Hi . Have you had a chance to speak to your doctor about this issue yet? I can tell you that headache is considered to be a pretty common side effect (see here for example: https://www.goodrx.com/cimzia/most-cimzia-side-effects). That said, there could be other causes for your symptoms which is why it is important to get it checked. Hoping you can get some answers and relief and please feel free to keep us posted. Best, Richard (Team Member)