As with any medication, Tadora 20 mg may cause side effects such as headache, indigestion, back pain, muscle aches, flushing, stuffy or runny nose, and dizziness. Serious side effects such as sudden vision loss, hearing loss, and priapism (a prolonged erection lasting more than four hours) are rare but possible. https://www.genericday.com/tadora-20-mg.html