Encephalopathy can be classified based upon the underlying pathophysiology.

There are many types of encephalopathy.

• Hepatic encephalopathy – Arising from advanced cirrhosis of the liver
• Hypoxic encephalopathy – Permanent or transitory encephalopathy arising from severely reduced oxygen delivery to the brain
• Wernicke’s encephalopathy – Arising from thiamine deficiency, usually in the setting of alcoholism
• Hashimoto’s encephalopathy – Arising from an auto-immune disorder
• Hypertensive encephalopathy – Arising from acutely increased blood pressure
• Metabolic encephalopathy
• Toxic Metabolic encephalopathy – A catch-all for brain dysfunction caused by infection, organ failure, or intoxication.
• Uremic encephalopathy – Arising from high levels of toxins normally cleared by the kidneys — rare where dialysis is readily available
• Mitochondrial encephalopathy – Metabolic disorder caused by dysfunction of mitochondrial DNA. It can affect many body systems, particularly the brain and nervous system.
• Glycine encephalopathy – A pediatric metabolic disorder
• Static encephalopathy – Unchanging, or permanent, brain damage
• Transmissible spongiform encephalopathy – A collection of diseases all caused by prions, and characterized by “spongy” brain tissue (riddled with holes), impaired locomotion or coordination, and a high fatality rate. It includes bovine spongiform encephalopathy (mad cow disease), scrapie, and kuru among others.
• HIV encephalopathy – Neurological manifestation of AIDS, seen in terminally ill patients