Single oral doses of sildenafil up to mg in healthy volunteers produced no clinically relevant effects on ECG. After chronic dosing of 80 mg three times a day to patients with PAH, no clinically relevant effects on ECG were reported.
After chronic dosing of 80 mg three times a day sildenafil to healthy volunteers, the largest mean change from baseline in supine systolic and supine diastolic blood pressures was a decrease of 9. After chronic dosing of 80 mg three times a day sildenafil to patients with systemic hypertension , the mean change from baseline in systolic and diastolic blood pressures was a decrease of 9. After chronic dosing of 80 mg three times a day sildenafil to patients with PAH, lesser reductions than above in systolic and diastolic blood pressures were observed a decrease in both of 2 mmHg.
This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. An evaluation of visual function at doses up to mg revealed no effects of REVATIO on visual acuity , intraocular pressure , or pupillometry. Maximum observed plasma concentrations are reached within 30 to minutes median 60 minutes of oral dosing in the fasted state.
The mean steady state volume of distribution Vss for sildenafil is L, indicating distribution into the tissues. Protein binding is independent of total drug concentrations. The major circulating metabolite results from N-desmethylation of sildenafil, and is, itself, further metabolized. In patients with PAH, however, the ratio of the metabolite to sildenafil is higher. Both sildenafil and the active metabolite have terminal half-lives of about 4 hours.
A 10 mg dose of REVATIO Injection is predicted to provide a pharmacological effect of sildenafil and its N-desmethyl metabolite equivalent to that of a 20 mg oral dose.
Population Pharmacokinetics Age, gender, race, and renal and hepatic function were included as factors assessed in the population pharmacokinetic model to evaluate sildenafil pharmacokinetics in patients with PAH.
The dataset available for the population pharmacokinetic evaluation contained a wide range of demographic data and laboratory parameters associated with hepatic and renal function.
Missed Dose Take the missed dose as soon as possible. If it is almost time of the next intake just skip it and go back to your schedule. Overdose If you think you have overdosed the medicine seek emergency medical help at once. Storage Store the medicine at room temperature between C F away from children, pets, moisture and sunlight. Note The information presented at the site has a general character. Note please this information cannot be used for self-treatment and self diagnosis.
You should consult with your doctor or health care adviser regarding any specific instructions of your condition. The information is reliable, but we concede it could contain mistakes. We are not responsible for any direct, indirect, special or other damage caused by use of this information on the site and also for consequences of self-treatment. In the long term paediatric extension study, an increase in deaths was observed in patients administered doses higher than the recommended dose.
Therefore, doses higher than the recommended doses should not be used in paediatric patients with PAH see also sections 4. Retinitis pigmentosa The safety of sildenafil has not been studied in patients with known hereditary degenerative retinal disorders such as retinitis pigmentosa a minority of these patients have genetic disorders of retinal phosphodiesterases and therefore its use is not recommended. Vasodilatory action When prescribing sildenafil, physicians should carefully consider whether patients with certain underlying conditions could be adversely affected by sildenafil's mild to moderate vasodilatory effects, for example patients with hypotension, patients with fluid depletion, severe left ventricular outflow obstruction or autonomic dysfunction see section 4.
Cardiovascular risk factors In post-marketing experience with sildenafil for male erectile dysfunction, 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 temporal association 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.
Priapism Sildenafil should be used with caution in patients with 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.
Prolonged erections and priapism have been reported with sildenafil in post-marketing experience. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result see section 4. Vaso-occlusive crises in patients with sickle cell anaemia Sildenafil should not be used in patients with pulmonary hypertension secondary to sickle cell anaemia.
In a clinical study events of vaso-occlusive crises requiring hospitalisation were reported more commonly by patients receiving Revatio than those receiving placebo leading to the premature termination of this study. Visual events Cases of visual defects have been reported spontaneously in connection with the intake of sildenafil and other PDE5 inhibitors.
Cases of non-arteritic anterior ischaemic optic neuropathy, a rare condition, have been reported spontaneously and in an observational study in connection with the intake of sildenafil and other PDE5 inhibitors see section 4. In the event of any sudden visual defect, the treatment should be stopped immediately and alternative treatment should be considered see section 4. Alpha-blockers Caution is advised when sildenafil is administered to patients taking an alpha-blocker as the co-administration may lead to symptomatic hypotension in susceptible individuals see section 4.
In order to minimise the potential for developing postural hypotension, patients should be haemodynamically stable on alpha-blocker therapy prior to initiating sildenafil treatment. Physicians should advise patients what to do in the event of postural hypotensive symptoms.
Bleeding disorders 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. Vitamin K antagonists In pulmonary arterial hypertension patients, there may be a potential for increased risk of bleeding when sildenafil is initiated in patients already using a Vitamin K antagonist, particularly in patients with pulmonary arterial hypertension secondary to connective tissue disease.
Veno-occlusive disease No data are available with sildenafil in patients with pulmonary hypertension associated with pulmonary veno-occlusive disease.
However, cases of life threatening pulmonary oedema have been reported with vasodilators mainly prostacyclin when used in those patients. Consequently, should signs of pulmonary oedema occur when sildenafil is administered in patients with pulmonary hypertension, the possibility of associated veno-occlusive disease should be considered. Galactose intolerance Lactose monohydrate is present in the tablet film coat.
Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine. Use of sildenafil with bosentan The efficacy of sildenafil in patients already on bosentan therapy has not been conclusively demonstrated see sections 4. Concomitant use with other PDE5 inhibitors The safety and efficacy of sildenafil when co-administered with other PDE5 inhibitor products, including Viagra, has not been studied in PAH patients and such concomitant use is not recommended see section 4.
Therefore, inhibitors of these isoenzymes may reduce sildenafil clearance and inducers of these isoenzymes may increase sildenafil clearance. For dose recommendations, see sections 4.
In vivo studies Co-administration of oral sildenafil and intravenous epoprostenol has been evaluated see sections 4. The efficacy and safety of sildenafil co-administered with other treatments for pulmonary arterial hypertension eg, ambrisentan, iloprost has not been studied in controlled clinical trials.
Therefore, caution is recommended in case of co-administration. The safety and efficacy of sildenafil when co-administered with other PDE5 inhibitors has not been studied in pulmonary arterial hypertension patients see section 4. These were the only factors with a statistically significant impact on sildenafil pharmacokinetics in patients with pulmonary arterial hypertension. Sildenafil exposure was 5-fold higher at a dose of 80 mg three times a day compared to the exposure at a dose of 20 mg three times a day.
This concentration range covers the increase in sildenafil exposure observed in specifically designed drug interaction studies with CYP3A4 inhibitors except with the most potent of the CYP3A4 inhibitors eg, ketoconazole, itraconazole, ritonavir. CYP3A4 inducers seemed to have a substantial impact on the pharmacokinetics of sildenafil in pulmonary arterial hypertension patients, which was confirmed in the in-vivo interaction study with CYP3A4 inducer bosentan.
A population pharmacokinetic analysis of sildenafil data from adult PAH patients in clinical trials including a 12 week study to assess the efficacy and safety of oral sildenafil 20 mg three times a day when added to a stable dose of bosentan
© Copyright 2017 Revatio 20mg for erectile dysfunction / BUY ORDER Revatio (Sildenafil Citrate) cheap discount online for sale price cost 20 mg Revatio is prescribed for treatment of pulmonary hypertension and erectile..