Headache after brain hemorrhage can occur in several ways: 1. After brain hemorrhage, the pressure inside the brain is particularly high, then headache will occur. The three manifestations of increased intracranial pressure are headache, vomiting, and optic papilloedema. If a headache occurs after a brain hemorrhage, it suggests that intracranial pressure may be elevated. 2. After a brain hemorrhage breaks into the ventricular system, the blood in the ventricular system will irritate the person’s meninges causing a headache, which is very intense. 3. There are other conditions, such as thalamic hemorrhage. After bleeding in the thalamus, it can cause sensory headache in the thalamus, or thalamic pain, which is a sensory allergy, and it causes a very strong headache.