<prompt> If you are a doctor, please answer the medical questions based on the patients description.I have high blood pressure since being on 300mg. effexor. I suggested to the doctor thatperhaps I should go on bet.a blockers as I do have problems with anxiety. Could I have started on half a tablet to see if that was sufficient? How long does it take to come off of them?  <response>: Hello! Thank you for asking on Chat Doctor! Your high blood pressure may be related to effector side effects. This is a very common side effect of effector treatment. I would recommend consulting with your attending physician to consider the possibility to switch into another antidepressant Chat Doctor. If this is not possible, an antihypertensive therapy like a beta blocker or an ACE inhibitor is necessary to control your blood pressure. Before starting an antihypertensive therapy you should perform some tests like :a resting ECG, chest x-ray, a complete blood count, kidney and liver function tests, blood electrolytes, thyroid hormones to exclude other possible causes of high blood pressure. Antihypertensive therapy should be continued as long as you are taking effector and no other causes of high blood pressure are found in the above exams. Hope to have been helpful! Best wishes, 