However the dose is usually not more than 40 mg 3 times a day. Though it may seem like Sildenafil is the newbie ED medication on the block, there are no big reasons to prefer the more established Viagra product over generic Sildenafil. To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and site usage information with other information we have about you. When did you first begin noticing sexual problems? Your partner can help you remember something that you missed or forgot during the appointment.AdGet Deals and Low Prices On pharmacy prescriptions At Amazon. We Offer an Extensive Selection Of Everything Else Store At Amazon. Order Today!Services: Pet Supplies, Pharmacy, Medical Care, Anxiety, Hypothyroidism and more. Sildenafil (Viagra) Tadalafil (Adcirca, Cialis) Vardenafil (Levitra, Staxyn) Avanafil (Stendra) All four medications enhance the effects of nitric oxide — a natural .  · Adults 65 years of age and older—25 mg as a single dose no more than once a day, 1 hour before sexual intercourse. Alternatively, the medicine may be taken 30 .