There may be some side effects when taking CIALIS. The most common side effects with CIALIS are: headache, indigestion, back pain, muscle aches, flushing, and stuffy or runny nose. These side effects usually go away after a few hours. Men who get back pain and muscle aches usually get them 12 to 24 hours after taking CIALIS. Back pain and muscle aches usually go away within 2 days.
Uncommon but serious side effects include: An erection that won't go away. If you get an erection that lasts more than 4 hours, seek immediate medical help to avoid long-term injury In rare instances, men taking prescription ED tablets, including CIALIS, reported a sudden decrease or loss of vision or hearing (sometimes with ringing in the ears and dizziness). It's not possible to determine if these events are related directly to the ED tablets or to other factors. If you have a sudden decrease or loss of vision or hearing, stop taking any ED tablet, including CIALIS, and call a healthcare provider right away
These are not all the possible side effects of CIALIS.
Call your healthcare provider if you experience any side effects that bother you or don't go away. And please see Important Safety Information and full Patient Information for additional information.