The most common side effect with caverject is pain termed as mild to moderate. Acute pain has also been seen in patients using caverject. When prostaglandins are released naturally in the body, pain is the result therefore it is thought that exogenous prostiglandins sometimes cause pain. Patients suffering from acute pain are not good candidates for the use caverject at this time. Priapism as defined by Upjohn is a painful erection lasting longer than 6 hours.
Priapism is thought to be a dose related response problem.
It should be noted that those patients having painful erections for less than 6 hours were classified as prolonged erections.