TERFIL [Terbinafine] 125 mg Tablets
instructions
for the medical use of a medicinal product
TERFIL
Tradename
Terfil, Терфил
International non-proprietary
name or generic name
Terbinafine,
Тербинафин
Tablets
Composition
Each film-coated tablet contains:
active substance: terbinafine hydrochloride BP
equivalent to terbinafine 125 mg;
excipients: lactose monohydrate, starch, primogel, PVP K-30,
magnesium stearate, talc.
Antifungal agent.
Code
АТХ: D01VA02
Pharmacological properties
Pharmacodynamics
Terbinafine
is chemically an allylamine and has a broad spectrum of antifungal action. The
mechanism of action is associated with specific inhibition of the early stage
of sterol biosynthesis in the cell membrane of fungi. This leads to a
deficiency of ergosterol and to intracellular accumulation of squalene, which
causes the death of fungal cells. Terbinafine acts by inhibiting squalene
epoxidase in the cell membranes of fungi. This enzyme does not belong to the
cytochrome P450 system, so terbinafine does not affect the metabolism of
hormones or other drugs. Terbinafine has an effect on dermatophytes, yeast-like
and mold fungi, some dimorphic fungi. In low concentrations it has fungicidal
activity against dermatophytes (Trychophyton
rubrum, Trychophyton mentagrophytes, Trychophyton verrucosum, Trychophyton
violaceum, Trychophyton tonsurans, Microsporum canis, Epidermophyton floccosum),
mold fungi (including Aspergillus,
Cladosporium, Scopulariopsis brevicaulis). The effect on yeast fungi of the
genus Candida (mainly Candida albicans) can be fungicidal or
fungistatic depending on the type of fungus.
After
oral administration, terbinafine is well absorbed (>70%); the absolute
bioavailability of terbinafine due to the first-pass effect is approximately
50%. After a single oral dose of 250 mg, Cmax in plasma is reached after 1.5
hours and is 1.3 μg/ml. Food intake does not affect the
bioavailability of terbinafine.
Plasma
protein binding is 99%. During the first few weeks after the start of oral
administration, terbinafine accumulates in the skin and nail plates in
concentrations that provide fungicidal action.
As
a result of biotransformation, terbinafine is converted into metabolites that do
not have antifungal activity and are excreted mainly in the urine.
The
half-life (T½) is from 11 to 17 hours.
-
onychomycosis (fungal infection of the nails) caused by dermatophyte fungi; -
fungal infections of the skin - dermatomycosis of the trunk, shins, feet, as
well as yeast infections of the skin caused by fungi of the genus Candida (for example, Candida albicans) in cases where the
localization, severity or prevalence of the infection determine the
appropriateness of oral therapy.
Contraindications
- hypersensitivity to the components
of the drug;
- severe renal failure (creatinine
clearance <30 ml/min)
- severe liver failure;
- children and adolescents under 18
years of age.
Method of administration and dosage
Orally, without chewing, with a small
amount of liquid.
Adults
and children over 12 years of age are prescribed the
drug orally at 250 mg once a day.
The recommended duration of treatment
for:
dermatomycosis
of the feet
(interdigital, plantar or sock-type) - 2-6 weeks;
dermatomycosis
of the trunk,
shins - 2-4 weeks;
skin
candidiasis - 2-4
weeks. Complete disappearance of infection manifestations and complaints
associated with it may occur no earlier than several weeks after mycological
cure.
Onychomycosis
of the hands and feet – 6-12
weeks. Some patients (in case of damage to the big toe), who have a reduced
rate of nail growth, may require longer treatment. The optimal clinical effect
is observed several months after mycological cure and cessation of therapy.
This is determined by the period of time required for healthy nail growth.
Special instructions and precautions
Before using the drug, consult a
doctor.
It is not recommended to prescribe
the drug to patients with chronic or acute liver diseases. Before prescribing,
it is necessary to evaluate previous liver diseases. There is a risk of
developing hepatotoxicity in patients with or without liver diseases in the
medical history. The patient should be warned of the need to immediately
contact a doctor if the following symptoms appear: unexplained persistent
nausea, fatigue, vomiting, loss of appetite, jaundice, pain in the right hypochondrium,
dark urine or light stool. If such symptoms appear, it is necessary to
immediately stop taking the drug and conduct a liver function test
(determination of ALT, AST activity).
The drug should be used with caution
in renal failure, alcoholism, blood diseases, tumors, metabolic diseases,
vascular pathologies of the extremities, psoriasis.
Application during pregnancy and during breastfeeding
During pregnancy, the drug can be
used only if the expected positive effect for the mother outweighs the potential
risk to the fetus. If use during lactation is necessary, breastfeeding should
be discontinued.
Side effect
Terfil is generally well tolerated. Side effects
are usually mild or moderate and transient.
From the digestive system: a feeling of fullness in the stomach, loss of
appetite, dyspepsia, nausea, mild abdominal pain, diarrhea, flatulence, taste
disturbances, including their loss (recovery occurs within a few weeks after
stopping treatment).
From the musculoskeletal
system: arthralgia,
myalgia.
From the hematopoietic system: agranulocytosis, thrombocytopenia, neutropenia.
Rare: hepatobiliary disorders (primarily associated
with cholestasis), liver failure, asymptomatic increase in liver transaminases,
in case of hepatobiliary dysfunction, treatment with the drug should be
discontinued.
Allergic reactions: urticaria, rash, itching; very rare - toxic
epidermal necrolysis (Lyell's syndrome), anaphylactoid reactions, malignant
exudative erythema (Stevens-Johnson syndrome).
If a progressive skin rash develops, treatment
with terbinafine should be discontinued.
If any of the side effects
listed in the instructions worsen, or you notice any other side effects not
listed in the instructions, tell your doctor.
Interaction with other medicinal products
Terbinafine
has very little in vitro ability to
inhibit or increase the clearance of most drugs that are metabolized by the
cytochrome P450 system (e.g. cyclosporine, terfenadine, tolbutamide, triazolam,
or oral contraceptives).
Menstrual
irregularities may occur with concomitant use of terbinafine and oral
contraceptives.
The total
clearance of terbinafine may be accelerated by drugs that induce cytochrome
P450 enzymes (e.g. rifampicin) and may be slowed by drugs that inhibit the
cytochrome P450 system (e.g. cimetidine). Therefore, if it is necessary to use
these drugs concomitantly with terbinafine, a dose adjustment of the latter may
be necessary.
Terbinafine
may enhance the effects of caffeine (when administered intravenously) or
increase its plasma concentration.
Terbinafine
does not affect the clearance of antipyrine, digoxin, warfarin.
Symptoms:
headache, nausea,
stomach pain and dizziness.
Treatment:
administration of
activated charcoal and gastric lavage, use of symptomatic supportive therapy if
necessary.
Storage
conditions
Store in a dry, dark place at a
temperature below 30°C.
Keep out of reach of children!
Shelf life
2 years. Do not use after the
expiration date stated on the package.
Vacation conditions
Dispensed by prescription.
Release form
10 tablets in an aluminum foil blister. 1 blister together with instructions for use in a cardboard box.