Antifungal Therapy Management

Baseline Testing and Monitoring Recommendations

Baseline liver function tests (LFTs) should be performed for all patients before prescribing terbinafine, and complete blood count should also be obtained in patients with a history of hepatotoxicity, pre-existing liver disease, heavy alcohol consumption, or hematological abnormalities, as recommended by the British Association of Dermatologists 1
For high-risk patients, such as those with pre-existing liver disease, concomitant hepatotoxic medications, or abnormal baseline LFTs, monitoring of LFTs periodically during treatment is recommended, although no specific schedule is provided, with the British Association of Dermatologists suggesting consideration of individual patient risk factors 1
Liver function tests should be monitored at regular intervals, such as weeks 1, 2, and 4 after starting therapy, then every 3 months, and immediately discontinuing terbinafine if there is biochemical or clinical evidence of liver injury, as recommended by the FDA and the Clinical Infectious Diseases guideline 2, 3

Patients should be instructed to report immediately any symptoms of liver injury, including persistent nausea, anorexia, fatigue, vomiting, right upper abdominal pain, jaundice, dark urine, and pale stools, with clinical monitoring for symptoms being more effective than laboratory screening for detecting liver injury in patients taking terbinafine 1
Patients should be advised to report immediately any symptoms of liver injury and counseled on avoiding alcohol during treatment, as recommended by the National Institutes of Health and the Clinical Infectious Diseases guideline 2, 3

Terbinafine is not recommended for patients with active or chronic liver disease, and alternative antifungal agents should be considered for patients with pre-existing liver disease or on concomitant hepatotoxic medications, as recommended by the British Association of Dermatologists 1
Active or chronic liver disease is a contraindication for terbinafine treatment, and oral antifungal therapy should not be initiated until liver enzymes normalize, as both terbinafine and itraconazole carry a significant risk of hepatotoxicity in patients with pre-existing liver dysfunction 1, 3
Patients at high risk for rhabdomyolysis should avoid terbinafine and select alternative antifungals, and patients on terbinafine should be monitored for liver function and muscle symptoms, as recommended by the American Academy of Dermatology and the American Academy of Pediatrics 4, 2

Itraconazole and fluconazole are recommended as alternative antifungals for patients at risk for rhabdomyolysis or with specific fungal infections, with dosages ranging from 100 mg daily for 4 weeks to 200 mg twice daily for 1 week, effective against Trichophyton and Microsporum species, as recommended by the American Academy of Dermatology and the American Academy of Pediatrics 4, 5
Itraconazole is recommended as first-line treatment for Candida onychomycosis, with a dosage of 200 mg daily or 400 mg pulse therapy, according to the British Journal of Dermatology 1
Ciclopirox olamine 0.77% cream/gel, clotrimazole 1% cream, and butenafine can be applied twice daily for 2-4 weeks for limited disease, as recommended by the American Academy of Dermatology 5
Topical antifungal solutions, such as Ciclopirox nail lacquer, Amorolfine, Efinaconazole, and Tavaborole, have lower efficacy than oral agents but avoid systemic toxicity, as stated by the British Journal of Dermatology 1

Terbinafine is recommended as first-line treatment for dermatophyte onychomycosis, with a dosage of 250 mg daily for 6 weeks for fingernails and 12 weeks for toenails, according to the British Journal of Dermatology 1
Treatment duration should be 2-4 weeks for terbinafine, and 6-8 weeks for griseofulvin, as recommended by the American Academy of Dermatology 4
For tinea pedis/cruris, oral itraconazole can be used, with a dosage of 100 mg daily for 2 weeks or 200 mg daily for 1 week, as recommended by the American Academy of Dermatology 5

Terbinafine can be safely administered to patients taking lisinopril or hydrochlorothiazide without concerns about clinically significant drug interactions, and no dosage adjustments are necessary when used in combination, according to the American College of Cardiology 6
Terbinafine has minimal drug-drug interactions with other medications, such as fluticasone, making it a safe combination with no significant clinical concerns regarding mortality, morbidity, or quality of life, as supported by the British Journal of Dermatology 1
Patients should be monitored for signs of serious adverse effects, including Stevens-Johnson syndrome, toxic epidermal necrolysis, and hepatotoxicity, and informed about common side effects of terbinafine, including gastrointestinal issues and dermatological reactions, as recommended by the British Association of Dermatologists 1