This helps blood flow into your penis more easily, and helps you get firmer erections that last for longer. Headache is the most common, and stuffy nose and facial flushing are quite common too. This lets blood through into the penis, and fills up a stretch of tissue called the corpus cavernosum. Can women take Viagra? They require a prescription for any controlled substance and have a licensed pharmacist to answer questions rather than support staff. The best online pharmacies are accredited by the National Association of Boards of Pharmacy and are licensed in every state in which they trade.Get a Savings Card. Sign up for a Savings Card and, if eligible, you may save 50% on up to 12 prescriptions of brand-name VIAGRA per year.* * Terms and conditions apply. Check . The four main medicines taken by mouth for erectile dysfunction are: Avanafil (Stendra). Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 . Depending on your symptoms and needs, you may be prescribed Viagra, sildenafil, Cialis, tadalafil, Stendra, paroxetine, or a combination of tadalafil and sildenafil, available as .