Bioequivalence and Bioavailability of an Orodispersible Tablet of Sildenafil Citrate in Healthy Chinese Male Subjects
A similar study reported a consistent result, with a risk estimate of 2.27 (95% CI 0.99, 5.20). Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies.Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [ see Adverse Reactions (6.2)].Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals who have already experienced NAION are at increased risk of NAION recurrence. Therefore, PDE5 inhibitors, including sildenafil citrate, should be used with caution in these patients and only when the anticipated benefits outweigh the risks. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including sildenafil citrate, for this uncommon condition.There are no controlled clinical data on the safety or efficacy of sildenafil citrate in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution.5.4 Hearing LossPhysicians should advise patients to stop taking PDE5 inhibitors, including sildenafil citrate, and seek prompt medical attention in the event of sudden decrease or loss of hearing. These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including sildenafil citrate. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors [ see Adverse Reactions ( 6.1, 6.2) ].5.5 Hypotension when Co-administered with Alpha-blockers or Anti-hypertensivesAlpha-blockersCaution is advised when PDE5 inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including sildenafil citrate, and alpha-adrenergic blocking agents are both vasodilators with blood pressure lowering effects.When vasodilators are used in combination, an additive effect on blood pressure may occur. In some patients, concomitant use of these two drug classes can lower blood pressure significantly [ see Drug Interactions (7.2)and Clinical Pharmacology (12.2)] leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting).Consideration should be given to the following:Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors.
8. Use In Specific Populations
12.3 Pharmacokinetics
Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor.In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose [ see Dosage and Administration (2.3)].In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose. Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor.Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs.Anti-hypertensivesSildenafil citrate has systemic vasodilatory properties and may further lower blood pressure in patients taking anti-hypertensive medications.In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and sildenafil citrate, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted [ see Drug Interactions (7.3)and Clinical Pharmacology (12.2)].5.6 Adverse Reactions with the Concomitant Use of RitonavirThe concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If sildenafil citrate is prescribed to patients taking ritonavir, caution should be used.
| Use Case | Description | Typical Dosage | Onset of Action | Duration |
|---|---|---|---|---|
| Erectile Dysfunction | Helps achieve and maintain erections during sex | 125 mg | 30-60 minutes | Up to 4-6 hours |
| Pulmonary Hypertension | Relieves high blood pressure in lung arteries | 125 mg | 15-30 minutes | 4-6 hours |
| Off-Label Uses | Potential uses in other vascular conditions | Varies | Varies | Varies |
Data from subjects exposed to high systemic levels of sildenafil are limited. Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200 to 800 mg). To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended [ see Dosage and Administration (2.4), Drug Interactions (7.4), and Clinical Pharmacology (12.3)].5.7 Combination with other PDE5 Inhibitors or Other Erectile Dysfunction TherapiesThe safety and efficacy of combinations of sildenafil tablets, 25 mg, 50 mg and 100 mg with other PDE5 Inhibitors, including sildenafil tablets, 20 mg or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied. Such combinations may further lower blood pressure. Therefore, the use of such combinations is not recommended.5.8 Effects on BleedingThere have been postmarketing reports of bleeding events in patients who have taken sildenafil citrate. A causal relationship between sildenafil citrate and these events has not been established.
- Sildenafil tablets 125 mg are available by prescription only.
- They work by inhibiting the PDE5 enzyme.
- Do not mix sildenafil with alcohol to avoid adverse effects.
- Use with caution if you have heart or liver conditions.
- Sildenafil may interact with certain antibiotics.
- Be aware of potential side effects like flushing.
- Take sildenafil about 30-60 minutes before activity.
- Avoid using grapefruit juice while on sildenafil.
In humans, sildenafil citrate has no effect on bleeding time when taken alone or with aspirin. However, in vitro studies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor). In addition, the combination of heparin and sildenafil citrate had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans.The safety of sildenafil citrate is unknown in patients with bleeding disorders and patients with active peptic ulceration.5.9 Counseling Patients About Sexually Transmitted DiseasesThe use of sildenafil citrate offers no protection against sexually transmitted diseases.
| Product | Dosage | Quantity + Bonus | Price | |
|---|---|---|---|---|
| Kamagra Oral Jelly | 100mg | 30 + 5 Sachets | 136.20€ 129.71€ | |
| Kamagra Oral Jelly | 100mg | 10 Sachets | 54.55€ 51.95€ | |
| Viagra Generic | 25mg | 30 + 4 Pills | 47.97€ 45.69€ | |
| Kamagra Soft Tabs | 100mg | 84 + 4 Pills | 233.05€ 221.95€ | |
| Kamagra Polo | 100mg | 180 + 8 Pills | 446.52€ 425.26€ | |
| Kamagra Soft Tabs | 100mg | 20 Pills | 79.79€ 75.99€ | |
| Viagra Generic | 50mg | 10 Pills | 26.87€ 25.59€ | |
| Kamagra | 100mg | 12 Pills | 55.64€ 52.99€ | |
| Viagra Generic | 50mg | 270 + 8 Pills | 198.48€ 189.03€ | |
| Viagra Generic | 150mg | 120 + 8 Pills | 177.58€ 169.12€ | |
| Viagra Generic | 50mg | 120 + 6 Pills | 129.64€ 123.47€ |
Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered.
6. Adverse Reactions/Side Effects
Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor.Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs.Anti-hypertensivesSildenafil citrate has systemic vasodilatory properties and may further lower blood pressure in patients taking anti-hypertensive medications.In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and sildenafil citrate, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted [ see Drug Interactions (7.3)and Clinical Pharmacology (12.2)].5.6 Adverse Reactions with the Concomitant Use of RitonavirThe concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If sildenafil citrate is prescribed to patients taking ritonavir, caution should be used. Data from subjects exposed to high systemic levels of sildenafil are limited. Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200 to 800 mg). To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended [ see Dosage and Administration (2.4), Drug Interactions (7.4), and Clinical Pharmacology (12.3)].5.7 Combination with other PDE5 Inhibitors or Other Erectile Dysfunction TherapiesThe safety and efficacy of combinations of sildenafil tablets, 25 mg, 50 mg and 100 mg with other PDE5 Inhibitors, including sildenafil tablets, 20 mg or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied.
8.1 Pregnancy
Such combinations may further lower blood pressure. Therefore, the use of such combinations is not recommended.5.8 Effects on BleedingThere have been postmarketing reports of bleeding events in patients who have taken sildenafil citrate. A causal relationship between sildenafil citrate and these events has not been established. In humans, sildenafil citrate has no effect on bleeding time when taken alone or with aspirin. However, in vitro studies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor). There is sildenafil cenforce a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. The evaluation of erectile dysfunction should include a determination of potential underlying causes and the identification of appropriate treatment following a complete medical assessment. Sildenafil citrate has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 8.4/5.5 mmHg), [ see Clinical Pharmacology (12.2)].
| Interaction | Effect | Management Tips |
|---|---|---|
| Nitrates | Severe hypotension, danger to life | Avoid combination |
| Alpha-blockers | Risk of hypotension | Use with caution, monitor blood pressure |
| CYP3A4 inhibitors | Increased sildenafil levels, risk of side effects | Dose adjustments may be needed |
| Other PDE-5 inhibitors | Increased risk of adverse effects | Use separate medications |
While this normally would be expected to be of little consequence in most patients, prior to prescribing sildenafil citrate, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Use with caution in patients with the following underlying conditions which can be particularly sensitive to the actions of vasodilators including sildenafil citrate – those with left ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis) and those with severely impaired autonomic control of blood pressure.
- Sildenafil tablets are classified as phosphodiesterase inhibitors.
- They are quick-acting but effects vary by individual.
- Avoid taking with other erectile dysfunction medications.
- Liver or kidney impairment may require dose adjustments.
- Do not use sildenafil during sexual activity if unadvised.
- Safe sexual activity involves knowing your health status.
- Window for maximum effectiveness is around 1 hour before.
- Avoid excessive physical exertion after taking sildenafil.
There are no controlled clinical data on the safety or efficacy of sildenafil citrate in the following groups; if prescribed, this should be done with caution. Patients who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; Patients with resting hypotension (BP <90/50 mmHg) or hypertension (BP >170/110 mmHg); Patients with cardiac failure or coronary artery disease causing unstable angina. Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of sildenafil tablets. If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result.
2.2 Use with Food
In addition, the combination of heparin and sildenafil citrate had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans.The safety of sildenafil citrate is unknown in patients with bleeding disorders and patients with active peptic ulceration.5.9 Counseling Patients About Sexually Transmitted DiseasesThe use of sildenafil citrate offers no protection against sexually transmitted diseases. Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered. There is sildenafil cenforce a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. The evaluation of erectile dysfunction should include a determination of potential underlying causes and the identification of appropriate treatment following a complete medical assessment. Sildenafil citrate has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 8.4/5.5 mmHg), [ see Clinical Pharmacology (12.2)].
Jet lag research
While this normally would be expected to be of little consequence in most patients, prior to prescribing sildenafil citrate, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Use with caution in patients with the following underlying conditions which can be particularly sensitive to the actions of vasodilators including sildenafil citrate – those with left ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis) and those with severely impaired autonomic control of blood pressure. There are no controlled clinical data on the safety or efficacy of sildenafil citrate in the following groups; if prescribed, this should be done with caution. Patients who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; Patients with resting hypotension (BP <90/50 mmHg) or hypertension (BP >170/110 mmHg); Patients with cardiac failure or coronary artery disease causing unstable angina. Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of sildenafil tablets. Sildenafil citrate 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 anemia, multiple myeloma, or leukemia). However, there are no controlled clinical data on the safety or efficacy of sildenafil citrate in patients with sickle cell or related anemias. Physicians should advise patients to stop use of all phosphodiesterase type 5 (PDE5) inhibitors, including sildenafil citrate, and seek medical attention in the event of a sudden loss of vision in one or both eyes.
8.6 Patients with Hepatic Impairment
If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result. Sildenafil citrate 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 anemia, multiple myeloma, or leukemia). However, there are no controlled clinical data on the safety or efficacy of sildenafil citrate in patients with sickle cell or related anemias. Physicians should advise patients to stop use of all phosphodiesterase type 5 (PDE5) inhibitors, including sildenafil citrate, and seek medical attention in the event of a sudden loss of vision in one or both eyes. Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies.
Is 20 or 25mg Sildenafil Enough for ED?
Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [ see Adverse Reactions (6.2)]. Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including sildenafil citrate, for this uncommon condition. There are no controlled clinical data on the safety or efficacy of sildenafil citrate in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution. Physicians should advise patients to stop taking PDE5 inhibitors, including sildenafil citrate, and seek prompt medical attention in the event of sudden decrease or loss of hearing. Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies. Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [ see Adverse Reactions (6.2)]. Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including sildenafil citrate, for this uncommon condition. There are no controlled clinical data on the safety or efficacy of sildenafil citrate in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution. Physicians should advise patients to stop taking PDE5 inhibitors, including sildenafil citrate, and seek prompt medical attention in the event of sudden decrease or loss of hearing.
7.3 Amlodipine
A similar study reported a consistent result, with a risk estimate of 2.27 (95% CI 0.99, 5.20). Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies.Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [ see Adverse Reactions (6.2)].Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals who have already experienced NAION are at increased risk of NAION recurrence. Therefore, PDE5 inhibitors, including sildenafil citrate, should be used with caution in these patients and only when the anticipated benefits outweigh the risks. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including sildenafil citrate, for this uncommon condition.There are no controlled clinical data on the safety or efficacy of sildenafil citrate in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution.5.4 Hearing LossPhysicians should advise patients to stop taking PDE5 inhibitors, including sildenafil citrate, and seek prompt medical attention in the event of sudden decrease or loss of hearing.
Risk to travelers
These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including sildenafil citrate. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors [ see Adverse Reactions ( 6.1, 6.2) ].5.5 Hypotension when Co-administered with Alpha-blockers or Anti-hypertensivesAlpha-blockersCaution is advised when PDE5 inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including sildenafil citrate, and alpha-adrenergic blocking agents are both vasodilators with blood pressure lowering effects.When vasodilators are used in combination, an additive effect on blood pressure may occur. In some patients, concomitant use of these two drug classes can lower blood pressure significantly [ see Drug Interactions (7.2)and Clinical Pharmacology (12.2)] leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting).Consideration should be given to the following:Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors. Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor.In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose [ see Dosage and Administration (2.3)].In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose.