Are there contraindications to using long-term terbinafine (antifungal medication) for onychomycosis (fungal infection of the nail) in patients with a history of pulmonary embolism (blockage of an artery in the lungs) and hypercoagulation syndrome (thrombophilia)?

From the Guidelines

Terbinafine should be used with caution in patients with a history of pulmonary embolism and hypercoagulation syndrome, but it is not absolutely contraindicated. The primary contraindications for oral terbinafine include active or chronic liver disease, severe renal impairment, and hypersensitivity to the medication, as stated in the British Association of Dermatologists' guidelines for the management of onychomycosis 2014 1. For patients with hypercoagulable states, there is no established direct interaction between terbinafine and clotting factors or anticoagulant medications. However, any systemic medication should be approached carefully in patients with complex medical histories.

Before starting the standard treatment (typically 250mg daily for 6-12 weeks for fingernails or 12-16 weeks for toenails), these patients should have baseline liver function tests performed, as recommended by the guidelines 1. During treatment, they should be monitored for any unusual symptoms such as unexplained bleeding, bruising, or signs of thrombosis. Patients should continue their prescribed anticoagulation therapy without interruption while on terbinafine.

The benefit of treating onychomycosis should be weighed against potential risks, and topical treatments might be considered as an alternative first-line approach for patients with significant comorbidities, though they are generally less effective than oral therapy. According to the guidelines, terbinafine is generally preferred over itraconazole for the treatment of dermatophyte onychomycosis due to its higher efficacy and tolerability 1.

Key considerations for the use of terbinafine in patients with a history of pulmonary embolism and hypercoagulation syndrome include:

• Monitoring for signs of thrombosis or bleeding
• Continuing anticoagulation therapy as prescribed
• Weighing the benefits of treating onychomycosis against potential risks
• Considering alternative treatments, such as topical therapy, for patients with significant comorbidities. It is essential to follow the guidelines and take necessary precautions to minimize potential risks and ensure the best possible outcome for patients with onychomycosis and a history of pulmonary embolism and hypercoagulation syndrome, as supported by the guidelines 1.

From the Research

Contraindications for Long-Term Terbinafine Use

There are no direct research papers that discuss the contraindications of long-term terbinafine use in patients with a history of pulmonary embolism and hypercoagulation syndrome.

Safety of Oral Antifungals

• The safety of oral antifungals, including terbinafine, has been evaluated in several studies 2, 3, 4.
• These studies have identified potential adverse events associated with oral antifungals, including hepatic, renal, cutaneous, cardiovascular, neurological, hemopoietic, and obstetric events 2.
• However, none of these studies specifically address the use of terbinafine in patients with a history of pulmonary embolism and hypercoagulation syndrome.

Treatment of Onychomycosis

• Terbinafine is a commonly used oral antifungal agent for the treatment of onychomycosis 3, 5, 4.
• The efficacy and safety of terbinafine have been demonstrated in several studies, including those comparing it to other oral antifungal agents 3, 5, 4.
• However, the use of terbinafine in patients with a history of pulmonary embolism and hypercoagulation syndrome is not specifically addressed in these studies.

Long-Term Therapy for Pulmonary Embolism

• The long-term therapy for pulmonary embolism typically involves the use of oral anticoagulants for at least 3 months 6.
• The duration of oral anticoagulant treatment is determined by the balance between the benefit of treatment and the risk of bleeding and inconvenience 6.
• However, the use of terbinafine in patients with a history of pulmonary embolism and hypercoagulation syndrome is not discussed in this context.