Nausea and vomiting after a fall on the head is mostly related to increased intracranial pressure, which can be caused by violence such as cerebral contusion, intracranial hematoma or skull fracture. 1. Cerebral contusion: the head is subjected to violence caused by organic brain damage, can form a cerebral contusion, light only minor symptoms, after the injury if the cerebrospinal fluid impact on the fourth ventricle at the bottom of the brain stem of the vomiting center, subarachnoid hemorrhage stimulation of the meninges, or vestibular system stimulation and other reasons can cause headache, nausea and vomiting symptoms. 2. Intracranial hematoma: If there is intracranial hematoma after craniocerebral injury, such as epidural hematoma, compression of brain tissue, there will be progressive impaired consciousness, and due to increased intracranial pressure, there can be nausea, vomiting and other symptoms in the middle of the waking period. 3. Skull fracture: when the skull is subjected to strong violence, fracture can occur, causing increased intracranial pressure, nausea, vomiting symptoms. If you have nausea and vomiting after a head injury, you should consult a doctor immediately, complete the examination, make a clear diagnosis and carry out appropriate treatment as soon as possible.