13 NONCLINICAL TOXICOLOGY
Generic for Viagra® may not be safe for men with some pre-existing conditions or who are taking medications that may interact with the drug.
What should I know about storage and disposal of this medication?
Sildenafil tablets should be used with caution, and only when the anticipated benefits outweigh the risks, in patients with a history of NAION. Patients with a”crowded” optic disc may also be at an increased risk of NAION. (5.3) •Patients should stop sildenafil tablets and seek prompt medical attention in the event of sudden decrease or loss of hearing (5.4) •Caution is advised when sildenafil tablets are co-administered with alpha-blockers or anti-hypertensives. Concomitant use may lead to hypotension (5.5) •Decreased blood pressure, syncope, and prolonged erection may occur at higher sildenafil exposures. In patients taking strong CYP inhibitors, such as ritonavir, sildenafil exposure is increased.
Does sildenafil interact with other medicines (drug interactions)?
Decrease in sildenafil tablets dosage is recommended (2.4,5.6) Most common adverse reactions (≥ 2%) include headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness and rash (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Evaric Pharmaceuticals, Inc. at 1-866-495-1995 or FDA at 1-800-FDA-1088 or •Sildenafil tablets can potentiate the hypotensive effects of nitrates, alpha blockers, and anti-hypertensives ( 4.1, 5.5, 7.1, 7.2, 7.3, 12.2) •With concomitant use of alpha blockers, initiate sildenafil tablets at 25 sildenafil film tablet mg dose (2.3) •CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase sildenafil tablets exposure (2.4, 7.4,12.3) •Ritonavir: Do not exceed a maximum single dose of 25 mg in a 48 hour period ( 2.4, 5.6) •Erythromycin or strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, saquinavir): Consider a starting dose of 25 mg (2.4,7.4) Sildenafil tablets are indicated for the treatment of erectile dysfunction. For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, sildenafil tablets may be taken anywhere from 30 minutes to 4 hours before sexual activity. Sildenafil tablets were shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors such as organic nitrates or organic nitrites in any form is therefore contraindicated [see Contraindications (4.1),Drug Interactions (7.1),and Clinical Pharmacology (12.2)]. If you have (or have ever had) heart problems (such as a heart attack), heart disease, irregular heartbeat, angina, chest pain, narrowing of the aortic valve, heart failure, heart surgery, pulmonary hypertension including pulmonary arterial hypertension, stroke, low blood pressure, high blood pressure, a deformed penis shape (Peyronie’s Disease), priapism (an erection that lasts for more than 4 hours), sickle cell anemia, multiple myeloma, leukemia, retinitis pigmentosa (a rare genetic eye disease), severe vision loss (such as NAION), bleeding problems, stomach ulcers, liver problems or kidney problems (such as kidney dialysis), you may be at higher risk for adverse effects. If you have any of these health conditions, or any other health condition, tell your healthcare provider.
- Sildenafil was originally developed to treat hypertension and angina.
- Its effect lasts approximately 4-6 hours depending on individual factors.
- Side effects may include muscle aches and skin rash in some cases.
- Discuss all medications with your doctor to avoid harmful interactions.
- Do not take sildenafil with fatty foods to ensure quicker action.
Your provider should be aware of all medical conditions, prescription drugs and over-the-counter meds that you are taking. Multiple companies make generic for Viagra®, including Teva Pharmaceuticals and Greenstone, a subsidiary of Pfizer Inc. Take sildenafil (generic for Viagra®) about one hour before sexual activity, as it takes about 30 minutes to an hour to begin working.
| Product | Dosage | Quantity + Bonus | Price | |
|---|---|---|---|---|
| Viagra Generic | 50mg | 60 + 4 Pills | 83.93€ 79.93€ | |
| Viagra Generic | 150mg | 20 Pills | 55.02€ 52.40€ | |
| Viagra Generic | 150mg | 270 + 10 Pills | 326.61€ 311.06€ | |
| Kamagra Soft Tabs | 100mg | 272 + 12 Pills | 593.42€ 565.16€ | |
| Viagra Generic | 50mg | 30 + 4 Pills | 54.26€ 51.68€ | |
| Viagra Generic | 200mg | 270 + 10 Pills | 379.76€ 361.68€ | |
| Kamagra Oral Jelly | 100mg | 30 + 5 Sachets | 136.20€ 129.71€ | |
| Kamagra Polo | 100mg | 84 + 4 Pills | 244.49€ 232.85€ | |
| Kamagra Oral Jelly | 100mg | 220 + 18 Sachets | 662.24€ 630.70€ | |
| Kamagra Soft Tabs | 100mg | 60 + 4 Pills | 180.59€ 171.99€ |
Check out our guide on how to take Viagra® for best results.
1. Indications and Usage for Sildenafil Tablets
Usual Adult Dose for:
If you are currently taking any over-the-counter, recreational or prescription drugs or supplements, tell your healthcare provider. Some medications, like nitroglycerin (nitrates), isosorbide dinitrate, riociguat, ritonavir, itraconazole, ketoconazole, alpha blockers and “poppers”, have well-documented drug interactions with sildenafil and could cause serious side effects.
Further information
Generic for Viagra® may not be safe for men with some pre-existing conditions or who are taking medications that may interact with the drug. If you have (or have ever had) heart problems (such as a heart attack), heart disease, irregular heartbeat, angina, chest pain, narrowing of the aortic valve, heart failure, heart surgery, pulmonary hypertension including pulmonary arterial hypertension, stroke, low blood pressure, high blood pressure, a deformed penis shape (Peyronie’s Disease), priapism (an erection that lasts for more than 4 hours), sickle cell anemia, multiple myeloma, leukemia, retinitis pigmentosa (a rare genetic eye disease), severe vision loss (such as NAION), bleeding problems, stomach ulcers, liver problems or kidney problems (such as kidney dialysis), you may be at higher risk for adverse effects. If you have any of these health conditions, or any other health condition, tell your healthcare provider. Your provider should be aware of all medical conditions, prescription drugs and over-the-counter meds that you are taking. Multiple companies make generic for Viagra®, including Teva Pharmaceuticals and Greenstone, a subsidiary of Pfizer Inc.
Warnings for other groups
Take sildenafil (generic for Viagra®) about one hour before sexual activity, as it takes about 30 minutes to an hour to begin working. Check out our guide on how to take Viagra® for best results. If you are currently taking any over-the-counter, recreational or prescription drugs or supplements, tell your healthcare provider. Some medications, like nitroglycerin (nitrates), isosorbide dinitrate, riociguat, ritonavir, itraconazole, ketoconazole, alpha blockers and “poppers”, have well-documented drug interactions with sildenafil and could cause serious side effects. If you are currently taking a PDE5 inhibitor, like Revatio for pulmonary arterial hypertension, talk to your doctor about adjusting your dosage. If you are currently taking a PDE5 inhibitor, like Revatio for pulmonary arterial hypertension, talk to your doctor about adjusting your dosage. There are also some rare, serious side effects of sildenafil, namely an allergic reaction, loss of vision/hearing, or priapism, an erection lasting for more than four hours. Seek emergency medical attention if you experience any of these serious side effects. Learn more about the common warnings and precautions to consider before taking generic Viagra®. You can get the generic for Viagra® through an online or local pharmacy with a prescription from a licensed medical provider. Generic for Viagra® is not available over-the-counter.
How to take tablets
When sildenafil tablets are co-administered with an alpha-blocker, patients should be stable on alpha-blocker therapy prior to initiating sildenafil tablets treatment and sildenafil tablets should be initiated at 25 mg [see Warnings and Precautions (5.5),Drug Interactions (7.2),and Clinical Pharmacology (12.2)]. Ritonavir The recommended dose for ritonavir-treated patients is 25 mg prior to sexual activity and the recommended maximum dose is 25 mg within a 48 hour period because concomitant administration increased the blood levels of sildenafil by 11-fold [see Warnings and Precautions (5.6),Drug Interactions (7.4),and Clinical Pharmacology (12.3)]. CYP3A4 Inhibitors Consider a starting dose of 25 mg in patients treated with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, or saquinavir) or erythromycin. Clinical data have shown that co-administration with saquinavir or erythromycin increased plasma levels of sildenafil by about 3 fold [see Drug Interactions (7.4)and Clinical Pharmacology (12.3)]. Consider a starting dose of 25 mg in patients > 65 years, patients with hepatic impairment (e.g., cirrhosis), and patients with severe renal impairment (creatinine clearance <30 mL/minute) because administration of sildenafil tablets in these patients resulted in higher plasma levels of sildenafil [see Use in Specific Populations ( 8.5, 8.6, 8.7)and Clinical Pharmacology ( 12.3)].
How should I store sildenafil?
Sildenafil Tablets USP, 25 mg are white colored, round-shaped, biconvex, film coated tablets debossed with 'E' on one side and '113' on the other side. Sildenafil Tablets USP, 50 mg are white colored, round-shaped, biconvex, film coated tablets debossed with 'E' on one side and '114' on the other side. Sildenafil Tablets USP, 100 mg are white colored, round-shaped, biconvex, film coated tablets debossed with 'E' on one side and '115' on the other side. Consistent with its known effects on the nitric oxide/cGMP pathway [see Clinical Pharmacology ( 12.1, 12.2)] ,sildenafil tablets were shown to potentiate the hypotensive effects of nitrates, and its administration to patients who are using nitric oxide donors such as organic nitrates or organic nitrites in any form either regularly and/or intermittently is therefore contraindicated. After patients have taken sildenafil tablets, it is unknown when nitrates, if necessary, can be safely administered. To get genuine generic for Viagra®, ensure that you are seeing a healthcare provider licensed in your state and have your prescription filled by a qualified pharmacy, one that is licensed in your state and has 3rd-party accreditations like LegitScript. Package insert / product label Generic name: sildenafil citrate Dosage form: tablet, film coated Drug classes: Agents for pulmonary hypertension, Impotence medications Warnings and Precautions, Effects on the Eye (5.3) 08/2017 Sildenafil tablet is a phosphodiesterase-5 (PDE5) inhibitor indicated for the treatment of erectile dysfunction (ED) (1) •For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, sildenafil tablets may be taken anywhere from 30 minutes to 4 hours before sexual activity (2.1) •Based on effectiveness and toleration, may increase to a maximum of 100 mg or decrease to 25 mg (2.1) •Maximum recommended dosing frequency is once per day (2.1) Tablets: 25 mg, 50 mg, 100 mg (3) •Administration of sildenafil tablets to patients using nitric oxide donors, such as organic nitrates or organic nitrites in any form.
Drug Label Information
There are also some rare, serious side effects of sildenafil, namely an allergic reaction, loss of vision/hearing, or priapism, an erection lasting for more than four hours. Seek emergency medical attention if you experience any of these serious side effects. Learn more about the common warnings and precautions to consider before taking generic Viagra®. You can get the generic for Viagra® through an online or local pharmacy with a prescription from a licensed medical provider. Generic for Viagra® is not available over-the-counter.
Common side effects of Sildenafil
To get genuine generic for Viagra®, ensure that you are seeing a healthcare provider licensed in your state and have your prescription filled by a qualified pharmacy, one that is licensed in your state and has 3rd-party accreditations like LegitScript. Package insert / product label Generic name: sildenafil citrate Dosage form: tablet, film coated Drug classes: Agents for pulmonary hypertension, Impotence medications Warnings and Precautions, Effects on the Eye (5.3) 08/2017 Sildenafil tablet is a phosphodiesterase-5 (PDE5) inhibitor indicated for the treatment of erectile dysfunction (ED) (1) •For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, sildenafil tablets may be taken anywhere from 30 minutes to 4 hours before sexual activity (2.1) •Based on effectiveness and toleration, may increase to a maximum of 100 mg or decrease to 25 mg (2.1) •Maximum recommended dosing frequency is once per day (2.1) Tablets: 25 mg, 50 mg, 100 mg (3) •Administration of sildenafil tablets to patients using nitric oxide donors, such as organic nitrates or organic nitrites in any form. Sildenafil tablets were shown to potentiate the hypotensive effect of nitrates ( 4.1, 7.1, 12.2) •Known hypersensitivity to sildenafil or any component of tablet (4.2) •Administration with guanylate cyclase (GC) stimulators, such as riociguat (4.3) •Patients should not use sildenafil tablets if sexual activity is inadvisable due to cardiovascular status (5.1) •Patients should seek emergency treatment if an erection lasts >4 hours. Use sildenafil tablets with caution in patients predisposed to priapism (5.2) •Patients should stop sildenafil tablets and seek medical care if a sudden loss of vision occurs in one or both eyes, which could be a sign of non arteritic anterior ischemic optic neuropathy (NAION). Sildenafil tablets were shown to potentiate the hypotensive effect of nitrates ( 4.1, 7.1, 12.2) •Known hypersensitivity to sildenafil or any component of tablet (4.2) •Administration with guanylate cyclase (GC) stimulators, such as riociguat (4.3) •Patients should not use sildenafil tablets if sexual activity is inadvisable due to cardiovascular status (5.1) •Patients should seek emergency treatment if an erection lasts >4 hours. Use sildenafil tablets with caution in patients predisposed to priapism (5.2) •Patients should stop sildenafil tablets and seek medical care if a sudden loss of vision occurs in one or both eyes, which could be a sign of non arteritic anterior ischemic optic neuropathy (NAION).
| Storage Requirement | Temperature Range | Light Exposure | Humidity Control | Notes |
|---|---|---|---|---|
| Room Temperature | 20–25°C (68–77°F) | Keep away from direct sunlight | Keep in a dry place | Keep out of reach of children |
| Avoid Humidity | ≤60% RH | Store in original container | Avoid bathroom storage | Protect from moisture |
| Temperature Fluctuations | Avoid extreme temperatures | - | - | Prevent degradation |
Sildenafil tablets should be used with caution, and only when the anticipated benefits outweigh the risks, in patients with a history of NAION. Patients with a”crowded” optic disc may also be at an increased risk of NAION. (5.3) •Patients should stop sildenafil tablets and seek prompt medical attention in the event of sudden decrease or loss of hearing (5.4) •Caution is advised when sildenafil tablets are co-administered with alpha-blockers or anti-hypertensives. Concomitant use may lead to hypotension (5.5) •Decreased blood pressure, syncope, and prolonged erection may occur at higher sildenafil exposures. In patients taking strong CYP inhibitors, such as ritonavir, sildenafil exposure is increased. Decrease in sildenafil tablets dosage is recommended (2.4,5.6) Most common adverse reactions (≥ 2%) include headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness and rash (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Evaric Pharmaceuticals, Inc.
8.4 Pediatric Use
Although plasma levels of sildenafil at 24 hours post dose are much lower than at peak concentration, it is unknown whether nitrates can be safely co-administered at this time point [see Dosage and Administration (2.3),Drug Interactions (7.1),and Clinical Pharmacology (12.2)]. Sildenafil tablets are contraindicated in patients with a known hypersensitivity to sildenafil, as contained in sildenafil tablets and REVATIO, or any component of the tablet. Therefore, treatments for erectile dysfunction, including sildenafil tablets, should not be generally used in men for whom sexual activity is inadvisable because of their underlying cardiovascular status. Sildenafil tablets have 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)].While this normally would be expected to be of little consequence in most patients, prior to prescribing sildenafil tablets, 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.
Adjusting Your Sildenafil Dosage Over Time
at 1-866-495-1995 or FDA at 1-800-FDA-1088 or •Sildenafil tablets can potentiate the hypotensive effects of nitrates, alpha blockers, and anti-hypertensives ( 4.1, 5.5, 7.1, 7.2, 7.3, 12.2) •With concomitant use of alpha blockers, initiate sildenafil tablets at 25 sildenafil film tablet mg dose (2.3) •CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase sildenafil tablets exposure (2.4, 7.4,12.3) •Ritonavir: Do not exceed a maximum single dose of 25 mg in a 48 hour period ( 2.4, 5.6) •Erythromycin or strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, saquinavir): Consider a starting dose of 25 mg (2.4,7.4) Sildenafil tablets are indicated for the treatment of erectile dysfunction. For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity.
| Country | Prescription Requirement | Over-the-Counter Availability | Regulatory Body |
|---|---|---|---|
| USA | Yes | No | FDA |
| UK | Yes | No | MHRA |
| Canada | Yes | No | Health Canada |
| Australia | Yes | No | TGA |
| India | Yes (in some states) | Some brands available OTC | CDSCO |
However, sildenafil tablets may be taken anywhere from 30 minutes to 4 hours before sexual activity. Sildenafil tablets were shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors such as organic nitrates or organic nitrites in any form is therefore contraindicated [see Contraindications (4.1),Drug Interactions (7.1),and Clinical Pharmacology (12.2)].
| Population Group | Considerations | Recommendations |
|---|---|---|
| Elderly | Altered pharmacokinetics | Start with lower dose |
| Patients with Renal Impairment | Slower clearance, risk of accumulation | Dose reduction or careful use |
| Patients with Liver Disease | Reduced metabolism, higher plasma levels | Dose adjustment or caution |
| Women | Not FDA-approved for female ED | Usually not prescribed |
When sildenafil tablets are co-administered with an alpha-blocker, patients should be stable on alpha-blocker therapy prior to initiating sildenafil tablets treatment and sildenafil tablets should be initiated at 25 mg [see Warnings and Precautions (5.5),Drug Interactions (7.2),and Clinical Pharmacology (12.2)]. Ritonavir The recommended dose for ritonavir-treated patients is 25 mg prior to sexual activity and the recommended maximum dose is 25 mg within a 48 hour period because concomitant administration increased the blood levels of sildenafil by 11-fold [see Warnings and Precautions (5.6),Drug Interactions (7.4),and Clinical Pharmacology (12.3)].
- The medication should be stored at room temperature between 15-30°C (59-86°F).
- Keep the tablets in their original container, tightly closed.
- Protect from light and moisture; avoid storing in bathrooms or near sinks.
- Do not use the medication if the packaging is torn or shows signs of tampering.
- Check the expiration date printed on the bottle or blister pack before use.
- Properly discard any medication that is outdated or no longer needed.
- Do not flush medications down the toilet or pour them into a drain.
- Consult a pharmacist or local waste disposal company for proper disposal methods.
- Many communities have drug take-back programs for safe disposal.
- Keeping old medication increases the risk of accidental ingestion or misuse.
- Safe storage and disposal protect children, pets, and the environment.
CYP3A4 Inhibitors Consider a starting dose of 25 mg in patients treated with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, or saquinavir) or erythromycin. Clinical data have shown that co-administration with saquinavir or erythromycin increased plasma levels of sildenafil by about 3 fold [see Drug Interactions (7.4)and Clinical Pharmacology (12.3)]. Consider a starting dose of 25 mg in patients > 65 years, patients with hepatic impairment (e.g., cirrhosis), and patients with severe renal impairment (creatinine clearance <30 mL/minute) because administration of sildenafil tablets in these patients resulted in higher plasma levels of sildenafil [see Use in Specific Populations ( 8.5, 8.6, 8.7)and Clinical Pharmacology ( 12.3)]. Sildenafil Tablets USP, 25 mg are white colored, round-shaped, biconvex, film coated tablets debossed with 'E' on one side and '113' on the other side. Sildenafil Tablets USP, 50 mg are white colored, round-shaped, biconvex, film coated tablets debossed with 'E' on one side and '114' on the other side. Sildenafil Tablets USP, 100 mg are white colored, round-shaped, biconvex, film coated tablets debossed with 'E' on one side and '115' on the other side. Consistent with its known effects on the nitric oxide/cGMP pathway [see Clinical Pharmacology ( 12.1, 12.2)] ,sildenafil tablets were shown to potentiate the hypotensive effects of nitrates, and its administration to patients who are using nitric oxide donors such as organic nitrates or organic nitrites in any form either regularly and/or intermittently is therefore contraindicated. After patients have taken sildenafil tablets, it is unknown when nitrates, if necessary, can be safely administered. Although plasma levels of sildenafil at 24 hours post dose are much lower than at peak concentration, it is unknown whether nitrates can be safely co-administered at this time point [see Dosage and Administration (2.3),Drug Interactions (7.1),and Clinical Pharmacology (12.2)]. Sildenafil tablets are contraindicated in patients with a known hypersensitivity to sildenafil, as contained in sildenafil tablets and REVATIO, or any component of the tablet. Therefore, treatments for erectile dysfunction, including sildenafil tablets, should not be generally used in men for whom sexual activity is inadvisable because of their underlying cardiovascular status. Sildenafil tablets have 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)].While this normally would be expected to be of little consequence in most patients, prior to prescribing sildenafil tablets, 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.
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