You may have your doctor’s office directly submit the script to your preferred pharmacy, or you can take it with you and use the script to purchase Viagra at a pharmacy or online. Common ones include: Flushing of the skin. Vardenafil usually works for 4 to 5 hours. EPO plans, deductibles, etc. An inherited eye disease that affects the retina.You can ask for recommendations from: your PCP other healthcare providers trusted friends or family members You should also check a doctor’s credentials on your state medical . After discussing your erectile dysfunction and your medical history, ask your doctor for a prescription for Viagra. You may have your doctor’s office directly submit the script to . Viagra is meant to be used as a long-term treatment. If you and your doctor determine that Viagra is safe and effective for you, you’ll likely take it long term. Frequently asked .