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, usually once a day or as directed by your doctor. 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. Stopping the medication too early may allow the fungus to continue to grow, which may result in a return of the infection. Tell your doctor if your condition persists or worsens.
Diarrhea or stomach upset may occur. If either of these effects lasts or gets worse, tell your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she 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.
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.
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. Some products that may interact with this drug include: warfarin, drugs affecting liver enzymes that remove terbinafine from your body (such as amiodarone, cimetidine, rifampin, azole antifungals such as fluconazole/ketoconazole), drugs removed from your body by certain liver enzymes (such as tricyclic antidepressants, SSRI antidepressants, beta blockers, dextromethorphan, thioridazine, drugs to treat heart rhythm problems, monoamine oxidase inhibitors type B such as rasagiline).
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 their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.