 6 (June 2004): 11-17.

Organizations

American Academy of Dermatology (AAD). P. O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. http://www.aad.org..American Society of Health-System Pharmacists (ASHP). 7272 Wisconsin Avenue, Bethesda, MD 20814. (301) 657-3000. http://www.ashp.org.United States Food and Drug Administration (FDA). 5600 Fishers Lane, Rockville, MD 20857-0001. (888) INFO-FDA. http://www.fda.gov.