Patient Information on Terbinafine for Fungal Toenail Infections

What is Terbinafine?

Terbinafine is an antifungal medication commonly used to treat fungal infections of the toenails and fingernails. It works by killing the fungi causing the infection, which helps the affected nail to heal.

How does Terbinafine work?

Terbinafine works by stopping the growth of the fungi. It targets a part of the fungal cell membrane, called ergosterol, which is essential for the fungus’s survival. By inhibiting the production of ergosterol, terbinafine prevents the fungus from growing and spreading.

How is Terbinafine taken?

Terbinafine is typically taken as an oral tablet. The usual course of treatment for a fungal toenail infection lasts for around 6 weeks, but this may vary depending on the severity of the infection and the recommendation of your healthcare provider.

What are the potential side effects of Terbinafine?

Like all medications, terbinafine can cause side effects. Most people tolerate it well, but some may experience side effects. These can include:

• Common side effects:
  • Gastrointestinal symptoms such as nausea, indigestion, or loss of appetite.
  • Headache.
  • Skin rash.
• Serious side effects (less common):
  • Liver issues: Terbinafine can affect liver function. This can lead to liver damage in some cases, which is why liver function should be monitored during treatment, especially if you are at higher risk (e.g., have a history of liver disease or drink alcohol regularly).
  • Allergic reactions: Symptoms may include swelling, difficulty breathing, or severe skin reactions.
  • Taste disturbances: Some people may experience a change in taste, which is usually reversible after discontinuing the medication.

Liver Function Monitoring

Terbinafine has been associated with liver toxicity, which can sometimes be severe. Because of this, your doctor will likely monitor your liver function while you are taking this medication. Regular blood tests may be required to check your liver enzymes. You should be aware of the signs of liver problems, such as:

• Unexplained fatigue.
• Yellowing of the skin or eyes (jaundice).
• Dark urine or pale stools.
• Abdominal pain, particularly in the upper right side.

If you experience any of these symptoms, contact your healthcare provider immediately.

Who should not take Terbinafine?

• People with liver disease: If you have any form of liver disease, terbinafine may not be suitable for you.
• Pregnancy and breastfeeding: Terbinafine is generally not recommended during pregnancy or breastfeeding unless advised by your doctor.
• Children: Terbinafine is not usually prescribed for children under 12 years old unless specifically recommended by a healthcare provider.

What should you do before starting Terbinafine?

Before starting treatment with terbinafine, inform your doctor about:

• Any history of liver disease or other liver problems.
• Any other medications you are taking (including over-the-counter medicines, vitamins, or herbal supplements).
• Any allergies you have, particularly to other antifungal medications.

What happens if I miss a dose of Terbinafine?

If you miss a dose of terbinafine, take it as soon as you remember, unless it is nearly time for your next dose. Do not take two doses at once to make up for a missed dose.

Key Considerations

• Take terbinafine exactly as prescribed by your healthcare provider.
• Attend all follow-up appointments to monitor for any side effects, particularly those related to liver function.
• Do not stop taking the medication without consulting your doctor, even if you start feeling better. Fungal infections can persist beneath the surface and may not show immediate improvement in the appearance of your nails.

Further Information

For more detailed information on terbinafine, including potential drug interactions and full prescribing details, you can refer to the British National Formulary (BNF) or Clinical Knowledge Summaries (CKS).

If you have any concerns or experience any unusual symptoms while on terbinafine, do not hesitate to contact your healthcare provider.