Is it safe for a 30-year-old female with elevated liver enzymes (alanine transaminase (ALT) and aspartate transaminase (AST)) to take terbinafine (Lamisil) for toenail fungus?

From the Guidelines

Terbinafine is not recommended for a 30-year-old female with elevated liver enzymes (ALT 80 and AST 47) due to its potential to cause further liver damage. According to the British Association of Dermatologists' guidelines for the management of onychomycosis 2014 1, terbinafine is contraindicated in patients with hepatic impairment. The guidelines suggest that baseline liver function tests and a complete full blood count are recommended in adult patients with a history of hepatotoxicity or haematological abnormalities.

Key Considerations

• Terbinafine is metabolized in the liver and has been associated with rare but serious hepatotoxicity 1.
• The patient's elevated liver enzymes (ALT 80 and AST 47) indicate a potential liver function abnormality, which may be exacerbated by terbinafine treatment.
• Alternative treatments for toenail fungus, such as topical antifungals like ciclopirox (Penlac) nail lacquer or efinaconazole (Jublia), may be more appropriate due to their minimal systemic absorption and less impact on the liver.

Recommendations

• The patient should undergo a complete liver function assessment to determine the cause and severity of the enzyme elevation.
• If toenail fungus is severe and systemic treatment is necessary, the patient should discuss with her doctor about monitoring liver function before and during treatment, or exploring other oral antifungals with potentially better safety profiles for her specific situation.
• The underlying cause of elevated liver enzymes should be addressed before considering any hepatically metabolized medications.

From the FDA Drug Label

1. 1 Hepatotoxicity Cases of liver failure, some leading to liver transplant or death, have occurred with the use of terbinafine tablets in individuals with and without pre-existing liver disease. ... Terbinafine tablets are not recommended for patients with chronic or active liver disease Before prescribing terbinafine tablets, liver function tests should be performed since hepatotoxicity may occur in patients with and without pre-existing liver disease.

Patients prescribed terbinafine tablets should be warned to report immediately to their physician any symptoms of persistent nausea, anorexia, fatigue, vomiting, right upper abdominal pain or jaundice, dark urine, or pale stools.

The patient has elevated liver enzymes (ALT 80 and AST 47), which indicates potential liver injury. Terbinafine is not recommended for patients with elevated liver enzymes, as it may worsen liver function.

• The patient's liver function tests indicate a potential risk for hepatotoxicity.
• Terbinafine should not be prescribed to this patient due to the risk of exacerbating liver injury 2.

From the Research

Safety of Terbinafine for Toenail Fungus with Elevated Liver Enzymes

The use of terbinafine for toenail fungus in individuals with elevated liver enzymes, such as ALT (alanine transaminase) and AST (aspartate transaminase), requires careful consideration. Key points to consider include:

• Terbinafine's efficacy in treating dermatophyte onychomycosis, as demonstrated in studies like the L.I.ON. study 3, which showed superior mycologic and complete cure rates compared to itraconazole.
• The potential for terbinafine to cause liver enzyme elevations and, in rare cases, severe acute liver injury, as reported in case studies and reviews 4, 5, 6.
• The importance of monitoring liver function before and during treatment with terbinafine, especially in patients with pre-existing liver enzyme elevations.

Considerations for the 30-Year-Old Female

Given the patient's elevated liver enzymes (ALT 80 and AST 47), it is crucial to weigh the benefits of terbinafine treatment against the potential risks. Considerations include:

• The patient's age and overall health status, which may influence the risk of liver injury.
• The severity of the toenail fungus infection and the potential impact on quality of life.
• Alternative treatment options, such as topical antifungals or other oral medications, which may have a more favorable safety profile.

Monitoring and Precautions

If terbinafine is prescribed, regular monitoring of liver function is essential to minimize the risk of liver injury. This includes:

• Baseline liver function tests before starting treatment.
• Periodic monitoring of liver enzymes (e.g., every 4-6 weeks) during treatment.
• Prompt evaluation of any symptoms suggestive of liver injury, such as jaundice, dark urine, or abdominal pain.

It is essential to consult with a healthcare professional to determine the best course of treatment for the patient's specific situation, taking into account the potential benefits and risks of terbinafine therapy 3, 6.