Bariatric surgery programs often ask for a pre-operative mental health evaluation. The main purpose is to identify any barriers to success after surgery, especially barriers that can be effectively addressed or overcome. We do know that people with some specific mental health conditions such as an active eating disorder, active drug or alcohol problems, severe mood symptoms, or psychotic symptoms – can be barriers to recovery from surgery and losing weight. In these situations, delaying surgery and getting effective treatment can increase the chances of success. Another purpose of a pre-operative mental health evaluation is to understand the psychological factors that may interfere with success, such as using food as a coping mechanism. Counseling focused on these issues can increase the chance of successful weight loss after surgery. It is important to emphasize that having a diagnosis of depression or bipolar disorder does not mean that bariatric surgery is not safe or effective. Research shows that people with depression are just as successful losing weight after surgery. And losing weight often leads to improvement in depression.
While bariatric surgery is more and more common, we lack good research about how surgery affects the dosing, effectiveness, or side effects of mental health medications. Bariatric surgery can certainly change or reduce absorption of medications – so they are less effective. This may be a bigger problem with sustained- or slow-release medications. With some medications, your doctor may want to measure blood levels before surgery and again after to see if doses need to be adjusted. Monitoring of lithium is particularly important, because large changes in weight can affect how your kidneys clear lithium from your body. If you are planning weight loss surgery, you’ll want to discuss these issues with your health care providers well in advance. And you’ll want to make sure that your different health care providers (psychiatrist, therapist, surgeon) communicate clearly with each other. They will usually need your written permission to do that.