The generic name for tadalafil 40 mg is Vidalista 40mg. It is used to treat male impotence. It is widely available in a variety of capacities on the market. Vidalista 40 is the tadalafil medication with the highest concentration. If Vidalista(tadalafil) can create an erection that lasts up to 36 hours, it is considered typical. It also works quickly, causing an erection in as little as an hour.