Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Cream, External, as hydrochloride:
LamISIL AT: 1% (12 g, 24 g [DSC], 30 g, 36 g [DSC], 42 g) [contains benzyl alcohol, cetyl alcohol]
LamISIL AT Jock Itch: 1% (12 g) [contains benzyl alcohol, cetyl alcohol]
Generic: 1% (15 g, 30 g)
Gel, External:
LamISIL Advanced: 1% (12 g [DSC]) [contains alcohol, usp]
Solution, External, as hydrochloride:
LamISIL AT Spray: 1% (125 mL [DSC]) [contains alcohol, usp, propylene glycol]
Pharmacology
Mechanism of Action
Synthetic allylamine derivative that inhibits squalene epoxidase, a key enzyme in sterol biosynthesis in fungi. This results in a deficiency in ergosterol within the fungal cell membrane and results in fungal cell death.
Pharmacokinetics/Pharmacodynamics
Absorption
Limited (<5%)
Distribution
Distributed to sebum and skin predominantly
Half-Life Elimination
14 to 35 hours
Use: Labeled Indications
Dermatologic fungal infections:
US products [OTC]: Treatment of tinea pedis (athlete's foot), tinea cruris (jock itch), and tinea corporis (ringworm)
Canadian products [prescription only]: Treatment of dermatologic fungal skin infections (including tinea pedis, tinea cruris, tinea corporis, cutaneous candidiasis, and tinea versicolor) in adults.
Contraindications
There are no contraindications listed within the manufacturer's labeling.
Canadian labeling: Hypersensitivity to terbinafine or any component of the formulation
Dosage and Administration
Dosing: Adult
OTC labeling:
Tinea pedis: Topical:
Cream: Apply between the toes to affected area twice daily for at least 1 week; apply on the bottom or sides of feet twice daily for 2 weeks
Gel: Apply to affected area once daily at bedtime for at least 1 week
Spray: Apply to affected area once daily for at least 1 week
Tinea corporis, Tinea cruris: Topical:
Cream: Apply to affected area once daily for 1 week
Gel: Apply to affected area once daily for 1 week
Spray: Apply to affected area once daily for 1 week
Canadian products [Rx only]:
Tinea pedis, Tinea corporis, Tinea cruris: Topical: Cream, Spray: Apply to affected area(s) once daily for at least 1 week
Cutaneous candidiasis: Topical: Cream: Apply to affected area once or twice daily for 1 to 2 weeks
Tinea versicolor: Topical:
Cream: Apply to affected area once or twice daily for 1 to 2 weeks
Spray: Apply to affected area twice daily for 1 week
Dosing: Geriatric
Refer to adult dosing.
Dosing: Pediatric
Pityriasis (tinea) versicolor: Limited data available: Children ≥12 years and Adolescents: Topical: Solution (spray): Apply to affected area once daily for 1 week (Bradley 2017; Red Book [AAP 2015])
Tinea corporis (ringworm): Children ≥12 years and Adolescents: Topical: Cream, gel: Apply to affected area once daily for at least 1 week
Tinea cruris (jock itch): Children ≥12 years and Adolescents: Topical: Cream, gel, solution (spray): Apply to affected area once daily for at least 1 week
Tinea pedis (athlete’s foot): Children ≥12 years and Adolescents: Topical:
Cream: Apply between the toes to affected area twice daily for at least 1 week; apply on the bottom or sides of feet twice daily for 2 weeks
Gel: Apply to affected area once daily at bedtime for at least 1 week
Administration
Topical: Wash affected area with soap and water prior to use and dry completely; wash hands after use.
Spray: Hold 4 to 6 inches from skin during application.
Storage
Cream: Store at 20°C to 25°C (68°F to 77°F).
Gel: Store at ≤30°C (≤86°F).
Solution: Store at 8°C to 25°C (46°F to 77°F).
Drug Interactions
There are no known significant interactions.
Adverse Reactions
1% to 10%:
Dermatologic: Burning sensation of skin, contact dermatitis, exfoliation of skin, pruritus, skin irritation, skin rash, stinging of the skin, xeroderma
Local: Local irritation
Warnings/Precautions
Concerns related to adverse events:
- Local irritation: If irritation/sensitivity develops, discontinue therapy and institute appropriate alternative therapy.
Dosage form specific issues:
- Benzyl alcohol and derivatives: Some dosage forms may contain benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol with caution in neonates. See manufacturer's labeling.
Other warnings/precautions:
- Appropriate use: For topical use only. Not intended for ophthalmologic, oral, or vaginal administration. Do not use on nails or scalp.
Pregnancy
Pregnancy Considerations
Systemic absorption is limited following topical application. If antifungal treatment cannot be delayed until after pregnancy, topical therapy when appropriate may be considered (Kaul 2017).
Patient Education
What is this drug used for?
- It is used to treat fungal infections of the skin.
Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:
- Severe skin irritation
- Signs of a significant reaction like 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. Talk to your doctor if you have questions.
Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.
