TERBINAFINE
Background and Date of Approval
Terbinafine is an antifungal medication approved by the Food and Drug Administration (FDA) on March 9, 1999, as a topical cream formulation. An oral form received FDA approval on September 28, 2007. It is indicated for the treatment of fungal infections affecting the skin and nails, including athlete's foot, ringworm, and toenail fungus.
Uses
Terbinafine is an antifungal medication primarily used to treat dermatophyte infections, such as tinea corporis, tinea cruris, tinea pedis, and onychomycosis. It is effective in treating superficial fungal infections of the skin, nails, and hair by targeting the underlying fungal cause. Additionally, terbinafine is utilised for the treatment of onychomycosis, a fungal nail infection that is notoriously difficult to treat. It also serves as an alternative treatment for dermatophyte-induced infections in immunocompromised patients, offering relief when other therapies fail.
How is it administered?
Take terbinafine with or without food. If taking the oral form, swallow the tablet whole with a glass of water. Avoid crushing, chewing, or breaking the tablet. Adhere to the prescribed dosage and duration of treatment. For onychomycosis, therapy may last several months due to slow nail regrowth.
Side Effects
Side effects are unwanted symptoms caused by medicines. Although all drugs can cause side effects, not everyone experiences them. Common side effects of Terbinafine: Gastrointestinal discomfort (nausea, dyspepsia) Headache Skin rash Diarrhea Altered taste sensation (dysgeusia) Serious side effects of Terbinafine: Hepatotoxicity (liver damage) Severe allergic reactions (urticaria, angioedema) Acute generalised exanthematous pustulosis Neutropenia (low white blood cell count) Persistent or unexplained gastrointestinal symptoms Yellowing of the skin or eyes (jaundice) Renal dysfunction (rare)
Warnings
Serious Reactions: Terbinafine may cause severe liver damage, which can be life-threatening. It should be discontinued immediately if signs of liver problems, such as jaundice, dark urine, or persistent abdominal pain, occur. Monitoring: Regular liver function tests are recommended before starting therapy and during treatment, particularly for those with pre-existing liver conditions. Hepatic Risk: Terbinafine is contraindicated in patients with chronic or active liver disease. In such cases, close monitoring or an alternative therapy should be considered. Allergic Reactions: Discontinue use if serious allergic reactions, such as rash, itching, or difficulty breathing, occur.
Precautions
Patients with impaired liver function should use terbinafine cautiously, as it can worsen liver damage. Those with renal impairment should also exercise caution and regularly monitor kidney function during treatment. Although terbinafine is classified as a Category B medication for pregnancy and is generally considered safe, it should still be used with caution. Pregnant women or those planning to become pregnant should consult a doctor before using it. Elderly patients may require dosage adjustments, especially if they have underlying renal or hepatic dysfunction.
Word of Advice
Monitor for signs of liver dysfunction including jaundice, dark urine, or abdominal pain whilst taking terbinafine. Contact your doctor immediately if severe side effects develop. Continue your prescribed treatment regimen and do not stop or change the dosage without consulting your doctor. Regular blood tests, including liver function tests, may be required during treatment. Inform your doctor promptly if you experience signs of allergic reaction or any unusual symptoms.
References
1. Babu PR, Pravin AJS, Deshmukh G, Dhoot D, Samant A, Kotak B. Efficacy and Safety of Terbinafine 500 mg Once Daily in Patients with Dermatophytosis. https://pmc.ncbi.nlm.nih.gov/articles/PMC5527721/ 2. Newland JG, Abdel-Rahman SM. Update on terbinafine with a focus on dermatophytoses. https://pmc.ncbi.nlm.nih.gov/articles/PMC3047923/ 3. van der Schroeff JG, Cirkel PK, Crijns MB, Van Dijk TJ, Govaert FJ, Groeneweg DA, Tazelaar DJ, De Wit RF, Wuite J. A randomized treatment duration-finding study of terbinafine in onychomycosis. https://pubmed.ncbi.nlm.nih.gov/1531927/
Frequently Asked Questions
What is terbinafine used to treat?
Terbinafine is used to treat fungal infections such as athlete's foot, ringworm, and fungal nail infections. It works by stopping the growth of the fungus.
Is terbinafine a steroid?
No, terbinafine is not a steroid. It is an antifungal medication used to treat fungal infections.
What is the best time to take terbinafine?
It is best to take terbinafine at the same time each day, with or without food. Follow your doctor's instructions for the specific dosage and timing.
Are terbinafine tablets safe?
Terbinafine tablets are generally safe when used as prescribed. However, they can cause side effects in some people, and regular monitoring by a doctor is recommended to check for liver issues or other concerns.
Who cannot use terbinafine?
People with liver disease or allergic reactions to terbinafine should not use it. Pregnant or breastfeeding women should also avoid it unless advised by a doctor. Additionally, those with a history of certain medical conditions, such as kidney problems, should consult a doctor before use.