Does Viagra Connect work instantly? Those with pre-existing conditions should always consult a healthcare provider before taking new medications or supplements. Answer: Viagra is generally thought to be low risk. Can you buy Viagra over the counter? It’s available in 25 mg, 50 mg, and mg tablets and lasts up to 18 hours.Viagra Connect is an over-the-counter pill made by Pfizer that contains sildenafil, the active drug in prescription Viagra Credit: PA:Press Association. In recent years this has . Sildenafil The original ED medication. Our average rating based on reviews. Express shipping US clinicians Starting from $ Get your treatment We’ll deliver to . Compare prices and print coupons for Sildenafil (Generic Revatio and Viagra) and other drugs at CVS, Walgreens, and other pharmacies. Prices start at $