Viamax 50mg

Tablet
Sildenafil Citrate
Unimed Unihealth MFG. Ltd

Other Strength:
- Viamax 25mg
- Viamax 100mg

Alternative:
- Enegra 50mg
- Silagra 50mg
- Vigorex 50mg
- Enigma 50mg
- Adegra 50mg
- X-Cite 50mg
- Veagra 50mg
- Starfil 50mg



Viamax
Presentation
Viamax 25: Blue, round shaped, film coated tablet; each tablet contains Sildenafil Citrate INN equivalent to Sildenafil 25mg.
Viamax 50: Blue, diamond shaped, film coated tablet; each tablet contains Sildenafil Citrate INN equivalent to Sildenafil 50mg.
Viamax 100: Blue, barrel shaped, film coated tablet; each tablet contains Sildenafil Citrate INN equivalent to Sildenafil 100mg.

Indications
Treatment of men with erectile dysfunction, which is the inability to achieve or maintain a penile erection sufficient for satisfactory sexual performance. In order for Sildenafil Citrate to be effective, sexual stimulation is required.

Dosage and administration
For oral use.
Use in adults: The recommended dose is 50mg (one Viamax 50 tablet) taken as needed approximately one hour before sexual activity. Based on efficacy and toleration, the dose may be increased to 100mg (one Viamax 100 tablet) or decreased to 25mg (one Viamax 25 tablet). The maximum recommended dose is 100 mg. The maximum recommended dosing frequency is once per day. If Viamax (Sildenafil Citrate tablet) is taken with food, the onset of activity may be delayed compared to the fasted state.

Use in the elderly: Dosage adjustments are not required in elderly patients. Use in patients with impaired renal function: The dosing recommendations described in “Use in adults” apply to patients with mild to moderate renal impairment (creatinine clearance = 30-80
ml/min). Since Sildenafil clearance is reduced in patients with severe renal impairment (creatinine clearance < 30 ml/min) a 25mg dose should be considered. Based on efficacy and toleration, the dose may be increased to 50mg and 100mg. Use in patients with impaired hepatic function: Since Sildenafil clearance is reduced in patients with hepatic impairment (e.g. cirrhosis) a 25mg dose should be considered. Based on efficacy and toleration, the dose may be increased to 50mg and 100mg. Use in children and adolescents: Sildenafil Citrate is not indicated for individuals below 18 years of age.

Use in patients using other medicines: With the exception of Ritonavir for which coadministration with Sildenafil is not advised a starting dose of 25mg should be considered in patients receiving concomitant treatment with CYP3A4 inhibitors. In order to minimise the potential for developing postural hypotension, patients should be stable on Alpha-blocker therapy prior to initiating Sildenafil treatment. In addition, initiation of Sildenafil at a dose of 25 mg should be considered.

Contra-indications, warnings, etc
Contra-indications: Hypersensitivity to Sildenafil Citrate. Consistent with its known effects on the Nitric Oxide/cyclic guanosine monophosphate (cGMP) pathway, Sildenafil was shown to potentiate the hypotensive effects of nitrates, and its co-administration with Nitric Oxide donors (such as Amyl Nitrite) or Nitrates in any form is therefore contraindicated. Agents for the treatment of erectile dysfunction, including Sildenafil, should not be used in men for whom sexual activity is inadvisable (e.g. patients with severe cardiovascular disorders such as unstable angina or severe cardiac failure). Sildenafil Citrate is contraindicated in patients who have loss of vision in one eye because of non-arteritic anterior ischaemic optic neuropathy (NAION), regardless of whether this episode was in connection or not with previous PDE5 inhibitor exposure. The safety of Sildenafil has not been studied in the following sub-groups of patients and its use is therefore contraindicated: severe hepatic impairment, hypotension (blood pressure < 90/50 mmHg), recent history of stroke or myocardial infarction and known hereditary degenerative retinal disorders such as retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases). Precautions and warnings: A medical history and physical examination should be undertaken to diagnose erectile dysfunction and determine potential underlying causes, before pharmacological treatment is considered. Prior to initiating any treatment for erectile dysfunction, physicians should consider the cardiovascular status of their patients, since there is a degree of cardiac risk associated with sexual activity. Sildenafil has vasodilator properties, resulting in mild and transient decreases in blood pressure. Prior to
prescribing Sildenafil,
physicians should carefully consider whether their patients with certain underlying conditions could be adversely affected by such vasodilatory effects, especially in combination with sexual activity. Patients with increased susceptibility to vasodilators include those with left ventricular
outflow obstruction (e.g., aortic stenosis, hypertrophic obstructive cardiomyopathy), or those with the rare syndrome of multiple system atrophy manifesting as severely impaired autonomic control of blood pressure. Sildenafil Citrate tablet potentiates the hypotensive effect of Nitrates. Serious cardiovascular events, including myocardial infarction, unstable angina, sudden cardiac death, ventricular arrhythmia, cerebrovascular haemorrhage, transient ischaemic attack, hypertension and hypotension have been reported in post-marketing survey with the use of Sildenafil. Most, but not all, of these patients had pre-existing cardiovascular risk factors. Many events were reported to occur during or shortly after sexual intercourse and a few were reported to occur shortly after the use of Sildenafil without sexual activity. It is not possible to determine whether these events are related directly to these factors or to other factors. Agents for the treatment of erectile dysfunction, including Sildenafil, should be used with caution in patientswith anatomical deformation of the penis (such as angulation, cavernosal fibrosis or Peyronie’s disease), or in patients who have conditions which may
predispose them to priapism (such as sickle cell anaemia, multiple myeloma or leukaemia). The safety and efficacy of combinations of Sildenafil with other treatments for erectile dysfunction have not been studied. Therefore the use of such combinations is not recommended. Visual defects and cases of non-arteritic anterior ischaemic optic neuropathy have been reported in connection with the intake of Sildenafil andother PDE5 inhibitors. The patient should be advised that in case of sudden visual defect, heshould stop taking Sildenafil Citrate tablet and consult a physician immediately. Coadministration of Sildenafil with Ritonavir is not advised. Caution is advised when Sildenafil is administered to patients taking an Alpha-blocker, as the coadministration may lead to symptomatic hypotension in a few susceptible individuals. This is most likely to occur within 4 hours post Sildenafil dosing. In order to minimise the potential for developing postural hypotension, patients should be hemodynamically stable on Alpha-blocker therapy prior to initiating Sildenafil treatment. Initiation of Sildenafil at a dose of 25 mg should be considered. In addition, physicians should advise patients what to do in the event of postural hypotensive symptoms. Studies with human platelets indicate that Sildenafil potentiates the antiaggregatory
effect of Sodium Nitroprusside in vitro. There is no safety information on the administration of Sildenafil to patients with bleeding disorders or active peptic ulceration. Therefore Sildenafil should be administered to these patients only after careful benefit-risk assessment. Sildenafil Citrate tablet is not indicated for use by women. Drug interactions: In vitro studies: Sildenafil metabolism is principally mediated by the cytochrome P450 (CYP) isoforms 3A4
(major route) and 2C9 (minor route). Therefore, inhibitors of these isoenzymes may reduce Sildenafil clearance. In vivo studies: Population pharmacokinetic analysis of clinical trial data indicated a reduction in Sildenafil clearance when co-administered with CYP3A4 inhibitors (such as Ketoconazole, Erythromycin, Cimetidine). Although no increased incidence of adverse events was observed in these patients, when Sildenafil is administered concomitantly with CYP3A4 inhibitors, a starting dose of 25mg should be considered. Coadministration of the HIV protease inhibitor Ritonavir, which is a highly potent P450 inhibitor, at steady state (500mg twice daily) with Sildenafil (100mg single dose) resulted in a 300% (4-fold) increase in Sildenafil Cmax and a 1,000% (11-fold) increase in Sildenafil plasma AUC. Sildenafil had no effect on ritonavir pharmacokinetics. Based on these pharmacokinetic results coadministration of Sildenafil with ritonavir is not advised and in any event the maximum dose of Sildenafil should under no circumstances exceed 25mg within 48 hours.Co- administration of the HIV protease inhibitor Saquinavir, a CYP3A4 inhibitor, at steady state (1200mg three times a day) with Sildenafil (100mg single dose) resulted in a 140% increase in Sildenafil Cmax and a 210% increase in Sildenafil AUC. Sildenafil had no effect on Saquinavir pharmacokinetics. Stronger CYP3A4 inhibitors such as Ketoconazole and Itraconazole would be expected to have greater effects. When a single 100mg dose of Sildenafil was administered with erythromycin, a specific CYP3A4 inhibitor, at steady state (500mg twice daily for 5 days), there
was a 182% increase in Sildenafil systemic exposure (AUC). In normal healthy male volunteers, there was no evidence of an effect of Azithromycin (500mg daily for 3 days) on the AUC, Cmax, Tmax, elimination rate constant, or subsequent half-life of Sildenafil or its principal circulating metabolite. Cimetidine (800mg), a cytochrome P450 inhibitor and non-specific CYP3A4 inhibitor,caused a 56% increase in plasma Sildenafil concentrations when co-administered with Sildenafil (50mg) to healthy volunteers. Grapefruit juice is a weak inhibitor of CYP3A4 gut wall metabolism and may give rise to modest increases in plasma levels of Sildenafil. Single doses of antacid (magnesium hydroxide/aluminium hydroxide) did not affect the bioavailability of Sildenafil. Although specific interaction studies were not conducted for all medicinal products, population pharmacokinetic analysis showed no effect of concomitant medication on Sildenafil pharmacokinetics when grouped as CYP2C9 inhibitors (such as Tolbutamide, Warfarin, Phenytoin), CYP2D6 inhibitors (such as selective serotonin reuptake inhibitors, tricyclic antidepressants), thiazide and related diuretics, loop and potassium sparing diuretics, angiotensin converting enzyme inhibitors, calcium channel blockers, beta-adrenoreceptor antagonists or inducers of CYP450 metabolism (such as Rifampicin, Barbiturates). Nicorandil is a hybrid of potassium channel activator and nitrate. Due to the nitrate component it has the potential to have serious interaction with Sildenafil. Effects of Sildenafil on other medicinal products- In vitro studies: Sildenafil is a weak inhibitor of the cytochrome P450 isoforms 1A2, 2C9, 2C19, 2D6, 2E1 and 3A4 (IC50 >150 ìM). Given Sildenafil peak plasma concentrations of approximately 1 ìM after recommended doses, it is unlikely that Sildenafil Citrate tablet will alter the clearance of substrates of these isoenzymes. There are no data on the interaction of Sildenafil and non-specific
phosphodiesterase inhibitors such as Theophylline or Dipyridamole. In vivo studies: Consistent with its known effects on the Nitric Oxide/cGMP pathway, Sildenafil was shown to potentiate the hypotensive effects of nitrates, and its co-administration with Nitric Oxide donors or nitrates in any form is therefore contraindicated. Concomitant administration of Sildenafil to patients taking Alpha-blocker therapy may lead to symptomatic hypotension in a few susceptible individuals. This is most likely to occur within 4 hours post Sildenafil dosing. In three specific drug-drug interaction studies, the Alpha-blocker Doxazosin (4 mg and 8 mg) and Sildenafil (25 mg, 50 mg, or 100 mg) were administered simultaneously to patients with benign prostatic hyperplasia (BPH) stabilized on Doxazosin therapy. In these study populations, mean additional reductions of supine blood pressure of 7/7 mmHg, 9/5 mmHg, and 8/4 mmHg, and mean additional reductions of standing blood pressure of 6/6 mmHg, 11/4 mmHg, and 4/5 mmHg, respectively, were observed. When Sildenafil and Doxazosin were administered simultaneously to patients stabilized on Doxazosin therapy, there were infrequent reports of patients who experienced symptomatic postural hypotension. These reports included dizziness and light-headedness, but not syncope. No significant interactions were shown when Sildenafil
(50mg) was co-administered with Tolbutamide (250mg) or Warfarin (40mg), both of which are metabolised by CYP2C9. Sildenafil (50mg) did not potentiate the increase in bleeding time caused by Acetyl Salicylic Acid (150mg). Sildenafil (50mg) did not potentiate the hypotensive effects of alcohol in healthy volunteers with mean maximum blood alcohol levels of 80 mg/dl. Pooling of the following classes of antihypertensive medication; diuretics, beta-blockers, ACE inhibitors, angiotensin II antagonists, antihypertensive medicinal products (vasodilator and centrally-acting), adrenergic neurone blockers, calcium channel blockers and Alpha-adrenoceptor blockers, showed no difference in the side effect profile in patients taking Sildenafil compared to placebo treatment. In a specific interaction study, where Sildenafil (100mg) was co-administered with Amlodipine in hypertensive patients, there was an additional reduction on supine systolic blood pressure of 8 mmHg. The corresponding additional reduction in supine diastolic blood pressure was 7 mmHg. These additional blood pressure reductions were of a similar magnitude to those seen when Sildenafil was administered alone to healthy volunteers. Use in pregnancy and lactation: Sildenafil Citrate tablet is not indicated for use by women. No elevant adverse effects were found in reproduction studies in rats and rabbits following oral
administration of Sildenafil. Effects on ability to drive and use machines: No studies on the effects on the ability to drive and use machines have been performed. As dizziness and altered vision were reported in clinical trials with Sildenafil, patients should be aware of how they react to Sildenafil Citrate tablet, before driving or operating machinery.
Side effect: The most commonly reported adverse reactions in clinical studies among Sildenafil treated patients were headache, flushing, dyspepsia, visual disorders, nasal congestion, dizziness and visual colour distortion. Below all medically important adverse reactions, which occurred in clinical trials at an incidence greater than placebo are listed by system organ class and frequency (very common (³1/10), common (³1/100 to £1/10), uncommon (³1/1,000 to <1/100), rare (³1/10,000 to, 1/1,000). In addition, the frequency of medically important adverse reactions reported from post-marketing experience is included as not known. Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness. Medicallyimportant adverse reactions reported at an incidence greater than placebo in controlled clinical studies and medically important adverse reactions reported through post-marketing surveillance are as follows- Immune system disorders- Rare: Hypersensitivity reactions. Nervous system disorders- Very common: Headache. Common: Dizziness. Uncommon: Somnolence, Hypoaesthesia. Rare: Cerebrovascular accident, Syncope. Not known: Transient ischaemic attack, Seizure, Seizure recurrence. Eye disorders- Common: Visual disorders, Visual colour distortion.

Uncommon: Conjunctival disorders, Eye disorders, Lacrimation disorders, Other eye disorders.

Not known: Non-arteritic anterior ischaemic optic neuropathy (NAION), Retinal vascular occlusion, Visual field defect. Ear and labyrinth disorders- Uncommon: Vertigo, Tinnitus. Rare: Deafness. Vascular disorders- Common: Flushing. Rare: Hypertension, Hypotension. Cardiac
disorders- Uncommon: Palpitations, Tachycardia. Rare: Myocardial infarction, Atrial fibrillation. Unknown: Ventricular arrhythmia, Unstable angina, Sudden cardiac death. Respiratory, thoracic and mediastinal disorders- Common: Nasal congestion. Rare: Epistaxis. Gastrointestinal disorders- Common: Dyspepsia. Uncommon: Vomiting, Nausea, Dry mouth. Skin, subcutaneous and soft tissue disorders- Uncommon: Skin rash. Not Known: Steven Johnson Syndrome (SJS), Toxic Epidermal Necrolysis (TEN). Musculoskeletal and connective tissue disorders- Uncommon: Myalgia. Reproductive system and breast disorders- Not known: Priapism, Prolonged erection. General disorders and administration site conditions- Uncommon: Chest pain, Fatigue. Investigations- Uncommon: Heart rate increased. Overdose: In single dose volunteer studies of doses up to 800mg, adverse reactions were similar to those seen at lower doses, but the incidence rates and severities were increased. Doses of 200mg did not result in increased efficacy but the incidence of adverse reactions (headache, flushing, dizziness, dyspepsia, nasal congestion, altered vision) was increased. In cases of overdose, standard supportive measures should be adopted as required. Renal dialysis is not expected to accelerate clearance as Sildenafil is highly bound to plasma proteins and not eliminated in the urine.

Pharmaceutical precautions
Store in a cool and dry place protected from light.

Packaging quantities
Viamax 25 tablet: Cartons containing 4 tablets in blisters.
Viamax 50 tablet: Cartons containing 4 tablets in blisters.
Viamax 100 tablet: Cartons containing 4 tablets in blisters.

এই পাতাটি ৩৭০ বার দেখা হয়েছে