Tazzle 20 mg FM contains tadalafil 20 mg, a PDE-5 inhibitor primarily used for erectile dysfunction (ED). It works by increasing blood flow to the penis during sexual stimulation, helping achieve and maintain an erection. It does not increase sexual desire or cause an erection without sexual stimulation. Tadalafil 20 mg is generally an as-needed strength for ED, rather than the usual daily dose. It commonly begins working within 30–60 minutes, and its effects can potentially last up to 36 hours. Follow the dose prescribed by your healthcare professional.