All medications must be declared upon arrival at the border. Ask your pharmacist for a list of the ingredients. However, if you have medications that are considered a controlled substance including some cough medicines, tranquilizers, sleeping pills, antidepressants, or stimulants, you may only bring up to 50 dosage units across the border without a prescription. The best time to take sildenafil is about 1 hour before sexual activity, but you can take the medication any time from 4 hours to 30 minutes before sexual activity. Summary There are limits to bringing prescriptions purchased at a Mexican pharmacy into the United States. You are encouraged to report adverse events related to Viatris products by calling U.Typical dosing for Sildenafil (Viagra) The typical dose is to take 50 mg of sildenafil (Viagra) by mouth, about 1 hour before sex, as needed. The maximum recommended dose is mg. Don’t take sildenafil (Viagra) more than once daily (at any dose). Written by Brian Leonard, PharmD, BCACP, BCGP. 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. Almost the same with Viagra. So, yes it is available without any script, but the prices do not match up with Chicago and going the normal way of getting the stuff. Now, if you have to .