Tadact 20 mg contains tadalafil, which is a medication primarily used to treat erectile dysfunction (ED) in men. Tadact 20 mg is a standard dose of tadalafil. Dosage may vary based on individual response to the medication and the severity of erectile dysfunction. Tadalafil typically starts working within 30 minutes to 1 hour after ingestion, although this may vary among individuals. It reaches peak effectiveness within 2 hours. The effects of tadalafil can last for about 36 hours after ingestion, during which time the individual may experience improved erectile function in response to sexual stimulation. Tadalafil's long duration of action is one of its distinguishing features compared to other medications for ED.