Intracranial hypertension occurs when the pressure inside of the skull increases to abnormal levels. The causes of this condition vary, and in some cases there is no clear cause at all. Benign, or idiopathic, intracranial hypertension--sometimes called pseudotumor cerebri--is a condition in which symptoms falsely suggest a brain tumor; however, there is no tumor and no obvious underlying cause. Secondary intracranial hypertension is caused by an identifiable disease, head trauma or drug side effect.
Cerebrospinal Fluid
The brain and spinal cord are surrounded by cerebrospinal fluid--a liquid that protects and cushions the brain, carries away waste products and reduces pressure at the base of the brain by making it more buoyant. According to the Mayo Clinic, benign intracranial hypertension, or pseudotumor cerebri, may sometimes occurs as a result of a buildup of cerebrospinal fluid in the skull. While the fluid normally drains back into the bloodstream, absorption problems can lead to excess fluid and pressure in the skull cavity.
Blood Flow Blockage
According to the Merck Manuals Online Medical Library, idiopathic intracranial hypertension may sometimes occur when the large veins called venous sinuses that transport blood away from the brain become blocked. The increased force of blood trying unsuccessfully to make its way through the blocked veins causes pressure to increase within the skull cavity.
Medications
A number of medications can increase the risk for developing intracranial hypertension. Birth control pills, anabolic steroids or prescription corticosteroids, the breast cancer treatment drug Tamoxifen, the antiepileptic drug Phenytoin and lithium--a drug used to treat symptoms of mania among those with bipolar disorder--are some of the drugs that have been identified as secondary causes of intracranial hypertension, according to the National Institutes of Health.
According to the Merck Manuals, children who take excessive doses of vitamin A or who have recently taken the antibiotic tetracycline may also be at increased risk of developing intracranial hypertension.
Trauma and Disease
According to the Intracranial Hypertension Research Foundation, secondary intracranial hypertension may be caused by head trauma, such as a car accident, sports injury or other blow to the head. A number of diseases can also cause the brain to swell or adversely affect absorption of cerebrospinal fluid, thereby causing intracranial pressure to increase. Some of these diseases include syphilis, malaria, Lyme disease, human immunodeficiency virus (HIV), meningitis, mononucleosis and encephalitis--a type of brain inflammation caused by a virus.
