One common cause of hyperprolactinemia is a growth or tumor on the pituitary gland called a prolactinoma. The tumor produces high levels of prolactin. These tumors can be large or small and are usually benign, meaning they are not cancerous. Large tumors can also cause headaches, vision problems, or both.
The most common symptoms of atypical antidepressant withdrawal, including Cymbalta, are anxiety and low mood, such as apathy and rebound depression. Because Cymbalta strongly affects serotonin, after discontinuation it can take several days for the body's own serotonin system to return to normal.
Cymbalta may cause sexual side effects in some users. Decreased libido, or sexual desire, may occur in patients who use Cymbalta, specifically in male patients. According to eMedtv.com, about 6 percent of men and 1 percent of women being treated for depression may experience a decreased libido.