Why isn't Viagra working?
Usually for a reason that can be fixed. Sildenafil does not cause an erection on its own — "Sexual stimulation is still needed" (healthdirect — Sildenafil (Viagra)) — and a heavy meal can delay it (EMA — Viagra product information). The condition behind the erectile dysfunction matters too. If it is not working for you, healthdirect's advice is to "speak to your doctor about changing the dose or treatment option" (healthdirect — Sildenafil (Viagra)). The causes and fixes are in why Viagra may not work, and what helps.
Can you become tolerant to or dependent on Viagra?
In the label's long-term studies, "the safety and efficacy of sildenafil was maintained" (EMA — Viagra product information), and in a four-year study more than 94% of men stayed satisfied (McMurray 2007); one survey reported some men needing a higher dose over time. Whether it is habit-forming is answered in can you become dependent on Viagra? and can you develop a tolerance to Viagra?
Does Viagra cure ED, or cause permanent damage?
It does not cure it: sildenafil "does not: cure erectile dysfunction (ED), increase your sexual desire" (healthdirect — Sildenafil (Viagra)). The one lasting harm the leaflet warns about is an erection that will not go down: after 4 hours it needs urgent medical attention (Viagra CMI). See can Viagra permanently cure ED? and can Viagra cause permanent ED?
Does Viagra make you bigger, or keep you hard after ejaculation?
No to both. It helps an erection happen with arousal; it does not increase size permanently. See does Viagra make you bigger? and can Viagra keep you hard after ejaculation?
Can a healthy man take Viagra?
It is a prescription medicine for erectile dysfunction, and it does not increase sexual desire (healthdirect — Sildenafil (Viagra)). The question is answered in can a healthy person take Viagra?
