The reason why head CT is fine, but the patient still has headache is because it can exclude serious diseases such as subarachnoid hemorrhage, cerebral hemorrhage, intracranial occupancy, intracranial tumor, etc. The remaining ones, such as migraine, myotonic headache, cluster headache, are all episodic in nature, and CT will not reveal positive findings. This headache can be relieved by taking appropriate oral pain medication. The majority of functional headaches can be relieved clinically with medication or acupuncture. It is a major problem if the head CT is taken, so the patient should not be too nervous and anxious, and the symptomatic pain relief is sufficient. If symptoms such as vomiting occur during the headache, another timely visit to the doctor is needed.