Classification: Clinical headache can be classified according to the mode of onset: ① Acute onset headache: such as subarachnoid hemorrhage and other cerebrovascular diseases, meningitis or encephalitis; ② Subacute onset headache: such as temporal arteritis, intracranial tumor; ③ Chronic onset headache: such as migraine, tension-type headache, cluster headache, drug-dependent headache, etc. According to the etiology of headache, the second edition of the International Classification of Headache Disorders developed by the International Headache Society in 2004, headache is divided into three major categories: ① Primary headache: including migraine, tension-type headache, cluster headache, etc.; ② Secondary headache: including head and neck trauma, craniocervical vascular factors, intracranial non-vascular diseases, infection, drug withdrawal, drug dependence, etc. (3) cranial neuralgia, central and primary facial pain, as well as headache caused by other facial structural lesions and other types of headache. The pathogenesis of headache is complex, but it is mainly caused by the stimulation of nociceptive receptors in intracranial and extracranial nociceptive structures, which are transmitted to the cerebral cortex via nociceptive transmission pathways. Intracranial nociceptive structures include venous sinus (such as sagittal sinus), anterior and middle meningeal arteries, dura mater at the base of the skull, trigeminal nerve (V), glossopharyngeal nerve (IX) and vagus nerve (X), proximal part of internal carotid artery and adjacent branches of Willis ring, gray matter around the midbrain conduction duct and thalamic sensory relay nucleus of the brainstem, etc. Extracranial nociceptive structures include periosteum of the skull, skin of the head, subcutaneous tissues, capillary tendon membrane, head and neck muscles and extracranial arteries. The extracranial pain-sensitive structures include the periosteum of the skull, the skin of the head, the subcutaneous tissue, the capillary tendons, the muscles and extracranial arteries of the head and neck, the 2nd and 3rd cervical nerves, the eyes, the ears, the teeth, the sinuses, the oropharynx and the nasal mucosa. Headaches can be caused by mechanical, chemical, biological stimuli and biochemical changes in the intracranial and extracranial pain-sensitive structures. For example, dilatation or traction of intracranial and external arteries, displacement or traction of intracranial veins and venous sinuses, compression, traction or inflammatory stimulation of cerebral and cervical nerves, spasm of cranial and cervical muscles, inflammatory stimulation or trauma, meningeal irritation caused by various reasons, abnormal intracranial pressure, dysfunction of intracranial 5-hydroxytryptaminergic neuronal projection system, etc. Pathophysiology: Head and facial blood vessels, nerves, meninges, venous sinuses, head and facial skin, subcutaneous tissues, mucous membranes, etc. constitute the pain-sensitive structures of the head, and head pain is triggered when they are subjected to mechanical pull, chemical or biological stimulation or changes in the internal environment. Clinical manifestations: The degree of headache varies from mild to severe, and the duration of pain varies from long to short. There are various forms of pain, such as distension, dullness, tearing pain, electric shock pain, pins and needles pain, some of which are accompanied by vascular pulsation and tightness of the head, as well as nausea, vomiting and dizziness. Secondary headache may also be accompanied by other systemic disease symptoms or signs, such as infectious disease often accompanied by fever, vascular disease often accompanied by hemiplegia, aphasia and other symptoms of neurological deficits. Depending on the severity of the headache, it can cause the patient to lose the ability to live and work. Diagnosis of headache: The diagnosis can be made based on the location of the pain in the patient’s head. In the process of headache diagnosis, it is important to distinguish whether the headache is primary or secondary. The diagnosis of primary headache should be based on the exclusion of secondary headache, as primary headache is a benign process, while secondary headache is caused by organic lesions. Since the etiology of headache is complex, in the history taking of headache patients, the focus should be on the mode of headache onset, frequency of attacks, attack time, duration, location, nature and degree of pain of headache, the presence of antecedent symptoms, and the presence of clear triggering factors, factors that aggravate and reduce headache, etc. At the same time, in order to better identify the cause and nature of headache, a comprehensive understanding of the patient’s age and gender, sleep and occupational status, past medical history and concomitant diseases, history of trauma, history of medication, history of poisoning and family history should be obtained to determine the effect of general conditions on the onset of headache. A thorough physical examination, especially the examination of the nervous system, cranium and five senses, can help to detect the lesions of headache. Timely and appropriate use of neuroimaging or lumbar cerebrospinal fluid examination can provide the basis for diagnosis and differential diagnosis of intracranial organic lesions. Headache treatment: It includes pharmacological treatment and non-pharmacological physical treatment. Treatment principles include symptomatic management and treatment of the primary cause. For acute attacks of primary headache and secondary headache whose etiology cannot be immediately corrected, symptomatic treatment such as analgesia can be given to terminate or alleviate the headache symptoms, and appropriate symptomatic treatment can also be given for the accompanying symptoms of headache such as vertigo and vomiting. For secondary headache with clear causes, the causes should be removed as soon as possible, such as anti-infection treatment for intracranial infection, dehydration to lower cranial pressure for intracranial hypertension, and surgery to remove intracranial tumor. 1.Medication: Analgesic drugs include: non-steroidal anti-inflammatory analgesics, central analgesics and narcotic analgesics. Non-steroidal anti-inflammatory painkillers have the advantages of exact efficacy and no addiction, so they are the most commonly used painkillers for headache, including aspirin, ibuprofen, anti-inflammatory pain, paracetamol, pautazone, rofecoxib, celecoxib, etc. Tramadol as the representative of central painkillers, belongs to the second class of psychotropic drugs, non-narcotic painkillers, the pain relief effect is stronger than the general antipyretic painkillers, mainly used for moderate and severe degree of headache and various post-operative and cancerous lesions pain, etc. Opioids such as morphine and dulcolax represent narcotic painkillers, which have the strongest pain-relieving effect, but long-term use can lead to addiction. These drugs are only used for patients with advanced cancer. Besides, there are also some herbal compound headache painkillers, which are helpful for relieving and preventing headache. 2.Non-pharmacological physiotherapy Non-pharmacological physiotherapy for headache includes: physical magnetic therapy, local cold (hot) compress, oxygen absorption, etc. Appropriate treatment should be given to those who have recurrent headache to control frequent headache attacks. Disease prevention The prevention and treatment of headache should reduce all possible causes of headache, including avoiding soft tissue injury to the head and neck, infection, avoiding contact with and intake of irritating food, avoiding mood swings, etc. Also, the primary diseases secondary to headache should be diagnosed and treated in a timely manner. Sedatives, antiepileptics and tricyclic antidepressants are effective in preventing primary headache attacks such as migraine and tension headache. Disease care Patients with headache should reduce pain-inducing foods such as chocolate, cheese, wine, coffee and tea. Also taste diet should be light, avoid spicy and stimulating, raw and cold foods, and foods such as ham, dried cheese, and long-preserved game should be prohibited during headache attacks.