Headache with dizziness could occur due to plenty of reasons ranging from dehydration to anxiety. Migraines are also a common cause of dizziness accompanied with headache. Although rare, a headache with dizziness can sometimes indicate a medical emergency, requiring immediate treatment. These emergency situations include brain aneurysm, stroke, head injuries, or bacterial and viral infections. It is best to seek advice from your doctor if your headache is often accompanied by dizziness.