WARNINGS AND PRECAUTIONS

Both of these subjects were protocol violators, one due to a low baseline standing SBP, and the other due to baseline orthostatic hypotension. Study 2: Sildenafil tablets with DoxazosinIn the second study, a single oral dose of sildenafil tablets 50 mg or matching placebo was administered in a 2-period crossover design to 20 generally healthy males with BPH. Following at least 14 consecutive days of doxazosin, sildenafil tablets 50 mg or matching placebo was administered simultaneously with doxazosin 4 mg (17 subjects) or with doxazosin 8 mg (3 subjects). The mean subject age in this study was 63.9 years.Twenty subjects received sildenafil tablets 50 mg, but only 19 subjects received matching placebo. One patient discontinued the study prematurely due to an adverse event of hypotension following dosing with sildenafil tablets 50 mg.

2.2 Use with Food

The mean subject age in this study was 66.4 years.Twenty-five subjects were screened. Two were discontinued after study period 1: one failed to meet pre-dose screening qualifications and the other experienced symptomatic hypotension as a moderately severe adverse event 30 minutes after dosing with open-label sildenafil tablets 50 mg. Of the twenty subjects who were ultimately assigned to treatment, a total of 13 subjects successfully completed dose period 1, and seven had successfully completed the previous doxazosin study (using sildenafil tablets 50 mg).For the 20 subjects who received sildenafil tablets 100 mg and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows:The mean profiles of the change from baseline in standing systolic blood pressure in subjects treated with doxazosin in combination with 100 mg sildenafil tablets or sildenafil cenforce matching placebo are shown in Figure 4.Figure 4: Mean Standing Systolic Blood Pressure Change from BaselineBlood pressure was measured after administration of sildenafil tablets at the same times as those specified for the previous doxazosin studies. There were three subjects who had a standing SBP of < 85 mmHg. All three were taking sildenafil tablets 100 mg, and all three reported mild adverse events at the time of reductions in standing SBP, including vasodilation and lightheadedness.

Sildenafil Citrate

There were four subjects with a decrease from baseline in standing systolic BP > 30 mmHg following sildenafil tablets 100 mg, one subject with a decrease from baseline in standing systolic BP > 30 mmHg following placebo and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both sildenafil tablets and placebo. While there were no severe adverse events potentially related to blood pressure reported in this study, one subject reported moderate vasodilatation after both sildenafil tablets 50 mg and 100 mg. There were no episodes of syncope reported in this study.Effect of Sildenafil Tablets on Blood Pressure When Co-administered with Anti-hypertensives: When sildenafil tablets 100 mg oral was co-administered with amlodipine, 5 mg or 10 mg oral, to hypertensive patients, the mean additional reduction on supine blood pressure was 8 mmHg systolic and 7 mmHg diastolic.Effect of Sildenafil Tablets on Blood Pressure When Co-administered with Alcohol: Sildenafil tablets (50 mg) did not potentiate the hypotensive effect of alcohol (0.5 g/kg) in healthy volunteers with mean maximum blood alcohol levels of 0.08%. The maximum observed decrease in systolic blood pressure was -18.5 mmHg when sildenafil was co-administered with alcohol versus -17.4 mmHg when alcohol was administered alone. The maximum observed decrease in diastolic blood pressure was -17.2 mmHg when sildenafil was co-administered with alcohol versus -11.1 mmHg when alcohol was administered alone.

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:

There were no reports of postural dizziness or orthostatic hypotension. The maximum recommended dose of 100 mg sildenafil was not evaluated in this study [see Drug Interactions(7.5)].Effects of Sildenafil Tablets on Cardiac Parameters:Single oral doses of sildenafil up to 100 mg produced no clinically relevant changes in the ECGs of normal male volunteers.Studies have produced relevant data on the effects of sildenafil tablets on cardiac output. In one small, open-label, uncontrolled, pilot study, eight patients with stable ischemic heart disease underwent Swan-Ganz catheterization. A total dose of 40 mg sildenafil was administered by four intravenous infusions.The results from this pilot study are shown in Table 3; the mean resting systolic and diastolic blood pressures decreased by 7% and 10% compared to baseline in these patients. Mean resting values for right atrial pressure, pulmonary artery pressure, pulmonary artery occluded pressure and cardiac output decreased by 28%, 28%, 20% and 7% respectively. This patient had been taking minoxidil, a potent vasodilator, during the study.For the 19 subjects who received both sildenafil tablets and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows:The mean profiles of the change from baseline in standing systolic blood pressure in subjects treated with doxazosin in combination with 50 mg sildenafil tablets or matching placebo are shown in Figure 3.Figure 3: Mean Standing Systolic Blood Pressure Change from BaselineBlood pressure was measured after administration of sildenafil tablets at the same times as those specified for the first doxazosin study. There were two subjects who had a standing SBP of < 85 mmHg. In these two subjects, hypotension was reported as a moderately severe adverse event, beginning at approximately 1 hour after administration of sildenafil tablets 50 mg and resolving after approximately 7.5 hours. There was one subject with a decrease from baseline in standing systolic BP >30mmHg following sildenafil tablets 50 mg and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both sildenafil tablets 50 mg and placebo.

There were no severe adverse events potentially related to blood pressure and no episodes of syncope reported in this study.Study 3: Sildenafil tablets with DoxazosinIn the third study, a single oral dose of sildenafil tablets 100 mg or matching placebo was administered in a 3-period crossover design to 20 generally healthy males with BPH. In dose period 1, subjects were administered open-label doxazosin and a single dose of sildenafil tablets 50 mg simultaneously, after at least 14 consecutive days of doxazosin. If a subject did not successfully complete this first dosing period, he was discontinued from the study. Subjects who had successfully completed the previous doxazosin interaction study (using sildenafil tablets 50 mg), including no significant hemodynamic adverse events, were allowed to skip dose period 1. Treatment with doxazosin continued for at least 7 days after dose period 1. Thereafter, sildenafil tablets 100 mg or matching placebo was administered simultaneously with doxazosin 4 mg (14 subjects) or doxazosin 8 mg (6 subjects) in standard crossover fashion. The mean subject age in this study was 66.4 years.Twenty-five subjects were screened. Two were discontinued after study period 1: one failed to meet pre-dose screening qualifications and the other experienced symptomatic hypotension as a moderately severe adverse event 30 minutes after dosing with open-label sildenafil tablets 50 mg. Of the twenty subjects who were ultimately assigned to treatment, a total of 13 subjects successfully completed dose period 1, and seven had successfully completed the previous doxazosin study (using sildenafil tablets 50 mg).For the 20 subjects who received sildenafil tablets 100 mg and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows:The mean profiles of the change from baseline in standing systolic blood pressure in subjects treated with doxazosin in combination with 100 mg sildenafil tablets or sildenafil cenforce matching placebo are shown in Figure 4.Figure 4: Mean Standing Systolic Blood Pressure Change from BaselineBlood pressure was measured after administration of sildenafil tablets at the same times as those specified for the previous doxazosin studies.

The numan take

There were three subjects who had a standing SBP of < 85 mmHg. All three were taking sildenafil tablets 100 mg, and all three reported mild adverse events at the time of reductions in standing SBP, including vasodilation and lightheadedness. There were four subjects with a decrease from baseline in standing systolic BP > 30 mmHg following sildenafil tablets 100 mg, one subject with a decrease from baseline in standing systolic BP > 30 mmHg following placebo and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both sildenafil tablets and placebo. While there were no severe adverse events potentially related to blood pressure reported in this study, one subject reported moderate vasodilatation after both sildenafil tablets 50 mg and 100 mg. There were no episodes of syncope reported in this study.Effect of Sildenafil Tablets on Blood Pressure When Co-administered with Anti-hypertensives: When sildenafil tablets 100 mg oral was co-administered with amlodipine, 5 mg or 10 mg oral, to hypertensive patients, the mean additional reduction on supine blood pressure was 8 mmHg systolic and 7 mmHg diastolic.Effect of Sildenafil Tablets on Blood Pressure When Co-administered with Alcohol: Sildenafil tablets (50 mg) did not potentiate the hypotensive effect of alcohol (0.5 g/kg) in healthy volunteers with mean maximum blood alcohol levels of 0.08%. The maximum observed decrease in systolic blood pressure was -18.5 mmHg when sildenafil was co-administered with alcohol versus -17.4 mmHg when alcohol was administered alone. The maximum observed decrease in diastolic blood pressure was -17.2 mmHg when sildenafil was co-administered with alcohol versus -11.1 mmHg when alcohol was administered alone.

There were no reports of postural dizziness or orthostatic hypotension.

The maximum recommended dose of 100 mg sildenafil was not evaluated in this study [see Drug Interactions(7.5)].Effects of Sildenafil Tablets on Cardiac Parameters:Single oral doses of sildenafil up to 100 mg produced no clinically relevant changes in the ECGs of normal male volunteers.Studies have produced relevant data on the effects of sildenafil tablets on cardiac output. In one small, open-label, uncontrolled, pilot study, eight patients with stable ischemic heart disease underwent Swan-Ganz catheterization. A total dose of 40 mg sildenafil was administered by four intravenous infusions.The results from this pilot study are shown in Table 3; the mean resting systolic and diastolic blood pressures decreased by 7% and 10% compared to baseline in these patients. Mean resting values for right atrial pressure, pulmonary artery pressure, pulmonary artery occluded pressure and cardiac output decreased by 28%, 28%, 20% and 7% respectively. Even though this total dosage produced plasma sildenafil concentrations which were approximately 2 to 5 times higher than the mean maximum plasma concentrations following a single oral dose of 100 mg in healthy male volunteers, the hemodynamic response to exercise was preserved in these patients.Table 3.

Hemodynamic Data in Patients with Stable Ischemic Heart Disease after Intravenous Administration of 40 mg of SildenafilIn a double-blind study, 144 patients with erectile dysfunction and chronic stable angina limited by exercise, not receiving chronic oral nitrates, were randomized to a single dose of placebo sildenafil 50 mg tab or sildenafil tablets 100 mg 1 hour prior to exercise testing. The primary endpoint was time to limiting angina in the evaluable cohort. The mean times (adjusted for baseline) to onset of limiting angina were 423.6 and 403.7 seconds for sildenafil (N=70) and placebo, respectively.

7.5 Alcohol

Both of these subjects were protocol violators, one due to a low baseline standing SBP, and the other due to baseline orthostatic hypotension. Study 2: Sildenafil tablets with DoxazosinIn the second study, a single oral dose of sildenafil tablets 50 mg or matching placebo was administered in a 2-period crossover design to 20 generally healthy males with BPH. Following at least 14 consecutive days of doxazosin, sildenafil tablets 50 mg or matching placebo was administered simultaneously with doxazosin 4 mg (17 subjects) or with doxazosin 8 mg (3 subjects). The mean subject age in this study was 63.9 years.Twenty subjects received sildenafil tablets 50 mg, but only 19 subjects received matching placebo. One patient discontinued the study prematurely due to an adverse event of hypotension following dosing with sildenafil tablets 50 mg.

Warnings for other groups

This patient had been taking minoxidil, a potent vasodilator, during the study.For the 19 subjects who received both sildenafil tablets and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows:The mean profiles of the change from baseline in standing systolic blood pressure in subjects treated with doxazosin in combination with 50 mg sildenafil tablets or matching placebo are shown in Figure 3.Figure 3: Mean Standing Systolic Blood Pressure Change from BaselineBlood pressure was measured after administration of sildenafil tablets at the same times as those specified for the first doxazosin study. There were two subjects who had a standing SBP of < 85 mmHg. In these two subjects, hypotension was reported as a moderately severe adverse event, beginning at approximately 1 hour after administration of sildenafil tablets 50 mg and resolving after approximately 7.5 hours. There was one subject with a decrease from baseline in standing systolic BP >30mmHg following sildenafil tablets 50 mg and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both sildenafil tablets 50 mg and placebo. There were no severe adverse events potentially related to blood pressure and no episodes of syncope reported in this study.Study 3: Sildenafil tablets with DoxazosinIn the third study, a single oral dose of sildenafil tablets 100 mg or matching placebo was administered in a 3-period crossover design to 20 generally healthy males with BPH.

Overall Rating

In dose period 1, subjects were administered open-label doxazosin and a single dose of sildenafil tablets 50 mg simultaneously, after at least 14 consecutive days of doxazosin. If a subject did not successfully complete this first dosing period, he was discontinued from the study. Subjects who had successfully completed the previous doxazosin interaction study (using sildenafil tablets 50 mg), including no significant hemodynamic adverse events, were allowed to skip dose period 1. Treatment with doxazosin continued for at least 7 days after dose period 1. Thereafter, sildenafil tablets 100 mg or matching placebo was administered simultaneously with doxazosin 4 mg (14 subjects) or doxazosin 8 mg (6 subjects) in standard crossover fashion. These results demonstrated that the effect of sildenafil tablets on the primary endpoint was statistically non-inferior to placebo.Effects of Sildenafil Tablets on Vision:At single oral doses of 100 mg and 200 mg, transient dose-related impairment of color discrimination was detected using the Farnsworth-Munsell 100-hue test, with peak effects near the time of peak plasma levels. This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. Subjects in the study reported this finding as difficulties in discriminating blue/green. An evaluation of visual function at doses up to twice the maximum recommended dose revealed no effects of sildenafil tablets on visual acuity, intraocular pressure, or pupillometry.Effects of Sildenafil Tablets on Sperm:There was no effect on sperm motility or morphology after single 100 mg oral doses of sildenafil tablets in healthy volunteers.12.3 PharmacokineticsSildenafil tablets are rapidly absorbed after oral administration, with a mean absolute bioavailability of 41% (range 25 to 63%). The pharmacokinetics of sildenafil are dose-proportional over the recommended dose range.

• Sildenafil tablets are often stored in their original packaging to avoid contamination.
• Use only the amount prescribed; more does not mean better results.
• Sildenafil helps improve erectile function but doesn’t increase libido.
• The tablets are designed for rapid and effective absorption.
• Always inform your doctor about existing health conditions before use.
• Some brands of sildenafil are marketed as "white tablets" for easy recognition.
• The medication can cause a mild increase in blood flow to other body parts.
• Avoid caffeine or heavy meals before taking sildenafil for better results.
• The safety and efficacy of sildenafil are supported by numerous clinical trials.
• Never take expired sildenafil tablets, as their safety can’t be guaranteed.
• Regular blood pressure checks are recommended when using sildenafil long-term.

It is eliminated predominantly by hepatic metabolism (mainly CYP3A4) and is converted to an active metabolite with properties similar to the parent, sildenafil. Both sildenafil and the metabolite have terminal half lives of about 4 hours.Mean sildenafil plasma concentrations measured after the administration of a single oral dose of 100 mg to healthy male volunteers is depicted below:Figure 5: Mean Sildenafil Plasma Concentrationsin Healthy Male Volunteers.Absorption and Distribution: Sildenafil tablets are rapidly absorbed.

Images for 100

Even though this total dosage produced plasma sildenafil concentrations which were approximately 2 to 5 times higher than the mean maximum plasma concentrations following a single oral dose of 100 mg in healthy male volunteers, the hemodynamic response to exercise was preserved in these patients.Table 3. Hemodynamic Data in Patients with Stable Ischemic Heart Disease after Intravenous Administration of 40 mg of SildenafilIn a double-blind study, 144 patients with erectile dysfunction and chronic stable angina limited by exercise, not receiving chronic oral nitrates, were randomized to a single dose of placebo sildenafil 50 mg tab or sildenafil tablets 100 mg 1 hour prior to exercise testing. The primary endpoint was time to limiting angina in the evaluable cohort. The mean times (adjusted for baseline) to onset of limiting angina were 423.6 and 403.7 seconds for sildenafil (N=70) and placebo, respectively. These results demonstrated that the effect of sildenafil tablets on the primary endpoint was statistically non-inferior to placebo.Effects of Sildenafil Tablets on Vision:At single oral doses of 100 mg and 200 mg, transient dose-related impairment of color discrimination was detected using the Farnsworth-Munsell 100-hue test, with peak effects near the time of peak plasma levels.

Clinical monitoring

This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. Subjects in the study reported this finding as difficulties in discriminating blue/green. An evaluation of visual function at doses up to twice the maximum recommended dose revealed no effects of sildenafil tablets on visual acuity, intraocular pressure, or pupillometry.Effects of Sildenafil Tablets on Sperm:There was no effect on sperm motility or morphology after single 100 mg oral doses of sildenafil tablets in healthy volunteers.12.3 PharmacokineticsSildenafil tablets are rapidly absorbed after oral administration, with a mean absolute bioavailability of 41% (range 25 to 63%). The pharmacokinetics of sildenafil are dose-proportional over the recommended dose range. It is eliminated predominantly by hepatic metabolism (mainly CYP3A4) and is converted to an active metabolite with properties similar to the parent, sildenafil.

How sildenafil is used

Both sildenafil and the metabolite have terminal half lives of about 4 hours.Mean sildenafil plasma concentrations measured after the administration of a single oral dose of 100 mg to healthy male volunteers is depicted below:Figure 5: Mean Sildenafil Plasma Concentrationsin Healthy Male Volunteers.Absorption and Distribution: Sildenafil tablets are rapidly absorbed. Maximum observed plasma concentrations are reached within 30 to 120 minutes (median 60 minutes) of oral dosing in the fasted state. When sildenafil tablets are taken with a high fat meal, the rate of absorption is reduced, with a mean delay in T maxof 60 minutes and a mean reduction in C maxof 29%. The mean steady state volume of distribution (Vss) for sildenafil is 105 L, indicating distribution into the tissues. Maximum observed plasma concentrations are reached within 30 to 120 minutes (median 60 minutes) of oral dosing in the fasted state. When sildenafil tablets are taken with a high fat meal, the rate of absorption is reduced, with a mean delay in T maxof 60 minutes and a mean reduction in C maxof 29%.

• Sildenafil is classified as a prescription medication in most countries.
• Proper diagnosis of ED by a doctor is essential before using sildenafil.
• Sildenafil’s primary function is to facilitate normal erectile response.
• The drug's onset of action can vary among individuals.
• White sildenafil tablets are sometimes found in counterfeit markets.
• It’s advisable to start with the lowest effective dose.
• Some patients report a “refractory” period after taking sildenafil.
• Sildenafil should not be used with certain recreational drugs like poppers.
• The medication’s safety profile is well-understood when used correctly.
• Inform your healthcare provider if you experience prolonged erections.
• Keep an updated record of all medications while using sildenafil.

The mean steady state volume of distribution (Vss) for sildenafil is 105 L, indicating distribution into the tissues.