Megalis 10 mg is a medication that contains tadalafil as its active ingredient. Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor, similar to sildenafil (found in Viagra) and vardenafil (found in Levitra). Megalis is primarily used for the treatment of erectile dysfunction (ED) in men. Megalis 10 mg indicates the strength or dosage of tadalafil in each tablet. The appropriate dosage may vary from person to person, and your healthcare provider will determine the most suitable dose for you. Tadalafil is the active ingredient in Megalis 10 mg. It works by relaxing the smooth muscles in the blood vessels of the penis, allowing for increased blood flow. This helps men achieve and maintain an erection during sexual stimulation.