Neogra (sildenafile) 50mg; 100mg №2 caps
Drug for Erectile dysfunction treatment.
Composition: Active substance
(international nonpatent name): Sildenafil citrate - 50mg; 100mg;
Aiding substance: lactosa, starch, calcium or
magnesium stearate.
ATC code: GO4BEO3
Pharmacological
group: Drug for Erectile dysfunction treatment.
Pharmacological
operation:
Pharmacodynamics: Sildenafil citrate restores
erectile function disorder and ensures natural response on the sexual arousal.
Physiological mechanism of erection implies nitrogen oxide release at
time of sexual stimulation in the cavernous body. Nitrogen oxide activates
enzyme Guanulate cyclase, which causes cyclic
guanosine monophosphate (cGMP) level increase, relaxation of cavernous body smooth muscle and blood circulation strengthening in the genital organ. Sildenafil is a powerful and
selective inhibitor of (cGMP) specific phosphodiesterase 5 type (5
PDE), which is responsible for degradation of cGMP in the cavernous body. Sildenafil has no direct weakening impact on the cavernous
body, but
actively strengthens weakening effect of nitrogen oxide on this tissue. At time of
sexual arousal, nitrogen oxide releases in the cavernous body under the influence of Sildenafil, which suppresses 5
PDE and causes increase of cGMP level. Finally, smooth muscles of cavernous body
relax and blood flow strengthened in the cavernous body.
Sexual stimulation is necessary for desired pharmacological effect reveal of “Neo-Gra”. At one-time intake up to 100
mg dose, in healthy volunteers the preparation doesn't cause considerable
clinical changes on the electrocardiogram. In condition of confinement
to bed, maximum
reduction of systolic arterial pressure makes up 8,4 mm Hg. at time of
Sildenafil citrate 100mg intake. But diastolic pressure appropriate reduction -
on average 5,5 mm Hg. Decrease of arterial pressure is conditioned by
vasodilation effect, that can be related to cGMP level increase in the blood-vessel smooth muscles.
Sildenafil doesn’t influence on sight and prescription
contrast. In some patients, after 1 hour from 100mg dose intake is revealed
slight and transitive disorders of colour distinguish (blue/green); these
changes disappear after 2 hours.
Pharmacokinetics:
Sildenafil
citrate is quickly absorbed. After peroral intake on an empty stomach, preparation concentration in plasma reaches to peak during 30-120 minutes
(on average in 60 min) bioavailability 41%.
In case of intake together with fatty foods, its
absorption speed lowers. Tmax increases by 60 minutes and Cmax lowers by 29%.
96% of absorbed Sildenafil
citrate relates to plasma proteins.
Sildenafil mostly metabolizes by the influence of liver microsomal isoenzyme CYP 3A4 and CYP 2C9. Main metabolite formatted by
Sildenafil M-desmethylation further metabolizes and eliminated from the
organism together with excrement (approximately 80%), less together with urine
(approximately 13%).
Indication:Erectile dysfunction.
Contraindication:
·
Hypersensitivity towards any compounding components in the preparation.
·
Because the influence on nitrogen oxide and cGMP
change, Sildenafil
citrate strengthens hypotensive action of nitrates, so its use is
contraindicated in those patients who take
nitrogen oxide donator or nitrates in any
form.
Administration
and dosage rule:
Capsules of “Neo-Gra” is taken perorally.
Recommended dose – 50mg intake one hour before planned
sexual activity. Dose can be increased up to 100mg or decrease to 25mg, considering
preparation resistance and efficiency. Maximum recommended dose 100mg. Maximum
recommended usage frequency – one time intake in a day.
Elderly people and patients who have liver and kidney
functional disorder are recommended the same scheme of usage. “Neo-Gra” isn’t
used in children.
Side effects: Side effects caused by
Sildenafil citrate is moderate or light character. There may develop:
dizziness, headache, vasodilation, hypotension, asthenia, nasal breathing
difficulty, lacrimation, light and colour perception, exact sight disorder,
dyspepsia, diarrhea, nausea, abdominalgiya, lumbodynia, arthralgia, myalgia. Muscle hypertonicity,
insomnia, dyspnea, rash on the skin, prolonged and painful erection.
Safety measures: For erection disorder
diagnostic, determining its possible reasons and adequate treatment, it is
necessary to collect full medical anamnesis and make comprehensive physical
research. Sexual activity is a risk at time of heart disease. Before beginning any therapy at time of
erection disorder, a doctor should research cardiovascular system.
Safety and efficiency of “Neo-Gra” in combination with
other therapeutic agents that are used for erection disorder treatment isn’t
learned, that’s why similar combinations aren’t recommended.
Erection disorder treating preparations is used safely
for patients who have genital organ anatomic deformation (angulation, Cavernous fibrosis or peyronie’s
disease)
or patients who have multiple myeloma, drepancytic anemia or leukemia.
Small proportions of patients with innate pigmented retinitis
have retina phosphodiesterase activity hereditary disorders. Sildenafil is used
safely in such patient, because there aren’t data about preparation.
Interaction with
other preparations: Cimetidine (800mg) represents nonspecific
inhibitor of CYP3A4, taking together with “Neo-Gra” causes increase of Sildenafil
concentration in plasma by 56%. Populate pharmacokinetic analysis of clinical
studies results showed reduction of Sildenafil clearance at simultaneous use of
“Neo-Gra” CYP3A4 inhibitor (such as Ketoconazole, Erythromycin, Cimetidine). Though,
frequency of adverse events in these patients did not increase.
Take Antacids once (magnesium
hydroxide/aluminum hydroxide) doesn’t influence on Sildenafil bioavailability.
According to the data of populate pharmacokinetic analysis CYP2C9 inhibitors
(such as Tolbutamide, Warfarin), CYP2D6 inhibitors (such as selective
serotonin re-uptake inhibitors, tricyclic antidepressant), thiazide and thiazide
diuretics, ansiform and potassium-sparing diuretic, calcium antagonist, beta
blockers and CYP450 inhibitors (such as Rifampicin, barbiturates) don’t influence on Sildenafil pharmacokinetics.
Pregnancy and
lactation period: “Neo-Gra” isn’t used in women.
Reproductive researches implemented in rats and rabbits showed that peroral usage
of Sildenafil doesn’t cause teratogenic action, doesn’t impact on
reproductive function and doesn’t cause fetus postnatal and new born
development disorder. Single intake of 100 mg Neo-Gra in healthy people doesn’t
change sperm mobility and morphology.
Influence on vehicle and mechanisms management: Management
of vehicles and mechanisms doesn’t require protecting special security
measures.
Overdose: Overdose of
Sildenafil (up to
800 mg) reveals the same side effects, as small dose intake of preparation, but
overdose increases frequency of side effects reveal. In case of need there is
carried out symptomatic treatment.
Production form: Primary package: 2 capsules on blister;
Secondary package: one blister
in a carton box.
Shelf-life: 2 years.
Storage conditions: Store at dry, protected from light and
inaccessible for children place, at room temperature.
Issue: Pharmaceutical product
group III - issued without doctor's prescription.
