However, others work on a cash-pay basis and don’t partner with insurance companies. Now, the Drug Enforcement Agency DEA has proposed new rules that will require an in-person visit for anything more than a day supply of controlled substances to be filled by an online pharmacy. 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. However, if your Viagra is not covered by insurance, taking the script with you gives you the time to shop for the best price. Knowing whether or not you have insurance to cover the medication will make a difference in how you obtain it. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. A newer form of the medicine that dissolves on the tongue might work faster than the pill that you swallow.Drug Images What is Viagra? Viagra is a brand-name prescription drug that’s approved to treat erectile dysfunction (ED). With ED, you’re unable to have or maintain an erection. . Last updated: June 14, If you’re looking for a less costly Viagra, you might want to ask your doctor about sildenafil. It’s the active ingredient in both branded Viagra and the drug. Viagra is an effective option for ED. Generally, you should take Viagra about 1 hour before engaging in sexual activity. Viagra can start working in as little as 30 minutes, but it can .