
Do not take more or less of it, or take it more often than prescribed by your doctor. If you are taking sildenafil for erectile dysfunction, your doctor will probably start you on 50 mg of sildenafil and increase or decrease your dose depending on your response to the medication. Tell your doctor if sildenafil is not working well or if you are experiencing side effects.12 If you are taking sildenafil to treat erectile dysfunction, follow your doctor's directions. Tell your doctor if sildenafil is not working well or if you are experiencing side effects.12 Sildenafil tablets for erectile dysfunction come in different strengths ranging from 20 mg to 100 mg. The usual dose is 50 mg, taken once per day when you need it. The dose can be increased to 100 mg or decreased to 25 mg depending on its effect.13 Sildenafil is prescribed off-label for premature ejaculation but has been found effective in 50 mg dosages.14 Work with your healthcare provider to find the right dosage for you. Sildenafil tablets for erectile dysfunction come in different strengths ranging from 20 mg to 100 mg.
| Preference | Percentage (%) | Notes |
|---|---|---|
| Generic over Brand | 65 | Cost-saving option |
| Purchase Online | 70 | Convenience and lower price |
| Brand-name preference | 30 | Trust and efficacy |
| Bulk Buying | 25 | Cost efficiency |
Without insurance, sildenafil can cost as much as $15 per tablet.15 RedBox Rx offers sildenafil for as low as $1 per tablet. Sildenafil requires a doctor’s prescription and is not available over the counter.16 Start an online consult for erectile dysfunction or premature ejaculation with RedBox Rx to find fast, affordable and discreet support.
Do not take any more doses of sildenafil or similar medications such as tadalafil (Cialis) or vardenafil (Levitra) until you talk to your doctor. There have been reports of heart attack, stroke, irregular heartbeat, bleeding in the brain or lungs, high blood pressure and sudden death in men who took sildenafil for erectile dysfunction. Most, but not all, of these people had heart problems before taking sildenafil. It is not known whether these events were caused by sildenafil, sexual activity, heart disease or a combination of these and other causes. Talk to your doctor about the risks of taking sildenafil.
Some patients experienced a sudden decrease or loss of hearing after they took sildenafil or other medications that are similar to sildenafil. The hearing loss usually involved only one ear and did not always improve when the medication was stopped. It is not known if the hearing loss was caused by the medication. If you experience a sudden loss of hearing, sometimes with ringing in the ears or dizziness, while you are taking sildenafil, call your doctor immediately. If you are taking sildenafil (Viagra®) for erectile dysfunction, do not take any more doses of sildenafil (Viagra®) or similar medications such as tadalafil (Cialis®) or vardenafil (Levitra®) until you talk to your doctor. Sildenafil is not FDA-approved for women but may be prescribed in certain situations.17 Sildenafil is not FDA-approved for women but may be prescribed in certain situations.17 PDE5 inhibitors such as sildenafil, tadalafil, avanafil and vardenafil all work in the same basic way by relaxing blood vessels to increase blood flow to the penis. They are all effective for treating erectile dysfunction, but they differ mainly in how quickly they start working and how long their effects last.18Read our Complete Guide to Compare ED Medications to learn more. PDE5 inhibitors such as sildenafil, tadalafil, avanafil and vardenafil all work in the same basic way by relaxing blood vessels to increase blood flow to the penis. It typically has a shelf life of about two years, but check your medication’s bottle for a more specific date.19 It typically has a shelf life of about two years, but check your medication’s bottle for a more specific date.19 Before taking sildenafil: Tell your doctor and pharmacist if you are allergic to sildenafil, any other medications or any of the ingredients in sildenafil products. Ask your pharmacist for a list of the ingredients.
| Product | Dosage | Quantity + Bonus | Price | |
|---|---|---|---|---|
| Viagra Generic | 50mg | 120 + 6 Pills | 129.64€ 123.47€ | |
| Viagra Generic | 50mg | 30 + 4 Pills | 54.26€ 51.68€ | |
| Kamagra | 100mg | 84 + 6 Pills | 264.44€ 251.85€ | |
| Kamagra Polo | 100mg | 84 + 4 Pills | 244.49€ 232.85€ | |
| Viagra Generic | 150mg | 20 Pills | 55.02€ 52.40€ | |
| Viagra Generic | 50mg | 180 + 8 Pills | 158.82€ 151.26€ | |
| Viagra Generic | 25mg | 90 + 6 Pills | 105.03€ 100.03€ | |
| Kamagra Oral Jelly | 100mg | 220 + 18 Sachets | 662.24€ 630.70€ | |
| Viagra Generic | 150mg | 90 + 6 Pills | 147.18€ 140.17€ | |
| Kamagra | 100mg | 60 + 4 Pills | 201.34€ 191.75€ | |
| Kamagra Oral Jelly | 100mg | 30 + 5 Sachets | 136.20€ 129.71€ | |
| Kamagra Polo | 100mg | 120 + 6 Pills | 327.15€ 311.57€ | |
| Kamagra Oral Jelly | 100mg | 21 Sachets | 95.92€ 91.35€ | |
| Viagra Generic | 25mg | 270 + 8 Pills | 184.26€ 175.49€ | |
| Viagra Generic | 100mg | 20 Pills | 45.58€ 43.41€ | |
| Viagra Generic | 25mg | 60 + 4 Pills | 71.99€ 68.56€ | |
| Kamagra | 100mg | 32 Pills | 121.24€ 115.47€ |
Do not take sildenafil if you are taking or have recently taken riociguat (Adempas) or nitrates (medications for chest pain) such as isosorbide dinitrate (Isordil), isosorbide mononitrate (Monoket) and nitroglycerin (Minitran, Nitro-Dur, Nitromist, Nitrostat, others). Nitrates come as tablets, sublingual (under the tongue) tablets, sprays, patches, pastes and ointments. Ask your doctor if you are not sure whether any of your medications contain nitrates.
Do not take street drugs containing nitrates such as amyl nitrate and butyl nitrate (“poppers”) while taking sildenafil. Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins and nutritional supplements you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with sildenafil, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Tell your doctor what herbal products you are taking or plan to take, especially St. John's wort. Tell your doctor if you smoke, if you have ever had an erection that lasted for several hours and if you have recently lost a large amount of body fluids (dehydration). This can happen if you are sick with fever, diarrhea or vomiting; sweat a lot; or do not drink enough liquids. Also tell your doctor if you have or have ever had pulmonary veno-occlusive disease (PVOD; blockage of veins in the sildenafil citrate 100 mg lungs); a stomach ulcer; heart, kidney or liver disease; a heart attack; an irregular heartbeat; a stroke; chest pain; high or low blood pressure; high cholesterol; a bleeding disorder; blood circulation problems; blood cell problems such as sickle cell anemia (a disease of the red blood cells), multiple myeloma (cancer of the plasma cells) or leukemia (cancer of the white blood cells); conditions affecting the shape of the penis (e.g., angulation, cavernosal fibrosis, or Peyronie's disease); or diabetes. Also tell your doctor if you or any of your family members have or have ever had an eye disease such as retinitis pigmentosa (an inherited eye condition that causes loss of vision) or if you have ever had sudden severe vision loss, especially if you were told that the vision loss was caused by a blockage of blood flow to the nerves that help you see.
Tell your doctor if you have ever been advised by a healthcare professional to avoid sexual activity for medical reasons or if you have ever experienced chest pain during sexual activity. Sexual activity may be a strain on your heart, especially if you have heart disease.
They are all effective for treating erectile dysfunction, but they differ mainly in how quickly they start working and how long their effects last.18Read our Complete Guide to Compare ED Medications to learn more. PDE5 inhibitors such as sildenafil, tadalafil, avanafil and vardenafil all work in the same basic way by relaxing blood vessels to increase blood flow to the penis. It typically has a shelf life of about two years, but check your medication’s bottle for a more specific date.19 It typically has a shelf life of about two years, but check your medication’s bottle for a more specific date.19 Before taking sildenafil: Tell your doctor and pharmacist if you are allergic to sildenafil, any other medications or any of the ingredients in sildenafil products. Ask your pharmacist for a list of the ingredients. Do not take sildenafil if you are taking or have recently taken riociguat (Adempas) or nitrates (medications for chest pain) such as isosorbide dinitrate (Isordil), isosorbide mononitrate (Monoket) and nitroglycerin (Minitran, Nitro-Dur, Nitromist, Nitrostat, others).
Nitrates come as tablets, sublingual (under the tongue) tablets, sprays, patches, pastes and ointments. Ask your doctor if you are not sure whether any of your medications contain nitrates. Do not take street drugs containing nitrates such as amyl nitrate and butyl nitrate (“poppers”) while taking sildenafil. Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins and nutritional supplements you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. If you experience chest pain, dizziness or nausea during sexual activity, call your doctor immediately and avoid sexual activity until your doctor tells you otherwise. After you are prescribed, tell all your healthcare providers that you are taking sildenafil. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took sildenafil.20 Tell your doctor and pharmacist if you are allergic to sildenafil, any other medications or any of the ingredients in sildenafil products.
Call your doctor if you have any unusual problems while you are taking this medication. If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).23 Tell your doctor if any of these symptoms are severe or do not go away: Numbness, burning or tingling in the arms, hands, feet or legs Numbness, burning or tingling in the arms, hands, feet or legs Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green) Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green) If you experience any of the following symptoms, call your doctor immediately: Sudden severe loss of vision (see below for more information) Sudden severe loss of vision (see below for more information) Erection that is painful or lasts longer than four hours Erection that is painful or lasts longer than four hours Some patients experienced a sudden loss of some or all their vision after they took sildenafil or other medications that are similar to sildenafil.
Tell your doctor and pharmacist if you are allergic to sildenafil, any other medications or any of the ingredients in sildenafil products. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took sildenafil.20 Grapefruit juice and products may interact with sildenafil, leading to unwanted side effects.
Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.21 Grapefruit juice and products may interact with sildenafil, leading to unwanted side effects.
Do not take more or less of it, or take it more often than prescribed by your doctor. If you are taking sildenafil for erectile dysfunction, your doctor will probably start you on 50 mg of sildenafil and increase or decrease your dose depending on your response to the medication. Tell your doctor if sildenafil is not working well or if you are experiencing side effects.12 If you are taking sildenafil to treat erectile dysfunction, follow your doctor's directions. Tell your doctor if sildenafil is not working well or if you are experiencing side effects.12 Sildenafil tablets for erectile dysfunction come in different strengths ranging from 20 mg to 100 mg. The usual dose is 50 mg, taken once per day when you need it.
The dose can be increased to 100 mg or decreased to 25 mg depending on its effect.13 Sildenafil is prescribed off-label for premature ejaculation but has been found effective in 50 mg dosages.14 Work with your healthcare provider to find the right dosage for you. Sildenafil tablets for erectile dysfunction come in different strengths ranging from 20 mg to 100 mg. Without insurance, sildenafil can cost as much as $15 per tablet.15 RedBox Rx offers sildenafil for as low as $1 per tablet. Sildenafil requires a doctor’s prescription and is not available over the counter.16 Start an online consult for erectile dysfunction or premature ejaculation with RedBox Rx to find fast, affordable and discreet support. Sildenafil is not FDA-approved for women but may be prescribed in certain situations.17 Sildenafil is not FDA-approved for women but may be prescribed in certain situations.17 PDE5 inhibitors such as sildenafil, tadalafil, avanafil and vardenafil all work in the same basic way by relaxing blood vessels to increase blood flow to the penis. Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.21 Sildenafil for erectile dysfunction is taken as needed, not on a regular dosing schedule, so you are unlikely to miss a dose.22 Sildenafil for erectile dysfunction is taken as needed, not on a regular dosing schedule, so you are unlikely to miss a dose.22 Tell your doctor if any of these symptoms are severe or do not go away: Headache Heartburn Diarrhea Flushing (feeling of warmth) Nosebleeds Difficulty falling asleep or staying asleep Numbness, burning or tingling in the arms, hands, feet or legs Muscle aches Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green) Sensitivity to light Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately: Sudden severe loss of vision (see below for more information) Blurred vision Sudden decrease or loss of hearing Ringing in ears Dizziness or lightheadedness Fainting Chest pain Worsening shortness of breath Erection that is painful or lasts longer than four hours Itching or burning during urination Rash Some patients experienced a sudden loss of some or all their vision after they took sildenafil or other medications that are similar to sildenafil.
Many other medications may also interact with sildenafil, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Tell your doctor what herbal products you are taking or plan to take, especially St. John's wort. Tell your doctor if you smoke, if you have ever had an erection that lasted for several hours and if you have recently lost a large amount of body fluids (dehydration). This can happen if you are sick with fever, diarrhea or vomiting; sweat a lot; or do not drink enough liquids.
Also tell your doctor if you have or have ever had pulmonary veno-occlusive disease (PVOD; blockage of veins in the sildenafil citrate 100 mg lungs); a stomach ulcer; heart, kidney or liver disease; a heart attack; an irregular heartbeat; a stroke; chest pain; high or low blood pressure; high cholesterol; a bleeding disorder; blood circulation problems; blood cell problems such as sickle cell anemia (a disease of the red blood cells), multiple myeloma (cancer of the plasma cells) or leukemia (cancer of the white blood cells); conditions affecting the shape of the penis (e.g., angulation, cavernosal fibrosis, or Peyronie's disease); or diabetes. Also tell your doctor if you or any of your family members have or have ever had an eye disease such as retinitis pigmentosa (an inherited eye condition that causes loss of vision) or if you have ever had sudden severe vision loss, especially if you were told that the vision loss was caused by a blockage of blood flow to the nerves that help you see. Tell your doctor if you have ever been advised by a healthcare professional to avoid sexual activity for medical reasons or if you have ever experienced chest pain during sexual activity. Sexual activity may be a strain on your heart, especially if you have heart disease. If you experience chest pain, dizziness or nausea during sexual activity, call your doctor immediately and avoid sexual activity until your doctor tells you otherwise. The vision loss was permanent in some cases. It is not known if the vision loss was caused by the medication.
| Store Type | Average Price (USD) | Delivery Time | Additional Fees |
|---|---|---|---|
| Online Pharmacy A | $8 | 2-3 days | Shipping $2 |
| Local Pharmacy B | $12 | Same day | No extra fee |
| Online Pharmacy C | $7 | 5-7 days | Shipping $3 |
| Local Pharmacy D | $13 | Same day | Prescription required |
If you experience a sudden loss of vision while you are taking sildenafil, call your doctor immediately. Do not take any more doses of sildenafil or similar medications such as tadalafil (Cialis) or vardenafil (Levitra) until you talk to your doctor.
After you are prescribed, tell all your healthcare providers that you are taking sildenafil. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took sildenafil.20 Tell your doctor and pharmacist if you are allergic to sildenafil, any other medications or any of the ingredients in sildenafil products. Tell your doctor and pharmacist if you are allergic to sildenafil, any other medications or any of the ingredients in sildenafil products. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took sildenafil.20 Grapefruit juice and products may interact with sildenafil, leading to unwanted side effects. Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.21 Grapefruit juice and products may interact with sildenafil, leading to unwanted side effects.
Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.21 Sildenafil for erectile dysfunction is taken as needed, not on a regular dosing schedule, so you are unlikely to miss a dose.22 Sildenafil for erectile dysfunction is taken as needed, not on a regular dosing schedule, so you are unlikely to miss a dose.22 Tell your doctor if any of these symptoms are severe or do not go away: Headache Heartburn Diarrhea Flushing (feeling of warmth) Nosebleeds Difficulty falling asleep or staying asleep Numbness, burning or tingling in the arms, hands, feet or legs Muscle aches Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green) Sensitivity to light Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately: Sudden severe loss of vision (see below for more information) Blurred vision Sudden decrease or loss of hearing Ringing in ears Dizziness or lightheadedness Fainting Chest pain Worsening shortness of breath Erection that is painful or lasts longer than four hours Itching or burning during urination Rash Some patients experienced a sudden loss of some or all their vision after they took sildenafil or other medications that are similar to sildenafil. The vision loss was permanent in some cases. It is not known if the vision loss was caused by the medication. If you experience a sudden loss of vision while you are taking sildenafil, call your doctor immediately. There have been reports of heart attack, stroke, irregular heartbeat, bleeding in the brain or lungs, high blood pressure and sudden death in men who took sildenafil for erectile dysfunction. Most, but not all, of these people had heart problems before taking sildenafil. It is not known whether these events were caused by sildenafil, sexual activity, heart disease or a combination of these and other causes. Talk to your doctor about the risks of taking sildenafil. Some patients experienced a sudden decrease or loss of hearing after they took sildenafil or other medications that are similar to sildenafil. The hearing loss usually involved only one ear and did not always improve when the medication was stopped. It is not known if the hearing loss was caused by the medication. If you experience a sudden loss of hearing, sometimes with ringing in the ears or dizziness, while you are taking sildenafil, call your doctor immediately. If you are taking sildenafil (Viagra®) for erectile dysfunction, do not take any more doses of sildenafil (Viagra®) or similar medications such as tadalafil (Cialis®) or vardenafil (Levitra®) until you talk to your doctor. Call your doctor if you have any unusual problems while you are taking this medication. If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).23 Tell your doctor if any of these symptoms are severe or do not go away: Numbness, burning or tingling in the arms, hands, feet or legs Numbness, burning or tingling in the arms, hands, feet or legs Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green) Changes in color vision (seeing a blue tinge on objects or having difficulty telling the difference between blue and green) If you experience any of the following symptoms, call your doctor immediately: Sudden severe loss of vision (see below for more information) Sudden severe loss of vision (see below for more information) Erection that is painful or lasts longer than four hours Erection that is painful or lasts longer than four hours Some patients experienced a sudden loss of some or all their vision after they took sildenafil or other medications that are similar to sildenafil.