Most men aged 18 and over can take sildenafil for erectile dysfunction. Most adults and children aged 1 year and over can take sildenafil for pulmonary hypertension. Who may not be able to take sildenafil Sildenafil is not suitable for some people. To make sure it’s safe .Using alcohol or tobacco with certain medicines may also cause interactions to occur. Store mixed oral liquid in the refrigerator. Place the tip of the syringe into you or your child’s mouth and point it towards the cheek. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco. The effects may be increased because of slower removal of the medicine from the body. Do not press on the plunger of the syringe. However, the dose is usually not more than 80 mg 3 times a day.Common Viagra side effects may include: flushing (warmth, redness, or tingly feeling); headache, dizziness; abnormal vision (blurred vision, changes in color vision) runny or . 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, . Viagra (sildenafil) is a prescription drug that’s used to treat erectile dysfunction (ED). The drug comes as a tablet you’ll take by swallowing. It’s usually taken as needed about 1 .Place the tip of the syringe into you or your child’s mouth and point it towards the cheek. Keep from freezing. Your doctor may adjust your dose if needed. Storage Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. This medicine comes with a patient information leaflet. Do not take other medicines unless they have been discussed with your doctor.