Rarely reported side effects include: an erection that will not go away priapism. Some people may also have ringing in their ears tinnitus or dizziness. If you are taking sildenafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. In these studies, involving about patients, analyses of patient diaries showed no effect of VIAGRA on rates of attempted intercourse about 2 per week , but there was clear treatment-related improvement in sexual function: per patient weekly success rates averaged 1. Also collected as part of the IIEF was information about other aspects of sexual function, including information on erectile function, orgasm, desire, satisfaction with intercourse, and overall sexual satisfaction. Sildenafil is in a class of medications called phosphodiesterase PDE inhibitors. Effects of VIAGRA on Vision: At single oral doses of mg and mg, transient dose-related impairment of color discrimination was detected using the Farnsworth-Munsell hue test, with peak effects near the time of peak plasma levels.Viagra Connect is the first erectile dysfunction medicine in Ireland to be sold without the need for a prescription, which means you can buy Viagra Connect discreetly in store . 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. Can I buy Viagra Connect online? You can buy a prescription for Viagra Connect from online doctor or pharmacy services, like Superdrug Online Doctor. Ordering Viagra .