From the Guidelines
Lactulose is recommended as the primary treatment for hepatic encephalopathy in patients with liver cirrhosis, with a goal of achieving 2-3 bowel movements per day, as supported by the most recent guidelines from the European Association for the Study of the Liver (EASL) 1.
Key Considerations for Lactulose Prescribing and Monitoring
- The typical starting dose of lactulose is 25-30 mL orally two to three times daily, with dosing individualized and adjusted based on clinical response.
- For acute hepatic encephalopathy, higher initial doses may be used (30-45 mL every hour) until bowel evacuation occurs.
- Patients or caregivers should monitor stool frequency and consistency, mental status changes, and signs of dehydration or electrolyte imbalances.
- The dose should be reduced if diarrhea develops and increased if constipation occurs or encephalopathy symptoms persist.
- Regular clinical follow-up is essential to assess treatment efficacy and adjust dosing as needed, as emphasized in the EASL guidelines 1 and supported by other studies 1.
Rationale for Lactulose Use
- Lactulose works by acidifying the colon, which traps ammonia as ammonium and reduces its absorption, thereby decreasing blood ammonia levels that contribute to encephalopathy.
- The use of lactulose has been shown to be effective in preventing overt episodes of hepatic encephalopathy, with a beneficial effect demonstrated in a systematic review and network meta-analysis of 1,828 participants 1.
Additional Considerations
- Rifaximin may be added to lactulose as an adjunct therapy for secondary prophylaxis following multiple episodes of overt hepatic encephalopathy, as recommended by the EASL guidelines 1 and supported by other studies 1.
- Patients should be educated about potential side effects of lactulose, including abdominal cramping, bloating, flatulence, and diarrhea, which often improve with continued use or dose adjustment.
From the FDA Drug Label
The usual adult dosage is 10 g to 20 g of lactulose daily. The dose may be increased to 40 g daily if necessary. Twenty-four to 48 hours may be required to produce a normal bowel movement. The guidelines for lactulose prescribing in patients with liver cirrhosis are to start with a dose of 10 g to 20 g daily and increase to 40 g daily if necessary.
- The dose should be adjusted based on the patient's response to treatment.
- Monitoring should focus on the patient's bowel movement, with the expectation of a normal bowel movement within 24 to 48 hours after initiation of treatment 2.
From the Research
Lactulose Prescribing and Monitoring in Liver Cirrhosis
- Lactulose is the first-line treatment for acute overt hepatic encephalopathy (HE) in patients with liver cirrhosis 3.
- To prevent HE recurrence, lactulose plus rifaximin is recommended 3.
- Prophylactic lactulose therapy reduces the incidence of HE after acute upper gastrointestinal bleeding (AUGIB) in patients with cirrhosis, but has no effect on mortality 4.
- The use of lactulose for primary prophylaxis of HE in patients with cirrhosis and AUGIB has been debated, but studies suggest it may be beneficial 4.
Guidelines for Lactulose Prescribing
- Lactulose is typically started at a dose of 25-30 mL twice daily, with adjustments made to achieve 2-3 soft stools per day 4.
- Patients with cirrhosis and HE often require long-term lactulose therapy to prevent recurrence 3, 5.
- Rifaximin add-on to lactulose has been shown to improve health-related quality of life and reduce HE recurrence in patients with cirrhosis 6, 5.
Monitoring of Lactulose Therapy
- Patients on lactulose therapy should be monitored for signs of overt HE, such as impaired cognition, confusion, and personality changes 3.
- Serum ammonia levels should be checked regularly to assess the effectiveness of lactulose therapy 5.
- Patients should also be monitored for adverse events, such as diarrhea and abdominal discomfort, which are common with lactulose therapy 4.