Vidalista 20, which contains tadalafil, typically starts to work within 30 to 60 minutes after ingestion. This time frame allows for the medication to be absorbed into the bloodstream and begin its effect of increasing blood flow to the penis, which helps facilitate an erection in response to sexual stimulation. The medication usually begins to show effects within 30 to 60 minutes, but it can vary depending on individual factors such as metabolism, food intake, and overall health. One of the notable features of tadalafil is its long duration of action. It can remain effective for up to 36 hours.