Terbinafine is an antifungal medication that fights infections caused by fungus.

Lamisil AT (for the skin) is used to treat skin infections such as athlete's foot, jock itch, and ringworm infections.

Lamisil AT may also be used for purposes not listed in this medication guide.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Do not take by mouth. Lamisil AT is for use only on the skin. Do not use this medicine to treat fungal infections of your fingernails, toenails, or scalp.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

Wash your hands before and after using this medicine.

Clean and dry the affected area. Apply the medicine as directed.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared.

Call your doctor if your symptoms do not improve, or if they get worse.

Do not cover the treated skin area unless your doctor tells you to.

Store at room temperature away from moisture and heat. Keep the medicine container tightly closed when not in use.

You should not use Lamisil AT if you are allergic to it.

Lamisil AT is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether terbinafine passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Terbinafine is not approved for use by anyone younger than 12 years old.

Apply the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next dose. Do not use extra medicine to make up the missed dose.

An overdose of terbinafine is not expected to be dangerous. Seek emergency medical attention or call the Poison Help line at 1-800-222-1222 if anyone has accidentally swallowed the medication.

If Lamisil AT gets in your eyes, nose, mouth, rectum, or vagina, rinse with water.

Avoid using other medications on the areas you treat with terbinafine unless your doctor tells you to.

Avoid wearing tight-fitting, synthetic clothing that doesn't allow air circulation. Wear loose-fitting clothing made of cotton and other natural fibers until your infection is healed.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Terbinafine may cause serious side effects. Stop using terbinafine and call your doctor at once if you have:

• severe blistering, itching, redness, peeling, dryness, or irritation of treated skin.

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.