(TER bin a feen)
- Terbinafine HCl
- Terbinafine Hydrochloride
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Terbinex: 250 mg & 1%
LamISIL: 125 mg (1 ea [DSC], 14 ea [DSC]); 187.5 mg (1 ea [DSC], 14 ea [DSC]) [contains polyethylene glycol]
LamISIL: 250 mg
Generic: 250 mg
Brand Names: U.S.
- Antifungal Agent, Oral
Synthetic allylamine derivative which inhibits squalene epoxidase, a key enzyme in sterol biosynthesis in fungi. This results in a deficiency in ergosterol within the fungal cell wall and results in fungal cell death.
Children and Adults: >70%
Distributed to sebum and skin predominantly
Hepatic predominantly via CYP1A2, 3A4, 2C8, 2C9, and 2C19 to inactive metabolites
Urine (80%, primarily as inactive metabolites); feces (20%) (Debruyne 2001)
Clearance: Children (14 to 68 kg): 15.6 to 26.7 L/hour
Time to Peak
Plasma: Children and Adults: Within 2 hours
Terminal half-life: 200 to 400 hours; very slow release of drug from skin and adipose tissues occurs; effective half-life: Children: 27 to 31 hours; Adults: ~36 hours
Special Populations: Renal Function Impairment
In CrCl ≤50 mL/minute, terbinafine clearance is decreased 50%.
Special Populations: Hepatic Function Impairment
In hepatic cirrhosis, terbinafine clearance is decreased 50%.
Use: Labeled Indications
Onychomycosis (tablets only): Treatment of onychomycosis of the toenail or fingernail caused by dermatophytes (tinea unguium).
Tinea capitis (granules only): Treatment of tinea capitis in patients 4 years and older.
Sporotrichosis: Treatment of sporotrichosis (lymphocutaneous and cutaneous)
Hypersensitivity to terbinafine or any component of the formulation
Canadian labeling: Additional contraindications (not in US labeling): Chronic or active hepatic disease
Onychomycosis: Oral: Tablet: Fingernail: 250 mg once daily for 6 weeks; Toenail: 250 mg once daily for 12 weeks
Missed doses: If a dose is missed, take as soon as remembered, unless it is less than 4 hours before the next dose is due.
Tinea capitis (patients >35 kg): Oral: Granules: 250 mg once daily for 6 weeks
Tinea corporis, tinea cruris (off-label use): Oral: 250 mg daily in 1 to 2 divided doses for 2 to 6 weeks (Del Palacio Hernanz 1990; Gupta 2008)
Tinea pedis/manuum (off-label use): Oral: 250 mg once daily for 2 weeks (Gupta 2008; Tausch 1998)
Sporotrichosis, lymphocutaneous and cutaneous (off-label use): Oral: 500 mg twice daily as alternative therapy; treat for 2 to 4 weeks after resolution of all lesions (usual duration: 3 to 6 months) (Kauffman 2007)
Use with caution; refer to adult dosing.
Tinea capitis: Oral: Granules: Children ≥4 years and Adolescents:
<25 kg: 125 mg once daily for 6 weeks
25 to 35 kg: 187.5 mg once daily for 6 weeks
>35 kg: 250 mg once daily for 6 weeks
Onychomycosis (off-label use) (Gupta 1997): Oral: Tablet: Children and Adolescents:
10 to 20 kg: 62.5 mg once daily for 6 weeks (fingernails) or 12 weeks (toenails)
20 to 40 kg: 125 mg once daily for 6 weeks (fingernails) or 12 weeks (toenails)
>40 kg: 250 mg once daily for 6 weeks (fingernails) or 12 weeks (toenails)
Dosing: Renal Impairment
There are no dosage adjustments provided in the manufacturer’s labeling (has not been studied); however, clearance is decreased 50% in patients with CrCl ≤50 mL/minute.
Dosing: Hepatic Impairment
Use is not recommended in chronic or active hepatic disease.
A 25 mg/mL oral suspension may be made using tablets. Crush twenty 250 mg tablets and reduce to a fine powder. Add small amount of a 1:1 mixture of Ora-Sweet® and Ora-Plus® and mix to a uniform paste; mix while adding the vehicle in geometric proportions to almost 200 mL; transfer to a calibrated bottle, rinse mortar with vehicle, and add quantity of vehicle sufficient to make 200 mL. Label "shake well" and "refrigerate". Stable 42 days.Nahata MC, Pai VB, and Hipple TF, Pediatric Drug Formulations, 5th ed, Cincinnati, OH: Harvey Whitney Books Co, 2004.
Administer tablets without regard to meals. Administer granules with food; sprinkle granules on a spoonful of pudding or other soft, nonacidic food (eg, mashed potatoes); swallow entire spoonful without chewing; do not mix granules with applesauce or other fruit-based foods.
Granules: Store at 25°C (77°F); excursions permitted between 15°C to 30°C (59°F to 86°F).
Tablet: Store below 25°C (77°F). Protect from light.
Ajmaline: CYP2D6 Inhibitors (Moderate) may increase the serum concentration of Ajmaline. Monitor therapy
Amitriptyline: Terbinafine (Systemic) may increase the serum concentration of Amitriptyline. Management: Monitor for increased effects/toxicity of amitriptyline during concomitant administration with terbinafine. Reduced dosages of amitriptyline may be needed. Consider therapy modification
ARIPiprazole: CYP2D6 Inhibitors (Moderate) may increase the serum concentration of ARIPiprazole. Management: Monitor for increased aripiprazole pharmacologic effects. Aripiprazole dose adjustments may or may not be required based on concomitant therapy and/or indication. Consult full interaction monograph for specific recommendations. Monitor therapy
Brexpiprazole: CYP2D6 Inhibitors (Moderate) may increase the serum concentration of Brexpiprazole. Management: If brexpiprazole is to be used together with both a moderate CYP2D6 inhibitor and a strong or moderate CYP3A4 inhibitor, the brexpiprazole dose should be reduced to 25% of the usual dose. Monitor therapy
Codeine: CYP2D6 Inhibitors (Moderate) may diminish the therapeutic effect of Codeine. These CYP2D6 inhibitors may prevent the metabolic conversion of codeine to its active metabolite morphine. Monitor therapy
CYP2D6 Substrates: CYP2D6 Inhibitors (Moderate) may decrease the metabolism of CYP2D6 Substrates. Exceptions: Tamoxifen. Monitor therapy
Desipramine: Terbinafine (Systemic) may increase the serum concentration of Desipramine. Management: Monitor for increased effects/toxicity of desipramine during concomitant administration with terbinafine. Reduced dosages of desipramine may be needed. Consider therapy modification
DOXOrubicin (Conventional): CYP2D6 Inhibitors (Moderate) may increase the serum concentration of DOXOrubicin (Conventional). Management: Seek alternatives to moderate CYP2D6 inhibitors in patients treated with doxorubicin whenever possible. One U.S. manufacturer (Pfizer Inc.) recommends that these combinations be avoided. Consider therapy modification
Eliglustat: CYP2D6 Inhibitors (Moderate) may increase the serum concentration of Eliglustat. Management: Reduce the eliglustat dose to 84 mg daily. Avoid use of eliglustat in combination with a moderate CYP2D6 inhibitor and a strong or moderate CYP3A4 inhibitor. Consider therapy modification
Fesoterodine: CYP2D6 Inhibitors may increase serum concentrations of the active metabolite(s) of Fesoterodine. Monitor therapy
Imipramine: Terbinafine (Systemic) may increase the serum concentration of Imipramine. Management: Monitor for increased effects/toxicity of imipramine during concomitant administration with terbinafine. Reduced dosages of imipramine may be needed. Consider therapy modification
Metoprolol: CYP2D6 Inhibitors may increase the serum concentration of Metoprolol. Management: Consider an alternative for one of the interacting drugs in order to avoid metoprolol toxicity. If the combination must be used, monitor response to metoprolol closely. Metoprolol dose reductions may be necessary. Consider therapy modification
Nebivolol: CYP2D6 Inhibitors (Moderate) may increase the serum concentration of Nebivolol. Monitor therapy
Nortriptyline: Terbinafine (Systemic) may increase the serum concentration of Nortriptyline. Management: Monitor for increased effects/toxicity of nortriptyline during concomitant administration with terbinafine. Reduced dosages of nortriptyline may be needed. Consider therapy modification
Perhexiline: CYP2D6 Inhibitors may increase the serum concentration of Perhexiline. Management: Consider alternatives to this combination if possible. If combined, monitor for increased perhexiline serum concentrations and toxicities (eg, hypoglycemia, neuropathy, liver dysfunction). Perhexiline dose reductions will likely be required. Consider therapy modification
Propafenone: May increase the serum concentration of CYP2D6 Inhibitors (Moderate). Monitor therapy
RifAMPin: May decrease the serum concentration of Terbinafine (Systemic). Monitor therapy
Saccharomyces boulardii: Antifungal Agents (Systemic, Oral) may diminish the therapeutic effect of Saccharomyces boulardii. Avoid combination
Tamoxifen: CYP2D6 Inhibitors (Moderate) may decrease serum concentrations of the active metabolite(s) of Tamoxifen. Specifically, CYP2D6 inhibitors may decrease the metabolic formation of highly potent active metabolites. Management: Consider alternatives with less of an inhibitory effect on CYP2D6 activity when possible. Consider therapy modification
Thioridazine: CYP2D6 Inhibitors may increase the serum concentration of Thioridazine. Avoid combination
TraMADol: CYP2D6 Inhibitors (Moderate) may diminish the therapeutic effect of TraMADol. These CYP2D6 inhibitors may prevent the metabolic conversion of tramadol to its active metabolite that accounts for much of its opioid-like effects. Monitor therapy
Adverse events listed for tablets unless otherwise specified. Granules were studied in patients 4-12 years of age.
>10%: Central nervous system: Headache (13%; granules 7%)
1% to 10%:
Dermatologic: Skin rash (6%; granules 2%), pruritus (3%; granules 1%), urticaria (1%)
Gastrointestinal: Diarrhea (6%; granules 3%), vomiting (<1%; granules 5%), dyspepsia (4%), dysgeusia (may be severe and result in weight loss and depression; 3%), nausea (3%; granules 2%), abdominal pain (2%; granules 2% to 4%), flatulence (2%), sore throat (granules 2%), toothache (granules 1%)
Hepatic: Liver enzyme disorder (3%)
Infection: Influenza (granules 2%)
Ophthalmic: Visual disturbance (1%)
Respiratory: Nasopharyngitis (granules 10%), cough (granules 6%), upper respiratory tract infection (granules 5%), nasal congestion (granules 2%), rhinorrhea (granules 2%)
Miscellaneous: Fever (granules 7%)
<1% (Limited to important or life-threatening): Acute generalized exanthematous pustulosis, acute pancreatitis, agranulocytosis, alopecia, altered sense of smell, anaphylaxis, angioedema, depression, DRESS syndrome, exacerbation of psoriasis, exacerbation of systemic lupus erythematosus, hepatic disease, hepatic failure, hypersensitivity reaction, pancytopenia, rhabdomyolysis, severe neutropenia, Stevens-Johnson syndrome, thrombocytopenia, toxic epidermal necrolysis, vasculitis, visual field loss
Concerns related to adverse effects:
• Allylamine antifungal hypersensitivity: Use caution in patients sensitive to allylamine antifungals (eg, naftifine, butenafine); cross-sensitivity to terbinafine may exist.
• Depression: Has been reported with use; instruct patients to report depressive symptoms/mood changes.
• Gastrointestinal effects: Taste disturbance (including loss of taste) may occur and severe cases resulting in weight loss or depression have been reported; resolution may be delayed (eg, several weeks to >1 year) following discontinuation of therapy or in some cases, disturbance may be permanent. Discontinue therapy in patients with symptoms of taste disturbance.
• Hematologic effects: Transient decreases in absolute lymphocyte counts were observed in clinical trials; severe neutropenia (reversible upon discontinuation) has also been reported. Monitor CBC in patients with pre-existing immunosuppression if therapy is to continue >6 weeks. Discontinue therapy if ANC ≤1000/mm3.
• Hepatic failure: Cases of hepatic failure, some leading to liver transplant or death, have been reported. If clinical evidence of liver injury develops (eg, nausea, anorexia, fatigue, vomiting, right upper abdominal pain, jaundice, dark urine, pale stools), assess hepatic function immediately; discontinue therapy in cases of elevated liver function tests.
• Hypersensitivity: Serious skin and hypersensitivity reactions (eg, Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme, exfoliative dermatitis, bullous dermatitis, drug reaction with eosinophilia and systemic symptoms [DRESS] syndrome) have occurred. If progressive skin rash or signs and symptoms of a hypersensitivity reaction occur, discontinue treatment.
• Ocular effects: Although rare, changes in the ocular lens and retina have been reported; discontinuation of therapy may be required.
• Respiratory effects: Smell disturbance (including loss of smell) has been reported; resolution may be delayed (eg, >1 year) following discontinuation of therapy or in some cases, disturbance may be permanent. Discontinue therapy in patients with symptoms of smell disturbance.
• Autoimmune disease (Lupus): Precipitation or exacerbation of cutaneous or systemic lupus erythematosus has been observed; discontinue if signs and/or symptoms develop.
• Hepatic impairment: Use is not recommended in patients with active or chronic liver disease; clearance is reduced by ~50% in hepatic cirrhosis.
• Renal impairment: Use with caution in patients with renal dysfunction (CrCl ≤50 mL/minute); clearance is reduced by ~50%.
• Appropriate use: Due to potential toxicity, confirmation of diagnostic testing of nail or skin specimens prior to treatment of onychomycosis or dermatomycosis is recommended.
AST/ALT prior to initiation, repeat if used >6 weeks; CBC (if used >6 weeks; immunosuppressed patients only); taste and/or smell disturbances
Pregnancy Risk Factor
Adverse events were not observed in animal reproduction studies. Avoid use in pregnancy since treatment of onychomycosis is postponable.
• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Patient may experience headache, abdominal pain, diarrhea, bloating, flatulence, vomiting, or nausea. Have patient report immediately to prescriber signs of infection, signs of liver problems (dark urine, feeling tired, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin or eyes), dysphagia, enlarged lymph nodes, seizures, skin discoloration, pale skin, severe muscle pain, severe joint pain, bruising, bleeding, severe loss of strength and energy, vision changes, hearing impairment, change in taste, loss of taste, weight loss, depression, lack of appetite, or signs of Stevens-Johnson syndrome/toxic epidermal necrolysis (red, swollen, blistered, or peeling skin [with or without fever]; red or irritated eyes; or sores in mouth, throat, nose, or eyes) (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.