Cialis is a latest medicine for treatment of disturbances of erection at men. Sialis's feature is its high-speed performance (30 minutes) and a long-term effect (up to 36 hours). In this regard you can choose the moment which is most suitable for sexual intercourse, having accepted a drug in advance. It is possible to take Sialis in the morning and to be ready even next day. Active ingredient - Tadalafil, the recommended dosage - 20 mg.