Definition

Topical antifungal drugs are medicines applied to the skin to treat skin infections in various parts of the body caused by a fungus.

Purpose

Topical antifungal agents are applied locally to the skin, nail, armpits, mouth, groin, and genital areas, including scalp, neck, trunk, and other parts of the body, to treat fungal infections. They kill or inactivate fungi and yeast. Many topical antifungal drugs are available without a physician’s prescription and come in many forms, including creams, ointments, liquids, powders, aerosol sprays, shampoo and vaginal suppositories. Creams and liquids are usually the most effective for treating fungal infections on the skin, because they can get into the cracks and crevices where fungi grow. But because powders absorb moisture, they are good to use in moist areas of the body, such as between the toes.

Topical antifungal drugs not only relieve the symptoms of fungal infection, such as itching, burning, and cracked skin, but they also eliminate the fungus. However, those that occur inside the body or that do not clear up after treatment with creams or ointments may need to be treated with systemic antifungal drugs.

Description

There are a large number of drugs currently available in topical form for fungal infections. Other than imidazoles, (miconazole, clotrimazole, econazole, ketonazole, oxiconazole, sulconazole and the allylamine derivatives (butenafine, naftifine, terbinafine, the drugs in this therapeutic class are chemically distinct from each other. All drugs when applied topically have a good margin of safety, and most show a high degree of effectiveness. There are no studies comparing drugs on which to case a recommendation for drugs of choice. Although some of the topical antifungals are available over-the-counter, they may be as effective as prescription drugs for this purpose.

Traditional older antifungal drugs such as undecylinic acid and gentian violet (also known as crystal violet) remain available, but have a lower cure rate (complete eradication of fungus) than the newer agents and are not recommended. Tolnaftate has a lower cure rate than the newer drugs, but may be used prophylactically to prevent infection.

Recommended Dosage

All drugs are applied topically. Consult individual product information for specific application recommendations. As with all topical products, selection of the dosage form may be as important as proper drug selection. Consider factors such as presence or absence of hair on the affected area, and type of skin to which the medication is to be applied. Thin liquids may preferable for application to hairy areas, creams for the hands and face, and ointments may be preferable for the trunk and legs. Other dosage forms available include shampoos and sprays. Ciclopirox and triacetin are available in formulations for topical treatment of nail fungus as well as skin infections. Most topical antifungal drugs require four weeks of treatment. Infections in some areas, particularly the spaces between toes, may take up to six weeks for cure.

How to use this medicine

This medicine is for external use only. Do not take by mouth. Follow the directions on the prescription label. Wash your hands before and after use. If treating hand or nail infections, wash hands before use only. Apply enough product to cover the affected skin or nail and surrounding area. Do not cover the treated area with a bandage or dressing unless your doctor or health care professional tells you to. Do not get this medicine into your eyes. If you do, rinse out with plenty of cool tap water. Use this medicine at regular intervals. Do not use more often than directed. Finish the full course prescribed even if you are better. Do not skip doses or stop using this medicine early.

The creams are applied to the affected area twice daily for two to four weeks, including a margin of several centimeters of normal skin. Continue for one or two weeks after the last visible rash has cleared. Repeated treatment is often necessary. Available topical antifungal as below:

Using with other medication

Interactions are not expected. Do not use any other skin products on the affected area without telling your doctor or health care professional. This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

While using this medicine

Things you should do:

• Tell your doctor or health care professional if your symptoms do not improve after 1 week. Some fungal infections can take a long time to be cured.
• Be sure to finish your full course of treatment.
• After bathing, make sure to dry your skin completely. Most types of fungus live in moist environments. Wear clean socks and clothing every day.

Side effects

Side effects that you should report to your doctor or health care professional as soon as possible:

• Skin rash, itching
• Blistering, increased redness, peeling, or swelling of the skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

• Dry skin.
• Minor skin irritation, burning or stinging

Precautions

Most topical antifungal agents are well tolerated. The most common adverse effects are localized irritation caused by the vehicle or its components. This may include redness, itch, and a burning sensation. Some direct allergic reactions are possible. Topical antifungal drugs should only be applied in accordance with labeled uses. They are not intended for ophthalmic (eye) or otic (ear) use. Application to mucous membranes should be limited to appropriate formulations.

The antifungal drugs have not been evaluated for safety in pregnancy and lactation on topical application under the pregnancy risk category system. Although systemic absorption is probably low, review specific references. Gentian violet is labeled with a warning against use in pregnancy.