... multiple blood tests, MRI ect and no doctor could find anything wrong. After trying many medications I finally was prescribed lexapro. I started to feel better but have experienced weight gain. I recently stopped taking lexapro and my original feelings of brain fog and lightheaded feeling came back full force. I have always had very low blood pressure. Has anyone taken a different ssri that has helped them with brainfog/lightheaded feeling with out the weight gain??