Terbinafine

Terbinafine (ter-bin’a-feen), sold most commonly under the brand name Lamosil® is an allyamine derivative that is used as both oral and topical broad spectrum antifungal agent.

Terbinafine is on the WHO’s list of essential medicine.

Action:
Terbinafine interferes with the cell membrane permeability in fungi such as Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, Microsporum canis, Microsporum audouinii, Microsporum gypseum and Candida species.

• inhibits squalene epoxidase  inhibits ergosterol synthesis
• contraindications – liver or renal disease
• major side effects: liver toxicity; severe neutropenia; agranulocytosis, pancytopenia, anaphylaxis, eye changes.
• maybe liver function tests if at risk for monitoring if used > 6 weeks
• interactions – lowers cyclosporine levels

Dosage:
250/mg/day for 12 weeks for toenails
Topical formulation

Contraindications:
Hypersensitivity to terbinafine or to any of the agents in the formulation.
Severe, chronic or active hepatic disease.

Interactions:
Cimetidine decrease the clearance of terbinafine, increasing its effect
Rifampin: increased terbinafine clearance

Pharmacokinetics:
Bioavailability Readily absorbed: 70–90%
Distribution: Extensive, most to hair,
scalp, nails; excreted in
breast milk; protein binding
99%
Protein binding >99%
Metabolism liver
Elimination half-life Highly variable

Adverse effects:
CNS: Depression
EENT: Tinnitus, hearing impairment
GI: Diarrhea, dyspepsia, abdominal pain,
nausea, hepatitis
HEMA: Neutropenia
INTEG: Rash, pruritus, urticaria, StevensJohnson syndrome, photosensitivity
MISC: Headache, hepatic enzyme changes,
taste, visual/olfactory disturbance

Brand names: Lamosil® (Novartis); Silka; and others
Chemical formula: C₂₁H₂₅N
Do not confuse with: terbutaline

Terbinafine Resistance:
Becoming a problem.
Fungi are mutating

Other anti-fungal drugs:

Antibiotics	Polyenes:	Nystatin	Amphotericin B	Hamycin
	Heterocyclic benzofuran:	Griseofulvin
	Echinocandins:	Caspofungin	Micafungin	Anidulafungin
Azoles:	Imidazoles:	Topical:	Clotrimazole	Econazole	Miconazole
			Bifonazole
		Systemic:	Ketoconazole
	Triazoles:	Fluconazole	Itraconazole	Voriconazole	Posaconazole
		Efinaconazole
Morpholines:	Amorolfine
Allylamines:	Terbinafine (oral)	Terbinafine (topical)
Other topical agents:	Tolnaftate	Benzoic acid	Butenafine	Sodium thiosulfate	Quiniodochlor
	Undecylenic acid	Ciclopirox olamine	Gentian Violet

In Australia, terbinafine is on the National Podiatry Scheduled Medicines List.

Related Topics:
Topical terbinafine

External Links:
Lamisil and alcohol (Podiatry Arena)

Page last updated: @ 2:29 am