Medicines that block an enzyme called CYP3A4. Children, and patients with heart disease can also share in this inspiring development. Sildenafil was found to have a beneficial side-effect of curing cardiovascular disease and is normally prescribed to patients with heart disease. You can take this medicine with or without food 30 minutes before sex, depending on the dose. When oral medications might not be safe Check with your health care team before you take any medicine for erectile dysfunction. These include a heart attack, stroke or a serious heart rhythm disorder in the past six months.1. Re: Pharmacies in Bangkok. Pharmacies are all over the place. You find them in many malls, you find them in areas popular with tourists. You find them in some supermarkets too. Boots, Watsons, P&F, Fascino and Siam Pharmacies are some I can think of right now. But there are many smaller private drug stores everywhere. 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. Most popular Low price Walmart $ retail Save 99% $ One-time offer Get free savings Walgreens $1, retail Save 99%.