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Drugs & Medications

sildenafil

SILDENAFIL (ERECTILE DYSFUNCTION)

COMMON BRAND NAME(S): Viagra

GENERIC NAME(S): SILDENAFIL CITRATE

Uses

Sildenafil is used to treat male sexual function problems (impotence or erectile dysfunction-ED). In combination with sexual stimulation, sildenafil works by increasing blood flow to the penis to help a man get and keep an erection.

This drug does not protect against sexually transmitted diseases (such as HIV, hepatitis B, gonorrhea, syphilis). Practice "safe sex" such as using latex condoms. Consult your doctor or pharmacist for more details.

OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

Sildenafil is also available in other brands and strengths for treating high blood pressure in the lungs (pulmonary hypertension). Do not take this medication with any other product that contains sildenafil or other similar medications for erectile dysfunction-ED or pulmonary hypertension (such as tadalafil, vardenafil).

How to use sildenafil

Read the Patient Information Leaflet provided by your pharmacist before you start taking sildenafil and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

To treat erectile dysfunction-ED, take this drug by mouth as directed by your doctor, usually as needed. Take sildenafil at least 30 minutes, but no more than 4 hours, before sexual activity (1 hour before is the most effective). Do not take more than once daily.

A high-fat meal may delay how quickly the drug begins to work.

The dosage is based on your medical condition, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Tell your doctor if your condition does not improve.

Side Effects

Dizziness, headache, flushing, or stomach upset may occur. Vision changes such as increased sensitivity to light, blurred vision, or trouble telling blue and green colors apart may also occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Sexual activity may put extra strain on your heart, especially if you have heart problems. If you have heart problems and experience any of these serious side effects while having sex, stop and get medical help right away: severe dizziness, fainting, chest/jaw/left arm pain, nausea.

Rarely, sudden decreased vision, including permanent blindness, in one or both eyes (NAION) may occur. If this serious problem occurs, stop taking sildenafil and get medical help right away. You have a slightly greater chance of developing NAION if you have heart disease, diabetes, high cholesterol, certain other eye problems ("crowded disk"), high blood pressure, if you are over 50, or if you smoke.

Rarely, a sudden decrease or loss of hearing, sometimes with ringing in the ears and dizziness, may occur. Stop taking sildenafil and get medical help right away if these effects occur.

In the rare event you have a painful or prolonged erection lasting 4 or more hours, stop using this drug and get medical help right away, or permanent problems could occur.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking sildenafil, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: heart problems (such as heart attack or life-threatening irregular heartbeat in the past 6 months, chest pain/angina, heart failure), stroke in the past 6 months, kidney disease, liver disease, high or low blood pressure, a severe loss of body water (dehydration), penis conditions (such as angulation, fibrosis/scarring, Peyronie's disease), history of painful/prolonged erection (priapism), conditions that may increase the risk of priapism (such as sickle cell anemia, leukemia, multiple myeloma), eye problems (such as retinitis pigmentosa, sudden decreased vision, NAION), bleeding disorders, active stomach ulcers.

This drug may make you dizzy or cause vision problems. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Limit alcoholic beverages.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

This brand of the drug is usually not used in women. During pregnancy, sildenafil should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this medication passes into breast milk. Consult your doctor before breast-feeding.

Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

A product that may interact with this drug is: riociguat.

Sildenafil can cause a serious drop in your blood pressure when used with nitrates, which can lead to dizziness, fainting, and rarely heart attack or stroke. Do not use sildenafil with any of the following: certain drugs used to treat chest pain/angina (nitrates such as nitroglycerin, isosorbide), recreational drugs called "poppers" containing amyl or butyl nitrite.

If you are also taking an alpha blocker medication (such as doxazosin, tamsulosin) to treat an enlarged prostate/BPH or high blood pressure, your blood pressure may get too low which can lead to dizziness or fainting. Your doctor may start treatment with a lower dose of sildenafil to minimize your risk of low blood pressure.

Other medications can affect the removal of sildenafil from your body, which may affect how sildenafil works. Examples include azole antifungals (such as itraconazole, ketoconazole), macrolide antibiotics (such as clarithromycin, erythromycin), HIV protease inhibitors (such as ritonavir, saquinavir), hepatitis C virus protease inhibitors (such as boceprevir, telaprevir), rifampin, among others.

Do not take this medication with any other product that contains sildenafil or other similar medications for erectile dysfunction-ED or pulmonary hypertension (such as tadalafil, vardenafil).

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include severe dizziness, fainting, painful/prolonged erection.

Notes

Do not share this medication with others.

Missed Dose

Not applicable.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Information last revised May 2014. Copyright(c) 2014 First Databank, Inc.

Images

REVATIO 20 MG TABLET
REVATIO 20 MG TABLET
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RVT 20, Pfizer
SILDENAFIL 20 MG TABLET
SILDENAFIL 20 MG TABLET
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TEVA, 5517
VIAGRA 25 MG TABLET
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VGR 25, Pfizer
VIAGRA 50 MG TABLET
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VGR 50, Pfizer
VIAGRA 100 MG TABLET
VIAGRA 100 MG TABLET
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VGR 100, Pfizer
REVATIO 20 MG TABLET
REVATIO 20 MG TABLET

Identification

color
white
shape
round
imprint
RVT 20, Pfizer
This medicine is a white, round, film-coated tablet imprinted with "RVT 20" and "Pfizer".
SILDENAFIL 20 MG TABLET
SILDENAFIL 20 MG TABLET

Identification

color
white
shape
round
imprint
TEVA, 5517
This medicine is a white, round, film-coated tablet imprinted with "TEVA" and "5517".
VIAGRA 25 MG TABLET
VIAGRA 25 MG TABLET

Identification

color
blue
shape
No data.
imprint
VGR 25, Pfizer
This medicine is a blue, diamond, film-coated tablet imprinted with "VGR 25" and "Pfizer".
VIAGRA 50 MG TABLET
VIAGRA 50 MG TABLET

Identification

color
blue
shape
No data.
imprint
VGR 50, Pfizer
This medicine is a blue, diamond, film-coated tablet imprinted with "VGR 50" and "Pfizer".
VIAGRA 100 MG TABLET
VIAGRA 100 MG TABLET

Identification

color
blue
shape
No data.
imprint
VGR 100, Pfizer
This medicine is a blue, diamond, film-coated tablet imprinted with "VGR 100" and "Pfizer".

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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