Blurry vision, difficulty focusing, depression, high prolactin hormone level. Are these things causing each other?

Possibly. One thought: a pituitary tumor can cause problems with vision, dizziness, mood changes, depression, headaches, v libido, production of breast milk, menstrual changes (to flow ; regularity), ^ blood pressure ; change in weight. A prolactinoma is the most common type of pituitary tumor. It can increase prolactin levels. Some medications can also ^ prolactin levels. Medical evaluation would help to.