Brand Revatio

Sildenafil is used to treat high blood pressure in the lungs (pulmonary arterial hypertension) by blocking a certain enzyme (phosphodiesterase-PDE5) in the body. Sildenafil works by relaxing the blood vessels in the lungs and the rest of the body. Decreasing blood pressure in the lungs allows the heart and lungs to work better and improves your ability to exercise.

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, consult your doctor or pharmacist. To treat high blood pressure in the lungs, take this medication by mouth as directed by your doctor, usually 3 times a day (about 4-6 hours apart) with or without food. Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor instructs you otherwise. Grapefruit can increase the amount of this medication in your bloodstream. Consult your doctor or pharmacist for more details. The dosage is based on your medical condition and response to treatment. Consult your doctor or pharmacist for more details. Use this medication regularly in order to get the most benefit from it. To help you remember, take it at the same times each day. Tell your doctor if your condition does not improve or if it worsens.

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: sickle cell disease, high or low blood pressure, a severe loss of body water (dehydration), history of painful/prolonged erection (priapism), eye problems (such as decreased vision in one or both eyes, retinitis pigmentosa), heart problems (such as heart attack or irregular heartbeat in the past 6 months, heart failure, chest pain/angina, aortic stenosis, idiopathic hypertrophic subaortic stenosis), kidney disease, liver disease, fluid in the lungs (pulmonary edema), problem with shape of penis (such as angulation, fibrosis/scarring, Peyronie's disease), stroke in the past 6 months. 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). 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.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

See also How to Use section. 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. Some products that may interact with this drug include: certain recreational drugs ("poppers") containing amyl/butyl nitrite, alpha blocker medication (such as doxazosin, prazosin, terazosin), bosentan. Other medications can affect the removal of sildenafil from your body, which may affect how sildenafil works. Examples include cimetidine, anticonvulsants (such as carbamazepine, phenobarbital, phenytoin), azole antifungals (such as ketoconazole, itraconazole), macrolide antibiotics (such as erythromycin), rifamycins (such as rifabutin), HIV drugs (such as ritonavir, saquinavir, delavirdine), St. John's wort, among others. Sildenafil may interact with certain chest pain medications (nitrates such as nitroglycerin, isosorbide) causing a dangerous drop in blood pressure. Do not take sildenafil if you also use nitrates. Talk with your doctor or pharmacist for more details and for information on what to do if you get unusual chest pain. Do not take this medication with any other product that contains sildenafil or other similar medications for erection problems/pulmonary hypertension (such as tadalafil, vardenafil).

Dizziness, lightheadedness, headache, flushing, heartburn, nosebleeds, trouble sleeping, or swollen hands/ankles/feet (edema) 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, notify your doctor or pharmacist promptly. To minimize 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. Rarely, a sudden loss of eyesight in one or both eyes (NAION) may occur. This may or may not be due to sildenafil. Get medical help right away if this occurs. You have a slightly greater chance of developing this serious eye problem if you have heart disease, diabetes, high cholesterol, certain other eye problems ("crowded disk"), or high blood pressure, or if you smoke or are over 50. For males, in the unlikely event you have a painful or prolonged erection lasting 4 or more hours, get medical help right away or permanent problems could occur. Rarely, sildenafil may cause sudden hearing problems (such as decrease/loss of hearing in one or both ears, ringing in the ears). Get medical help right away if these effects 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.

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 for more details about how to safely discard your product.