TREATMENT OF EXCESSIVE AMMONIA LEVELS IN HEPATIC INSUFFICIENCY
Alcohol’s harmful effects on liver cells not only interfere with the normal functioning of the liver but also impact distant organs, including the brain. Prolonged liver damage resulting from excessive alcohol consumption can lead to the development of a serious and potentially fatal brain disorder known as hepatic encephalopathy, which is believed to be due to excess circulating ammonia levels.
Hepatic encephalopathy is a complication of cirrhosis of the liver and is characterized by a spectrum of psychiatric abnormalities such as personality changes, deterioration of mental status, impaired memory, and sensory abnormalities. Clinical manifestation can range from subtle memory problems to coma. Hepatic encephalopathy occurs in about 30%-45% of patients with cirrhosis.
PHARMACOLOGICAL MECHANISMS OF TREATMENT:
- sugar molecules to decrease systemic absorption of ammonia OR
- antibiotics to reduce the bacteria which produce ammonia in the gastrointestinal tract
- correct low potassium, since low potassium levels increases renal ammonia production.
- Lactulose (Chronulac, Constulose®) makes the colon contents more acidic, which prevents absorption of ammonia.
- The laxative action of lactulose moves the ammonia ions out of the colon, by stimulating bowel movements.
- Your Thompson Pharmacist will provide you with a measuring device to get an accurate dose of lactulose.
DOSE: oral dose of 15–30 ml twice daily
EXPECT 3-4 loose bowel movements per day
PRECAUTIONS: Overdosage can result in severe diarrhea, electrolyte disturbances, and dehydration, which may induce a flare of encephalopathy symptoms
Rifaximin (Xifaxan 550)
oral antibiotic agent with minimal gut absorption that concentrates in the GI tract. It has a broad-spectrum activity but doesn’t get absorbed out of the gut. Are usually added to lactulose, not instead of lactulose.
DOSE: Rifaximin, oral dose of 550 mg twice daily
Less commonly used antibiotics:
- Is a older non-absorbable antibiotic that decreases the ammonia forming bacteria in the gut.
- DOSE: oral dose of 500 mg four times daily (use high doses with caution). High doses may cause hearing loss and kidney damage.
Avoid medications that depress central nervous system function, especially benzodiazepines, like Valium, Xanax and Ativan.
Your Thompson Pharmacist is a great resource for vitamins, drugs to help curb drinking and drugs to manage hepatic encephalopathy. Go Ahead and ASK, at Thompson Pharmacy it’s all for you!