If you are taking sildenafil for erectile dysfunction, your doctor will probably start you on an average dose of sildenafil and increase or decrease your dose depending on your response to the medication. The best time to take sildenafil is about 1 hour before sexual activity, but you can take the medication any time from 4 hours to 30 minutes before sexual activity. If you are taking sildenafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule.The best time to take sildenafil is about 1 hour before sexual activity, but you can take the medication any time from 4 hours to 30 minutes before sexual activity.An official website of the United States governmentThis increased blood flow can cause an erection.Call your doctor if you have any unusual problems while you are taking this medication.It is not known if the hearing loss was caused by the medication.Continue to take sildenafil even if you feel well.Share sensitive information only on official, secure websites.If you are taking sildenafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. Some side effects can be serious. If you experience any of the following symptoms, 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. Some patients experienced a sudden decrease or loss of hearing after they took sildenafil or other medications that are similar to sildenafil. If you are taking sildenafil for erectile dysfunction, you are unlikely to miss a dose since this medication is taken as needed, not on a regular dosing schedule. Keep this medication in the container it came in, tightly closed, and out of reach of children.Talk to your pharmacist about take-back programs in your community.If you are taking sildenafil to treat erectile dysfunction, follow your doctor's directions and the guidelines in this paragraph.If you are taking sildenafil for PAH, take the missed dose as soon as you remember it.If you are taking sildenafil for erectile dysfunction, you are unlikely to miss a dose since this medication is taken as needed, not on a regular dosing schedule.However, if you take sildenafil with a high-fat meal, it will take longer for the medication to start to work.If you are taking sildenafil for PAH, you should know that sildenafil controls PAH but does not cure it. What special precautions should I follow? Talk to your pharmacist about take-back programs in your community. Place the medication in a safe location – one that is up and away and out of their sight and reach. Call your doctor if you have any unusual problems while you are taking this medication. Do not take a double dose to make up for a missed one. What special dietary instructions should I follow? Do not take a double dose to make up for a missed one.Sildenafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow easily.Some patients experienced a sudden decrease or loss of hearing after they took sildenafil or other medications that are similar to sildenafil.Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.If you are taking sildenafil (Liqrev, Revatio) for PAH, do not stop taking your medication until you talk to your doctor.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. Sildenafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow easily. This increased blood flow can cause an erection. Share sensitive information only on official, secure websites. An official website of the United States government What side effects can this medication cause? 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 have certain health conditions or are taking certain medications, your doctor may tell you to take sildenafil less often. If you are taking sildenafil to treat erectile dysfunction, follow your doctor's directions and the guidelines in this paragraph. Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. If you have certain health conditions or are taking certain medications, your doctor may tell you to take sildenafil less often.Do not stop taking sildenafil without talking to your doctor.Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.Do not take a double dose to make up for a missed one.Sildenafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow easily. Why is this medication prescribed? Sildenafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow easily.Some patients experienced a sudden decrease or loss of hearing after they took sildenafil or other medications that are similar to sildenafil.Do not take a double dose to make up for a missed one.If you have certain health conditions or are taking certain medications, your doctor may tell you to take sildenafil less often.Do not stop taking sildenafil without talking to your doctor.Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.If you are taking sildenafil (Liqrev, Revatio) for PAH, do not stop taking your medication until you talk to your doctor. Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient. Do not stop taking sildenafil without talking to your doctor. Continue to take sildenafil even if you feel well. If you are taking sildenafil for PAH, you should know that sildenafil controls PAH but does not cure it. Why is this medication prescribed? Bring this list with you each time you visit a doctor or if you are admitted to the hospital.Keep all medication out of sight and reach of children as many containers are not child-resistant.Place the medication in a safe location – one that is up and away and out of their sight and reach.This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. If you are taking sildenafil (Liqrev, Revatio) for PAH, do not stop taking your medication until you talk to your doctor. It is not known if the hearing loss was caused by the medication. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. If you are taking sildenafil for PAH, take the missed dose as soon as you remember it. Tell your doctor if sildenafil is not working well or if you are experiencing side effects. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Sildenafil does not prevent pregnancy or the spread of sexually transmitted diseases such as human immunodeficiency virus (HIV). Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately: Do not mix the liquid with other medications or add anything to flavor the medication. Shake the liquid well for 10 seconds before each use to mix the medication evenly.Use the oral syringe provided with your medication to measure and take your dose. However, if you take sildenafil with a high-fat meal, it will take longer for the medication to start to work. What special dietary instructions should I follow? The best time to take sildenafil is about 1 hour before sexual activity, but you can take the medication any time from 4 hours to 30 minutes before sexual activity.This increased blood flow can cause an erection.If you are taking sildenafil for erectile dysfunction, your doctor will probably start you on an average dose of sildenafil and increase or decrease your dose depending on your response to the medication.Continue to take sildenafil even if you feel well.If you are taking sildenafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire.It is not known if the hearing loss was caused by the medication.Do not mix the liquid with other medications or add anything to flavor the medication.Sildenafil does not prevent pregnancy or the spread of sexually transmitted diseases such as human immunodeficiency virus (HIV). Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. The association of erectile dysfunction with productivity and absenteeism in eight countries globally. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. Ask your pharmacist any questions you have about refilling your prescription. This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information. If you are taking sildenafil to treat PAH, you will probably take sildenafil three times a day with or without food.Take sildenafil at around the same times every day. Take sildenafil as needed before sexual activity. Keep all medication out of sight and reach of children as many containers are not child-resistant. Keep this medication in the container it came in, tightly closed, and out of reach of children.