McIntosh recommends using a backup form of birth control during those weeks, such as condoms or a vaginal diaphragm, to avoid pregnancy
In studies looking at adverse effects associated with sildenafil, the following were the most common:2 Flushing (reddening of the skin and face) Headache Nasal congestion Heartburn Dyspepsia (stomach discomfort) Visual impairments, including problems with color perception That last effect visual disturbances comes from the fact that sildenafil also weakly inhibits PDE6, which is associated with certain visual processing pathways.46 Men who experience this side effect typically switch to tadalafil or vardenafil with success.9 To learn more, please visit our comprehensive guide to BlueChew side effects
Nature Genetics, Volume 10, Issue 1, May 1995, Pages 111-113 Marvin Boris, M.D
Similarly, while relevant basic research evidence exists, large-scale, multicenter clinical studies are lacking to validate its long-term efficacy