Terbinafine is used to treat certain types of fungal infections (for example, of the fingernail or toenail). It works by stopping the growth of fungus. This medication belongs to a class of drugs known as antifungals.

Read the Medication Guide provided by your pharmacist before you start taking terbinafine and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually once a day. The dosage and length of treatment is based on your medical condition and response to treatment.

It may take several months after you finish treatment to see the full benefit of this drug. It takes time for your new healthy nails to grow out and replace the infected nails.

Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection.

Tell your doctor if your condition lasts or gets worse.

Diarrhea or stomach upset may occur. If either of these effects lasts or gets worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Changes in your sense of taste/smell or loss of taste/smell may occur. These side effects may improve after stopping terbinafine, but can last for a long time or become permanent. Tell your doctor right away if you notice either of these side effects.

Tell your doctor right away if you have any serious side effects, including:

• vision changes
• mental/mood changes (such as depression)
• unexplained bleeding/bruising
• unusual tiredness
• signs of kidney problems (such as change in the amount of urine)

Terbinafine may rarely cause serious (possibly fatal) liver disease. Get medical help right away if you have any symptoms of liver damage, such as:

• nausea/vomiting that doesn't stop
• loss of appetite
• severe stomach/abdominal pain
• yellowing eyes/skin
• dark urine

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• fever
• swollen lymph nodes
• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking terbinafine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• immune system problems
• kidney disease
• liver disease
• lupus

Limit alcoholic beverages. Daily use of alcohol may increase your chance for serious side effects.

This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Fungal nail infection treatment can usually wait until after you have had your baby. Discuss the risks and benefits with your doctor.

This drug passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Terbinafine can slow down the removal of other drugs from your body, which may affect how they work. Examples of affected drugs include pimozide, thioridazine, among others.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

This medication has been prescribed for your current condition only. Do not use it later for another infection unless your doctor tells you to.

Lab and/or medical tests (such as complete blood counts, liver function) should be done before you start taking this medication and while you are taking it. Keep all medical and lab appointments. Consult your doctor for more details.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.