Tadarise Generic Tadalafil are used to treat erectile dysfunction (impotence) in men. Tadarise Tablets Contain tadalafil, a phosphodiesterase type 5 inhibitor, that is used to treat erectile dysfunction and Impotence in men. The most commonly reported side effects taking into consideration taking Tadarise tablets 20mg improve headache, dizziness or light-headedness, flushing, nasal congestion, dyspepsia (heartburn), nausea.