Tadagra Prof 20 mg is one of the available dosages of tadalafil. The typical starting dose of tadalafil for treating ED is 10 mg, and Tadagra Prof 20 mg contains a higher dose. Dosage can be adjusted based on individual response and tolerability. The medication is usually taken orally about 30 minutes to an hour before sexual activity and can remain effective for up to 36 hours.