Try having sex without alcohol to see if that solves the problem. Get stimulated and the pills can take it from there. It can be dangerous to take sildenafil if you also take medicines called nitrates often given for chest pain. Brand names Why is this medication prescribed? This can happen if you are sick with fever, diarrhea, or vomiting; sweat a lot; or do not drink enough liquids. How and when to take sildenafil It’s important to take sildenafil as advised by a doctor or pharmacist. Please expect up to 4 to 6 weeks for reimbursement.Accessed 04/18/ 18, Overview Hims is an online telehealth platform for men that provides care for mental health, sexual health, hair loss, skincare and more. Outside of offering.  · Viagra is usually taken only when needed, 30 minutes to 1 hour before sexual activity. You may take it up to 4 hours before sexual activity. Do not take Viagra more than once per day. Shake the oral suspension (liquid) before you measure a dose. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon). According to price-comparison site test1.ru, generic Revatio will cost you as little as $ per pill, depending on where you fill your prescription. That’s compared with more than $50 per.