A coma is a prolonged state of unconsciousness that can be caused by a number of problems relating to the brain including: traumatic head injury, stroke, brain tumor and drug or alcohol intoxication. Types of comas include toxic-metabolic encephalopathy (acute condition of brain dysfunction), anoxic brain injury (lack of oxygen to the brain), persistent vegetative state, locked-in syndrome (rare neurological condition), brain death (cessation of all brain function) and medically-induced (used to protect the brain from swelling after an injury). Though treatment for a coma depends on the cause, comas are considered medical emergencies and swift action must be taken to preserve life and brain function. Treatment may include antibiotics (for brain infection), glucose therapy (for diabetic shock), medication for seizures, surgery to remove a tumor and life support for individuals in intensive care. Organizations exist to provide support and resources for individuals and families affected by comas.