While each PDE5 inhibitor differs slightly, they’re very similar in treating erectile dysfunction. You can take it in a small dose daily or in a larger dose as needed. Vardenafil usually works for 4 to 5 hours. Privacy: Confirm that your personal data and payment details are confidential. Cialis tadalafil : This ED medication works with the same principle as Viagra, but lasts up to 36 hours. Oral medicines for ED usually work well and cause few side effects. This boosts blood flow and helps you get an erection from sexual activity.Trick or Treating. Top 10 Best Viagra in New York, NY – November – Yelp – Michael A. Werner, MD, FACS, Hallmark Pharmacy, Neergaard Pharmacies, Duane Reade, Dong . Sildenafil (Viagra). This medicine works best when you take it on an empty stomach an hour before sex. The body takes longer to absorb it after a high-fat meal or Missing: nyc.  · a light-headed feeling, like you might pass out. Common sildenafil side effects may include: flushing (warmth, redness, or tingly feeling); headache, dizziness; Missing: nyc.