|1. TYPE OF DRUG – TERBINAFINE|
|Terbinafine is an antifungal medication that fights infections caused by fungus.
|2. INDICATIONS (USE) – TERBINAFINE|
|For the treatment of dermatophyte infections of the toenail or fingernail caused by susceptible fungi. Also for the treatment of tinea capitis (scalp ringworm) and tinea corporis (body ringworm) or tinea cruris (jock itch).
|3. MECHANISM OF ACTION (MOA) – TERBINAFINE|
|Terbinafine is hypothesized to act by inhibiting squalene monooxygenase, thus blocking the biosynthesis of ergosterol, an essential component of fungal cell membranes. This inhibition also results in an accumulation of squalene, which is a substrate catalyzed to 2,3-oxydo squalene by squalene monooxygenase. The resultant high concentration of squalene and decreased amount of ergosterol are both thought to contribute to terbinafine’s antifungal activity.
|4. ROUTES OF ADMINISTRATION- TERBINAFINE|
|5. ONSET OF EFFECT OR ACTION- TERBINAFINE|
|Readily absorbed from gastrointestinal tract.
Protein binding > 99%
|6. DOSAGE (DOSING INFORMATION) – TERBINAFINE|
250 mg (1 tablet) PO daily for 6 weeks (fingernail) or 12 weeks (toenail)
Tinea Pedis (Off-label)
250 mg/day PO in single dose or divided q12hr for 2-6 weeks
Tinea Corporis, Tinea Cruris
250 mg/day PO in single dose or divided q12hr for 2-4 weeks
|7. HALF LIFE (DURATION OF ACTION) – TERBINAFINE|
|8. ADVERSE EFFECTS OR SIDE EFFECTS – TERBINAFINE|
|9. CONTRAINDICATIONS – TERBINAFINE|
|Terbinafine tablets are contraindicated in individuals with a history of allergic reaction to oral Terbinafine because of the risk of anaphylaxis.
|10. DRUG INTERACTIONS – TERBINAFINE|
|Terbinafine is an inhibitor of the CYP450 2D6 isozyme. Drugs predominantly metabolized by the CYP450 2D6 isozyme include the following drug classes: tricyclic antidepressants, selective serotonin reuptake inhibitors, beta-blockers, antiarrhythmics class 1C (e.g., flecainide and propafenone) and monoamine oxidase inhibitors Type B. Coadministration of Terbinafine tablets should be done with careful monitoring and may require a reduction in dose of the 2D6-metabolized drug.
|11. EXCRETION- TERBINAFINE|
|Terbinafine and its metabolites are excreted predominantly in the urine.