Hepatic Encephalopathy

Key facts

• Hepatic encephalopathy (HE) is a decline in brain function caused by toxin buildup, mainly ammonia, when a damaged liver can no longer filter it from the blood. Symptoms range from mild confusion and forgetfulness to disorientation and, in severe cases, loss of consciousness.
• It occurs mostly in people with cirrhosis. Episodes are usually set off by a specific trigger: gastrointestinal bleeding, infection, constipation, dehydration, or certain medicines.
• Treatment targets the trigger and lowers ammonia, usually with rifaximin, a gut-acting antibiotic that reduces the ammonia-producing bacteria in the intestine. A laxative such as lactulose is often used alongside it to clear toxins faster.
• Persistent or worsening confusion, difficulty staying awake, or any rapid change in mental state needs urgent medical attention.

What drives the confusion

The liver normally converts ammonia, a by-product of protein digestion, into urea that the kidneys excrete. When liver function is severely compromised, ammonia accumulates in the blood and crosses into the brain, where it disrupts normal neural signaling. Common triggers include gastrointestinal bleeding, infection, constipation, dehydration, and certain medicines, sedatives in particular. Finding and treating the trigger matters as much as managing the confusion itself, since an episode rarely happens without one.

Reducing ammonia with targeted treatment

The main goal of treatment is lowering ammonia levels and preventing further episodes. Rifaximin is a minimally absorbed antibiotic that works within the gut rather than the bloodstream, cutting down the bacteria responsible for much of the ammonia load. It is widely used long term to prevent repeat episodes in people who have already had one. Treating constipation and staying well hydrated also help the body clear toxins.

When to see a doctor

Persistent or worsening confusion, inability to stay awake, or any rapid change in mental state warrants urgent medical attention. Anyone with known liver disease who develops new drowsiness or a personality change should be assessed the same day, since treating the underlying trigger promptly can reverse an episode quickly.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.