tadalafil, the active component of Tadora , is also available in generic form as a substitute for Cialis. The majority of patients using this medicine are adult males with erectile dysfunction. Erection dysfunction is the inability of a man to achieve or sustain an erection during sexual activity. One drug that aids with erections is tadalafil. Tadora is available in yellow, oval-shaped, film-coated pills that are 12 millimeters long by 8 millimeters wide and divided into equal pieces. This medication functions by increasing the lungs' PDE-5 enzyme levels, which relaxes and enlarges the blood vessels there.