Patient Eligibility for Sildenafil 60mg Therapy

**Antacids:**Single doses of an aluminum and magnesium hydroxide-containing antacid did not affect the oral bioavailability of sildenafil. Cimetidine: Plasma sildenafil concentrations increased by approximately 56% in healthy individuals who received a single 50-mg oral dose of the drug concomitantly with a single oral dose of cimetidine (800 mg), a nonspecific inhibitor of the cytochrome P-450 mixed-function oxidase system.

• Sildenafil 60mg may cause headaches as a common side effect.
• Avoid grapefruit or grapefruit juice while on this medication.
• Consult a doctor before combining with other medications.
• Do not use if you have severe heart or liver problems.

[1][67] Population pharmacokinetic analysis of data from clinical trials indicates that cimetidine reduces sildenafil clearance when these drugs are administered concomitantly.

Patient Information for Revatio

**Antacids:**Single doses of an aluminum and magnesium hydroxide-containing antacid did not affect the oral bioavailability of sildenafil. Cimetidine: Plasma sildenafil concentrations increased by approximately 56% in healthy individuals who received a single 50-mg oral dose of the drug concomitantly with a single oral dose of cimetidine (800 mg), a nonspecific inhibitor of the cytochrome P-450 mixed-function oxidase system. [1][67] Population pharmacokinetic analysis of data from clinical trials indicates that cimetidine reduces sildenafil clearance when these drugs are administered concomitantly. [1][139] Some clinicians recommend that a lower initial sildenafil dose (25 mg) be considered in patients with ED receiving cimetidine. Concomitant use of any form of organic nitrate (e.g., nitroglycerin), including recreational use of inhaled nitrites (amyl nitrate or nitrite, ''poppers''), with sildenafil is contraindicated due to the potential pharmacodynamic interaction (increased hypotensive effect).

Special Populations

However, the American College of Cardiology (ACC) and American Heart Association (AHA) recognize that use of organic nitrates and nitrites in patients receiving sildenafil may not be completely avoidable, provided sufficient time has elapsed between use of sildenafil and administration of the nitrate or nitrite. [67] Although it is not known how much time must elapse between use of sildenafil and administration of a nitrate or nitrite, pharmacokinetic data suggest that these latter agents should not be given within 24 hours of sildenafil administration because an exaggerated hypotensive response is likely; plasma sildenafil concentrations are substantially lower 24 hours after a dose than peak concentrations. [1][29][31][67] The point at which nitrates or nitrites can be given safely is unclear, and therefore the drugs should be avoided unless, in the view of the treating clinician, the benefits outweigh the risks. If consideration is given to administering a nitrate or nitrite beyond 24 hours after sildenafil use, the response to the initial doses must be monitored carefully and proper facilities for fluid and vasopressor (e.g., α-adrenergic agonists) support must be readily available to prevent acute ischemic episodes. [67][159] In patients in whom clearance of sildenafil and/or its metabolites may be prolonged (e.g., those with hepatic [e.g., cirrhosis] or severe renal impairment [e.g., creatinine clearance less than 30 mL/minute], those receiving a potent inhibitor of CYP3A4, geriatric patients older than 65 years of age), a more extended period of time between use of sildenafil and administration of a nitrate or nitrite may be necessary. [1][139] Some clinicians recommend that a lower initial sildenafil dose (25 mg) be considered in patients with ED receiving cimetidine. Concomitant use of any form of organic nitrate (e.g., nitroglycerin), including recreational use of inhaled nitrites (amyl nitrate or nitrite, ''poppers''), with sildenafil is contraindicated due to the potential pharmacodynamic interaction (increased hypotensive effect). However, the American College of Cardiology (ACC) and American Heart Association (AHA) recognize that use of organic nitrates and nitrites in patients receiving sildenafil may not be completely avoidable, provided sufficient time has elapsed between use of sildenafil and administration of the nitrate or nitrite.

[67] Although it is not known how much time must elapse between use of sildenafil and administration of a nitrate or nitrite, pharmacokinetic data suggest that these latter agents should not be given within 24 hours of sildenafil administration because an exaggerated hypotensive response is likely; plasma sildenafil concentrations are substantially lower 24 hours after a dose than peak concentrations. [1][29][31][67] The point at which nitrates or nitrites can be given safely is unclear, and therefore the drugs should be avoided unless, in the view of the treating clinician, the benefits outweigh the risks. If consideration is given to administering a nitrate or nitrite beyond 24 hours after sildenafil use, the response to the initial doses must be monitored carefully and proper facilities for fluid and vasopressor (e.g., α-adrenergic agonists) support must be readily available to prevent acute ischemic episodes. [67][159] In patients in whom clearance of sildenafil and/or its metabolites may be prolonged (e.g., those with hepatic [e.g., cirrhosis] or severe renal impairment [e.g., creatinine clearance less than 30 mL/minute], those receiving a potent inhibitor of CYP3A4, geriatric patients older than 65 years of age), a more extended period of time between use of sildenafil and administration of a nitrate or nitrite may be necessary. [1][67][154] In either case, a short-acting nitrate formulation that can be titrated readily (e.g., IV nitroglycerin) is preferred and such use should be accompanied by close hemodynamic monitoring. Sildenafil 50 mg did not potentiate the hypotensive effect of alcohol (0.5 g/kg) in healthy individuals (mean maximum blood alcohol concentrations of 0.08% achieved). Sildenafil has systemic vasodilatory effects and may augment the blood pressure-lowering effect of other antihypertensive agents. [1] Hypotensive responses secondary to sildenafil use in patients receiving antihypertensive therapy have been observed. The risk of an undesired hypotensive response is of particular concern in patients with congestive heart failure and a borderline low blood volume and low blood pressure status as well as in patients with left-ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis), those with severely impaired autonomic control of blood pressure, and in those who are receiving a complex, multidrug antihypertensive regimen. The AUC of the active metabolite, N-desmethyl sildenafil, was increased 62% by loop and potassium-sparing diuretics and 102% by nonspecific β-adrenergic blocking agents; however, the increased active metabolite concentrations are not expected to be clinically important.

Drug Interactions

Other Interactions

Additive hypotensive effects may be anticipated when PDE type 5 inhibitors are administered concurrently with α-adrenergic blocking agents (e.g., terazosin, doxazosin, tamsulosin). [1] Stepwise increases in the dosage of the α-adrenergic blocking agent may further lower blood pressure when a PDE type 5 inhibitor is administered concurrently. [1] In several placebo-controlled crossover studies in patients with benign prostatic hyperplasia receiving doxazosin (4 or 8 mg daily) under steady-state conditions, administration of a single dose of sildenafil (50 or 100 mg) resulted in symptomatic hypotension (e.g., dizziness, lightheadedness, nausea, headache, fatigue) in some patients, occurring within approximately 0.5-4 hours of sildenafil administration.

• The drug belongs to the phosphodiesterase inhibitor class.
• It can cause nasal congestion and dyspepsia.
• It is not intended for recreational use.
• Effectiveness may vary among individuals.

[1] Although symptomatic hypotension occurred in a few patients who received sildenafil 50 or 100 mg, syncope was not reported during these drug interaction studies. [1] Caution sildenafil 50 mg tab is advised when PDE type 5 inhibitors are used concomitantly with an α-adrenergic blocking agent. [1] Patients should be hemodynamically stable on α-adrenergic blocking therapy prior to initiating therapy with a PDE type 5 inhibitor.

[1] Patients who demonstrate hemodynamic instability on α-adrenergic blocking therapy are at increased risk of symptomatic hypotension with concomitant use of PDE type 5 inhibitors.

Comparing Drug Interactions

[1][241] The clinical importance of this pharmacokinetic interaction is unclear. Concomitant administration of sildenafil and heparin in rabbits had an additive effect on bleeding time. [1] Although the possibility of a similar interaction in humans has not been studied specifically to date, there currently is no evidence that would preclude the use of heparin in sildenafil-treated patients if indicated. Pretreatment with erythromycin (500 mg twice daily for 5 days), a specific CYP3A4 inhibitor, increased the AUC of a single 100-mg dose of sildenafil by 182%.

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[1] In patients who are hemodynamically stable on α-adrenergic blocking therapy, PDE type 5 inhibitors should be initiated at the lowest recommended dose. [1] Conversely, in patients taking an optimized dose of a PDE type 5 inhibitor, therapy with an α-adrenergic blocking agent should be initiated at the lowest recommended dosage.

FDA and sildenafil 20mg

Usual Geriatric Dose for:

[1] Incremental increases in the dosage of the α-adrenergic blocking agent during such concomitant therapy may be associated with a further lowering of blood pressure. [1] Safety of combination therapy with an α-adrenergic blocking agent may be affected by other variables, including intravascular volume depletion and concomitant use of other antihypertensive agents.

• Sildenafil 60mg may interact with blood pressure medications.
• Use with caution if you have a history of priapism.
• Blood tests may be required before starting treatment.
• Regular medical check-ups are recommended.

Following administration of a single 100-mg sildenafil dose in hypertensive patients whose blood pressure was controlled with amlodipine 5 or 10 mg daily, mean supine blood pressure was reduced (systolic by 8 mm Hg, diastolic by 7 mm Hg). [1][29][154] The greatest decreases in supine systolic and diastolic blood pressures following sildenafil administration were in patients with the highest baseline blood pressures, suggesting that the likelihood of a hypotensive episode during combined use with amlodipine is low.

• Sildenafil 60mg is used to treat erectile dysfunction.
• It works by relaxing blood vessels to increase blood flow.
• The usual dosing frequency is once a day.
• Do not take more than one dose in 24 hours.

While reported experience with use of sildenafil in HIV-infected patients receiving antiretroviral therapy is limited, clinically important pharmacokinetic interactions have been demonstrated when the drug was used concomitantly with ritonavir and saquinavir. [1][240] Pretreatment with saquinavir (1200-mg liquid-filled capsules [no longer commercially available in the US] 3 times daily) or ritonavir (500 mg twice daily) followed by a single dose of sildenafil (100 mg) increased sildenafil AUC by 210 or 1000%, respectively, and sildenafil peak plasma concentrations by 140 or 300%, respectively.

What side effects can this medication cause?

[1] Caution sildenafil 50 mg tab is advised when PDE type 5 inhibitors are used concomitantly with an α-adrenergic blocking agent. [1] Patients should be hemodynamically stable on α-adrenergic blocking therapy prior to initiating therapy with a PDE type 5 inhibitor. [1] Patients who demonstrate hemodynamic instability on α-adrenergic blocking therapy are at increased risk of symptomatic hypotension with concomitant use of PDE type 5 inhibitors. [1] In patients who are hemodynamically stable on α-adrenergic blocking therapy, PDE type 5 inhibitors should be initiated at the lowest recommended dose. [1] Conversely, in patients taking an optimized dose of a PDE type 5 inhibitor, therapy with an α-adrenergic blocking agent should be initiated at the lowest recommended dosage.

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[1] Incremental increases in the dosage of the α-adrenergic blocking agent during such concomitant therapy may be associated with a further lowering of blood pressure. [1] Safety of combination therapy with an α-adrenergic blocking agent may be affected by other variables, including intravascular volume depletion and concomitant use of other antihypertensive agents. Following administration of a single 100-mg sildenafil dose in hypertensive patients whose blood pressure was controlled with amlodipine 5 or 10 mg daily, mean supine blood pressure was reduced (systolic by 8 mm Hg, diastolic by 7 mm Hg). [1][29][154] The greatest decreases in supine systolic and diastolic blood pressures following sildenafil administration were in patients with the highest baseline blood pressures, suggesting that the likelihood of a hypotensive episode during combined use with amlodipine is low. While reported experience with use of sildenafil in HIV-infected patients receiving antiretroviral therapy is limited, clinically important pharmacokinetic interactions have been demonstrated when the drug was used concomitantly with ritonavir and saquinavir. [1][85][136][137][139] In these patients receiving ritonavir and sildenafil, plasma concentrations at 24 hours were approximately 200 ng/mL compared with 5 ng/mL when sildenafil was given alone. [1][139] Sildenafil is only a weak inhibitor of CYP3A4 and CYP2D6 isoenzymes and single doses of the drug had no effect on steady-state saquinavir or ritonavir pharmacokinetics in healthy adults.

Different sildenafil strengths

[1][240] Pretreatment with saquinavir (1200-mg liquid-filled capsules [no longer commercially available in the US] 3 times daily) or ritonavir (500 mg twice daily) followed by a single dose of sildenafil (100 mg) increased sildenafil AUC by 210 or 1000%, respectively, and sildenafil peak plasma concentrations by 140 or 300%, respectively. [1][85][136][137][139] In these patients receiving ritonavir and sildenafil, plasma concentrations at 24 hours were approximately 200 ng/mL compared with 5 ng/mL when sildenafil was given alone. [1][139] Sildenafil is only a weak inhibitor of CYP3A4 and CYP2D6 isoenzymes and single doses of the drug had no effect on steady-state saquinavir or ritonavir pharmacokinetics in healthy adults. A decrease in sildenafil clearance and a substantial increase in sildenafil concentrations also is expected with protease inhibitors alone or in combination with ritonavir (e.g., amprenavir , atazanavir, fosamprenavir, indinavir, lopinavir, nelfinavir, tipranavir, darunavir). In patients receiving protease inhibitors alone or in combination with ritonavir or the HIV integrase strand transfer inhibitor (INSTI) elvitegravir in combination with cobicistat (CYP3A4 inhibitor), experts recommended that sildenafil dosage not exceed 25 mg every 48 hours for the treatment of ED.

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The nonnucleoside reverse transcriptase inhibitors efavirenz, nevirapine, and etravirine may decrease sildenafil exposure via CY3A4 (and 2C19 for etravirine) induction, and experts state that sildenafil dose titration based upon clinical effect may be required. [1][250] Population pharmacokinetic analysis of data from clinical trials indicates that sildenafil clearance is reduced when the drug is administered concomitantly with CYP3A4 inhibitors such as ketoconazole. Because of the possibility of increased systemic exposure and adverse effects, it is recommended that a lower initial sildenafil dose (25 mg) be considered in patients with ED receiving potent CYP3A4 inhibitors such as ketoconazole or itraconazole. Bosentan, a moderate inducer of CYP3A4, CYP2C9, and possibly CYP2C19, can increase sildenafil clearance and decrease plasma sildenafil concentrations. [1][212][241] In one study in healthy men, concomitant use of bosentan (125 mg twice daily) and sildenafil at a dose not approved for the treatment of erectile dysfunction (80 mg 3 times daily) resulted in a 63% decrease in AUC and a 55% decrease in peak plasma concentrations of sildenafil at steady state; AUC and peak plasma concentrations of bosentan were increased by 50 and 42%, respectively. A decrease in sildenafil clearance and a substantial increase in sildenafil concentrations also is expected with protease inhibitors alone or in combination with ritonavir (e.g., amprenavir , atazanavir, fosamprenavir, indinavir, lopinavir, nelfinavir, tipranavir, darunavir). In patients receiving protease inhibitors alone or in combination with ritonavir or the HIV integrase strand transfer inhibitor (INSTI) elvitegravir in combination with cobicistat (CYP3A4 inhibitor), experts recommended that sildenafil dosage not exceed 25 mg every 48 hours for the treatment of ED. The nonnucleoside reverse transcriptase inhibitors efavirenz, nevirapine, and etravirine may decrease sildenafil exposure via CY3A4 (and 2C19 for etravirine) induction, and experts state that sildenafil dose titration based upon clinical effect may be required. [1][250] Population pharmacokinetic analysis of data from clinical trials indicates that sildenafil clearance is reduced when the drug is administered concomitantly with CYP3A4 inhibitors such as ketoconazole.

Other Comments

[1][67][154] In either case, a short-acting nitrate formulation that can be titrated readily (e.g., IV nitroglycerin) is preferred and such use should be accompanied by close hemodynamic monitoring. Sildenafil 50 mg did not potentiate the hypotensive effect of alcohol (0.5 g/kg) in healthy individuals (mean maximum blood alcohol concentrations of 0.08% achieved). Sildenafil has systemic vasodilatory effects and may augment the blood pressure-lowering effect of other antihypertensive agents. [1] Hypotensive responses secondary to sildenafil use in patients receiving antihypertensive therapy have been observed. The risk of an undesired hypotensive response is of particular concern in patients with congestive heart failure and a borderline low blood volume and low blood pressure status as well as in patients with left-ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis), those with severely impaired autonomic control of blood pressure, and in those who are receiving a complex, multidrug antihypertensive regimen.

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The AUC of the active metabolite, N-desmethyl sildenafil, was increased 62% by loop and potassium-sparing diuretics and 102% by nonspecific β-adrenergic blocking agents; however, the increased active metabolite concentrations are not expected to be clinically important. Additive hypotensive effects may be anticipated when PDE type 5 inhibitors are administered concurrently with α-adrenergic blocking agents (e.g., terazosin, doxazosin, tamsulosin). [1] Stepwise increases in the dosage of the α-adrenergic blocking agent may further lower blood pressure when a PDE type 5 inhibitor is administered concurrently. [1] In several placebo-controlled crossover studies in patients with benign prostatic hyperplasia receiving doxazosin (4 or 8 mg daily) under steady-state conditions, administration of a single dose of sildenafil (50 or 100 mg) resulted in symptomatic hypotension (e.g., dizziness, lightheadedness, nausea, headache, fatigue) in some patients, occurring within approximately 0.5-4 hours of sildenafil administration. [1] Although symptomatic hypotension occurred in a few patients who received sildenafil 50 or 100 mg, syncope was not reported during these drug interaction studies. Because of the possibility of increased systemic exposure and adverse effects, it is recommended that a lower initial sildenafil dose (25 mg) be considered in patients with ED receiving potent CYP3A4 inhibitors such as ketoconazole or itraconazole. Bosentan, a moderate inducer of CYP3A4, CYP2C9, and possibly CYP2C19, can increase sildenafil clearance and decrease plasma sildenafil concentrations. [1][212][241] In one study in healthy men, concomitant use of bosentan (125 mg twice daily) and sildenafil at a dose not approved for the treatment of erectile dysfunction (80 mg 3 times daily) resulted in a 63% decrease in AUC and a 55% decrease in peak plasma concentrations of sildenafil at steady state; AUC and peak plasma concentrations of bosentan were increased by 50 and 42%, respectively. [1][241] The clinical importance of this pharmacokinetic interaction is unclear. Concomitant administration of sildenafil and heparin in rabbits had an additive effect on bleeding time. [1] Although the possibility of a similar interaction in humans has not been studied specifically to date, there currently is no evidence that would preclude the use of heparin in sildenafil-treated patients if indicated. Pretreatment with erythromycin (500 mg twice daily for 5 days), a specific CYP3A4 inhibitor, increased the AUC of a single 100-mg dose of sildenafil by 182%.