The first day I increased my dose I felt a little anxious/fuzzy but the feeling has stopped since my body has gotten used to the medicine. Also, at first I took my first dose first thing in the morning. I felt a little nauseus/lightheaded so I adjusted to taking it with lunch instead and my second dose right before bed. I felt much better after that and I still take them approximately every 12 hrs like I am supposed to. Hope this helps! How long have you been taking the medicine?