It is quite common for people to experience the occasional headache, brought on by stress or sinus pressure. Many people suffer from constant daily headaches that do not go away. Some chronic headaches do not appear to have an underlying cause, according to MayoClinic.com. Physicians will run a series of tests to determine if an illness is the cause of the constant head pain.
Meningitis
Meningitis is an inflammation of the membranes surrounding the brain and spinal cord. Bacteria commonly causes most meningitis cases. According to the U.S. Centers for Disease Control and Prevention, characteristics of meningitis include a high fever, severe constant headache and stiffness in the neck caused by the swelling of the membranes in the brain and spinal cord. Other symptoms may include seizures, vomiting and nausea, extreme fatigue, sensitivity to light, lack of interest in eating or drinking and a skin rash.
Physicians commonly diagnose meningitis with a throat culture, x-ray or a spinal tap. A spinal tap, also known as a lumbar puncture, involves a physician removing a sample of spinal fluid from the spinal column and examining it for low sugar levels, an increased white blood cell count and increased proteins, all signs of meningitis. Physicians will treat acute bacterial meningitis with intravenous antibiotics. Antibiotics will not work on viral meningitis so physicians will often prescribe bed rest, fluids and over-the-counter pain medications. Patients experiencing viral meningitis due to a herpes outbreak, may be prescribed antiviral medications.
Intracranial Pressure
Increased cranial pressure is a rise in the pressure inside the skull as a result of an injury or illness. Increased intracranial pressure occurs when fluids, such as blood or cerebrospinal fluids, or swelling of the brain tissues restricts blood flow throughout the brain. This may be caused by a brain hemorrhage, brain tumor, meningitis, severe head injury, epilepsy or a hemorrhagic stroke, according to the National Institutes of Health. In adults, the symptoms of intracranial pressure include behavior changes, decreased consciousness, severe headache, lethargy, neurological problems, seizures and vomiting. In children, drowsiness, bulging at the top of the head and vomiting may occur. A sudden increased intracranial pressure is a medical emergency and requires immediate attention. Treatments often include breathing support, medications to help decrease swelling, draining of fluid from the brain and, in some cases, a temporary removal of part of the skull.
Brain Tumor
A brain tumor is a mass of abnormal cells in the brain, according to the MayoClinic.com. Brain tumors can be noncancerous or cancerous. Many brain tumors begin in the brain but spread, or metastasize, to other parts of the body. Symptoms of a brain tumor include headaches that gradually become more frequent or severe, unexplained nausea and vomiting, blurred or double vision or loss of peripheral vision, difficulty with balance, confusion, personality or behavior changes, seizures and hearing problems. Physicians diagnose brain tumors through a series of tests to analyze balance, vision, hearing, coordination and reflexes. Imaging tests and biopsies will help confirm a diagnosis of a brain tumor. Treatment of brain tumors is dependent on many different factors.
Physicians will often choose to remove tumors that are safely accessible by a surgeon. In cases where surgeons may not safely remove a tumor, radiation therapy often helps kill tumor cells and shrink tumors. In cancerous tumors, physicians may prescribe targeted drug therapy as well as chemotherapy to help kill the tumor cells.


