Sildenafil Viasan-LF
Viasan-LF tablet 100 mg x10, ATX code: G04BE03 (Sildenafil) Active substance: sildenafil (sildenafil) USAN accepted for use in the USA
Dosage form
VIASAN-LF
tab., cover film-coated, 100 mg: 2, 4 or 10 pcs.reg. No.: LSR-008888/09 from 05.11.09 - Indefinitely
Release form, packaging and composition of Sildenafil
Film-coated tablets 1 tab.
sildenafil (in the form of citrate) 100 mg, Clinical and pharmacological group: Drug for the treatment of erectile dysfunction. PDE-5 inhibitor Pharmacotherapeutic group: Treatment of erectile dysfunction, PDE-5 inhibitor The scientific information provided is general and cannot be used to make a decision about the possibility of using a specific drug.
pharmachologic effect
Selective inhibitor of cycloguanosine monophosphate (cGMP)-specific PDE5. PDE5, responsible for the breakdown of cGMP, is found not only in the corpus cavernosum of the penis, but also in the vessels of the lungs.
Restores impaired erectile function and provides a natural response to sexual arousal. Sildenafil does not have a direct relaxing effect on the corpus cavernosum, but actively enhances the relaxing effect of nitric oxide on this tissue. During sexual arousal, local release of NO under the influence of sildenafil leads to inhibition of PDE5 and an increase in the level of cGMP in the corpus cavernosum, resulting in relaxation of smooth muscles and increased blood flow in the corpus cavernosum.
As a PDE5 inhibitor, sildenafil increases the content of cGMP in the smooth muscle cells of the pulmonary vessels and causes them to relax. In patients with pulmonary hypertension, taking sildenafil leads to dilation of the pulmonary vessels and, to a lesser extent, other vessels.
Sildenafil is selective for PDE5 in vitro. Its activity against PDE5 exceeds that against other known PDE isoenzymes: PDE6, which is involved in the transmission of light signals in the retina, by 10 times, PDE1 by 80 times, PDE2, PDE4, PDE7-PDE11 by more than 700 times. The activity of sildenafil against PDE5 is more than 4000 times greater than its activity against PDE3, a cAMP-specific PDE involved in heart contraction.
Sildenafil may cause mild and transient impairment of color discrimination (blue/green). The putative mechanism for color vision impairment is the inhibition of PDE6, which is involved in the process of light transmission in the retina. In vitro studies have shown that the effect of sildenafil on PDE6 is 10 times lower than its activity on PDE5.
Pharmacokinetics
After oral administration, sildenafil is rapidly absorbed. Absolute bioavailability averages 40% (25-63%). After a single oral dose of 100 mg, Cmax is 18 ng/ml and is achieved when taken on an empty stomach for 30-120 minutes. When taking sildenafil in combination with fatty foods, the absorption rate decreases, Tmax increases by 60 minutes, and Cmax decreases by an average of 29%. The Vd of sildenafil at steady state is on average 105 liters. Sildenafil and its main circulating N-desmethyl metabolite are approximately 96% bound to plasma proteins. Protein binding is independent of the total concentration of sildenafil. Less than 0.0002% of the dose (mean 188 ng) was detected in semen 90 minutes after sildenafil administration.
Sildenafil is metabolized mainly by the liver microsomal isoenzymes CYP3A4 (the main route) and CYP2C9.
The main circulating metabolite, which is formed as a result of N-desmethylation of sildenafil, undergoes further metabolism. In terms of selectivity of action on PDE, the metabolite is comparable to sildenafil, and its activity against PDE5 in vitro is approximately 50% of the activity of sildenafil itself. The concentration of the metabolite in plasma is approximately 40% of that of sildenafil. The N-desmethyl metabolite undergoes further metabolism, its terminal T1/2 is about 4 hours.
The total clearance of sildenafil from the body is 41 l/h, and T1/2 in the terminal phase is 3-5 hours. After oral administration, sildenafil is excreted in the form of metabolites mainly in feces (approximately 80% of the dose) and to a lesser extent in urine ( approximately 13% of the dose).
In elderly patients (65 years and older), the clearance of sildenafil is reduced, and the concentration of the free active substance in plasma is approximately 40% higher than its concentration in young (18-45 years) patients.
In case of mild (creatinine clearance 50-80 ml/min) and moderate (creatinine clearance 30-49 ml/min) renal failure, the pharmacokinetic parameters of sildenafil after a single oral dose (50 mg) do not change. In severe renal failure (creatinine clearance ≤30 ml/min), the clearance of sildenafil is reduced, which leads to an approximately twofold increase in AUC (100%) and Cmax (88%) compared to those with normal renal function in patients of the same age group.
In patients with liver cirrhosis (Child-Pugh class A and B), the clearance of sildenafil is reduced, resulting in an increase in AUC (84%) and Cmax (47%) compared with those with normal liver function in patients of the same age group .
Indications for the drug Sildenafil
Treatment of erectile dysfunction, characterized by the inability to achieve or maintain a penile erection sufficient for satisfactory sexual intercourse.
Pulmonary hypertension.
ICD-10 codes
Dosage regimen The method of administration and dosage regimen of a particular drug depend on its release form and other factors. The optimal dosage regimen is determined by the doctor. The compliance of the dosage form of a particular drug with the indications for use and dosage regimen should be strictly observed.
Treatment of erectile dysfunction: taken orally approximately 1 hour before planned sexual activity. A single dose is 50 mg. Taking into account effectiveness and tolerability, the dose can be increased to 100 mg or reduced to 25 mg. The maximum single dose is 100 mg. The maximum frequency of use is 1 time/day. For elderly patients over the age of 65 years and with concomitant renal or hepatic impairment, the dose is 25 mg.
Pulmonary hypertension: orally 20 mg 3 times a day with an interval of about 6-8 hours, regardless of meals. The maximum daily dose is 60 mg. In patients with impaired renal function, no dose adjustment is required, however, if tolerated poorly, the dose is reduced to 20 mg 2 times a day.
Side effect
From the side of the central nervous system: possible headache, hot flashes, dizziness, insomnia.
From the digestive system: possible dyspepsia, asthenia, diarrhea, abdominal pain, nausea.
From the musculoskeletal system: arthralgia, myalgia, increased muscle tone.
From the respiratory system: nasal congestion, pharyngitis, rhinitis, sinusitis, respiratory tract infections, breathing problems.
On the part of the organ of vision: changes in vision (mild and transient, mainly changes in the color of objects, as well as increased perception of light and impaired clarity of vision), conjunctivitis.
Other: possible flu-like syndrome, development of infectious diseases, symptoms of vasodilation, back pain, rash, urinary tract infections, prostate dysfunction, and in isolated cases - priapism.
Contraindications for use: Simultaneous use of nitric oxide donors or nitrates in any form, hypersensitivity to sildenafil.
Use for liver dysfunction For liver dysfunction, the dose is 25 mg.
Use for impaired renal function For impaired renal function, the dose is 25 mg.
Use in children Sildenafil is not used in patients under 18 years of age.
Use in elderly patients For elderly patients over 65 years of age, the dose is 25 mg.
special instructions
Before starting to take sildenafil for the treatment of erectile dysfunction, a cardiovascular examination should be performed.
Use with caution in patients with anatomical deformation of the penis (such as angulation, cavernous fibrosis or Peyronie's disease) and people with diseases that predispose to the development of priapism (such as sickle cell anemia, multiple myeloma or leukemia).
Should not be used in patients for whom sexual activity is undesirable.
Use with caution in patients with a tendency to bleeding, with peptic ulcer of the stomach and duodenum in the acute phase, with hereditary retinitis pigmentosa.
Sildenafil is not used in patients under 18 years of age.
Impact on the ability to drive vehicles and operate machinery
Sildenafil does not affect the ability to drive vehicles or operate machinery.
Drug interactions
With simultaneous use of CYP3A4 inhibitors (erythromycin, cimetidine), the clearance of sildenafil decreases and the concentration of sildenafil in the blood plasma increases.
With the simultaneous use of indinavir, saquinavir, ritonavir, the plasma Cmax and AUC of sildenafil increases, which is due to inhibition of the CYP3A4 isoenzyme under the influence of indinavir, saquinavir, ritonavir.
Stronger CYP3A4 inhibitors, such as ketoconazole or itraconazole, can be expected to increase plasma concentrations of sildenafil
When used simultaneously with nitrates, the hypotensive effect of nitrates is enhanced.
A case of the development of symptoms of rhabdomyolysis after a single dose of sildenafil in a patient receiving simvastatin has been described.
Sildenafil Viasan-LF tablet p o film 100 mg x10
Viasan-LF tablet 100 mg x10, ATX code: G04BE03 (Sildenafil) Active substance: sildenafil (sildenafil) USAN accepted for use in the USA
Dosage form
VIASAN-LF
tab., cover film-coated, 100 mg: 2, 4 or 10 pcs.reg. No.: LSR-008888/09 from 05.11.09 - Indefinitely
Release form, packaging and composition of Sildenafil
Film-coated tablets 1 tab.
sildenafil (in the form of citrate) 100 mg, Clinical and pharmacological group: Drug for the treatment of erectile dysfunction. PDE-5 inhibitor Pharmacotherapeutic group: Treatment of erectile dysfunction, PDE-5 inhibitor The scientific information provided is general and cannot be used to make a decision about the possibility of using a specific drug.
pharmachologic effect
Selective inhibitor of cycloguanosine monophosphate (cGMP)-specific PDE5. PDE5, responsible for the breakdown of cGMP, is found not only in the corpus cavernosum of the penis, but also in the vessels of the lungs.
Restores impaired erectile function and provides a natural response to sexual arousal. Sildenafil does not have a direct relaxing effect on the corpus cavernosum, but actively enhances the relaxing effect of nitric oxide on this tissue. During sexual arousal, local release of NO under the influence of sildenafil leads to inhibition of PDE5 and an increase in the level of cGMP in the corpus cavernosum, resulting in relaxation of smooth muscles and increased blood flow in the corpus cavernosum.
As a PDE5 inhibitor, sildenafil increases the content of cGMP in the smooth muscle cells of the pulmonary vessels and causes them to relax. In patients with pulmonary hypertension, taking sildenafil leads to dilation of the pulmonary vessels and, to a lesser extent, other vessels.
Sildenafil is selective for PDE5 in vitro. Its activity against PDE5 exceeds that against other known PDE isoenzymes: PDE6, which is involved in the transmission of light signals in the retina, by 10 times, PDE1 by 80 times, PDE2, PDE4, PDE7-PDE11 by more than 700 times. The activity of sildenafil against PDE5 is more than 4000 times greater than its activity against PDE3, a cAMP-specific PDE involved in heart contraction.
Sildenafil may cause mild and transient impairment of color discrimination (blue/green). The putative mechanism for color vision impairment is the inhibition of PDE6, which is involved in the process of light transmission in the retina. In vitro studies have shown that the effect of sildenafil on PDE6 is 10 times lower than its activity on PDE5.
Pharmacokinetics
After oral administration, sildenafil is rapidly absorbed. Absolute bioavailability averages 40% (25-63%). After a single oral dose of 100 mg, Cmax is 18 ng/ml and is achieved when taken on an empty stomach for 30-120 minutes. When taking sildenafil in combination with fatty foods, the absorption rate decreases, Tmax increases by 60 minutes, and Cmax decreases by an average of 29%. The Vd of sildenafil at steady state is on average 105 liters. Sildenafil and its main circulating N-desmethyl metabolite are approximately 96% bound to plasma proteins. Protein binding is independent of the total concentration of sildenafil. Less than 0.0002% of the dose (mean 188 ng) was detected in semen 90 minutes after sildenafil administration.
Sildenafil is metabolized mainly by the liver microsomal isoenzymes CYP3A4 (the main route) and CYP2C9.
The main circulating metabolite, which is formed as a result of N-desmethylation of sildenafil, undergoes further metabolism. In terms of selectivity of action on PDE, the metabolite is comparable to sildenafil, and its activity against PDE5 in vitro is approximately 50% of the activity of sildenafil itself. The concentration of the metabolite in plasma is approximately 40% of that of sildenafil. The N-desmethyl metabolite undergoes further metabolism, its terminal T1/2 is about 4 hours.
The total clearance of sildenafil from the body is 41 l/h, and T1/2 in the terminal phase is 3-5 hours. After oral administration, sildenafil is excreted in the form of metabolites mainly in feces (approximately 80% of the dose) and to a lesser extent in urine ( approximately 13% of the dose).
In elderly patients (65 years and older), the clearance of sildenafil is reduced, and the concentration of the free active substance in plasma is approximately 40% higher than its concentration in young (18-45 years) patients.
In case of mild (creatinine clearance 50-80 ml/min) and moderate (creatinine clearance 30-49 ml/min) renal failure, the pharmacokinetic parameters of sildenafil after a single oral dose (50 mg) do not change. In severe renal failure (creatinine clearance ≤30 ml/min), the clearance of sildenafil is reduced, which leads to an approximately twofold increase in AUC (100%) and Cmax (88%) compared to those with normal renal function in patients of the same age group.
In patients with liver cirrhosis (Child-Pugh class A and B), the clearance of sildenafil is reduced, resulting in an increase in AUC (84%) and Cmax (47%) compared with those with normal liver function in patients of the same age group .
Indications for the drug Sildenafil
Treatment of erectile dysfunction, characterized by the inability to achieve or maintain a penile erection sufficient for satisfactory sexual intercourse.
Pulmonary hypertension.
ICD-10 codes
Dosage regimen The method of administration and dosage regimen of a particular drug depend on its release form and other factors. The optimal dosage regimen is determined by the doctor. The compliance of the dosage form of a particular drug with the indications for use and dosage regimen should be strictly observed.
Treatment of erectile dysfunction: taken orally approximately 1 hour before planned sexual activity. A single dose is 50 mg. Taking into account effectiveness and tolerability, the dose can be increased to 100 mg or reduced to 25 mg. The maximum single dose is 100 mg. The maximum frequency of use is 1 time/day. For elderly patients over the age of 65 years and with concomitant renal or hepatic impairment, the dose is 25 mg.
Pulmonary hypertension: orally 20 mg 3 times a day with an interval of about 6-8 hours, regardless of meals. The maximum daily dose is 60 mg. In patients with impaired renal function, no dose adjustment is required, however, if tolerated poorly, the dose is reduced to 20 mg 2 times a day.
Side effect
From the side of the central nervous system: possible headache, hot flashes, dizziness, insomnia.
From the digestive system: possible dyspepsia, asthenia, diarrhea, abdominal pain, nausea.
From the musculoskeletal system: arthralgia, myalgia, increased muscle tone.
From the respiratory system: nasal congestion, pharyngitis, rhinitis, sinusitis, respiratory tract infections, breathing problems.
On the part of the organ of vision: changes in vision (mild and transient, mainly changes in the color of objects, as well as increased perception of light and impaired clarity of vision), conjunctivitis.
Other: possible flu-like syndrome, development of infectious diseases, symptoms of vasodilation, back pain, rash, urinary tract infections, prostate dysfunction, and in isolated cases - priapism.
Contraindications for use: Simultaneous use of nitric oxide donors or nitrates in any form, hypersensitivity to sildenafil.
Use for liver dysfunction For liver dysfunction, the dose is 25 mg.
Use for impaired renal function For impaired renal function, the dose is 25 mg.
Use in children Sildenafil is not used in patients under 18 years of age.
Use in elderly patients For elderly patients over 65 years of age, the dose is 25 mg.
special instructions
Before starting to take sildenafil for the treatment of erectile dysfunction, a cardiovascular examination should be performed.
Use with caution in patients with anatomical deformation of the penis (such as angulation, cavernous fibrosis or Peyronie's disease) and people with diseases that predispose to the development of priapism (such as sickle cell anemia, multiple myeloma or leukemia).
Should not be used in patients for whom sexual activity is undesirable.
Use with caution in patients with a tendency to bleeding, with peptic ulcer of the stomach and duodenum in the acute phase, with hereditary retinitis pigmentosa.
Sildenafil is not used in patients under 18 years of age.
Impact on the ability to drive vehicles and operate machinery
Sildenafil does not affect the ability to drive vehicles or operate machinery.
Drug interactions
With simultaneous use of CYP3A4 inhibitors (erythromycin, cimetidine), the clearance of sildenafil decreases and the concentration of sildenafil in the blood plasma increases.
With the simultaneous use of indinavir, saquinavir, ritonavir, the plasma Cmax and AUC of sildenafil increases, which is due to inhibition of the CYP3A4 isoenzyme under the influence of indinavir, saquinavir, ritonavir.
Stronger CYP3A4 inhibitors, such as ketoconazole or itraconazole, can be expected to increase plasma concentrations of sildenafil
When used simultaneously with nitrates, the hypotensive effect of nitrates is enhanced.
A case of the development of symptoms of rhabdomyolysis after a single dose of sildenafil in a patient receiving simvastatin has been described.
