Maximum Infusion Rate for L-Ornithine L-Aspartate in Hepatic Encephalopathy
The standard intravenous dose of L-ornithine L-aspartate (LOLA) is 20-30 g/day dissolved in 250 mL of 5% dextrose or fructose solution and infused over 4 hours, which translates to a maximum infusion rate of approximately 62.5 mL/hour. 1, 2, 3
Recommended Dosing Protocol
Standard Intravenous Administration
- Dose: 20-30 g/day is the established therapeutic dose for hepatic encephalopathy 1, 4, 5
- Dilution: Dissolve in 250 mL of 5% dextrose water or fructose solution 2, 3
- Infusion duration: Administer over 4 hours daily 2, 3
- Treatment course: Continue for 5-7 consecutive days 2, 6, 3
Calculating the Maximum Rate
- When using 30 g LOLA in 250 mL solution infused over 4 hours, the infusion rate is 62.5 mL/hour 2, 3
- When using 20 g LOLA in 250 mL solution infused over 4 hours, the infusion rate is also 62.5 mL/hour 2, 3
Clinical Evidence Supporting This Rate
The 4-hour infusion protocol has been validated in multiple high-quality randomized controlled trials:
- A 2018 double-blind RCT of 193 patients demonstrated that 30 g/day LOLA infused over this timeframe significantly improved mental state grades within 1-4 days and reduced time to recovery compared to placebo 6
- A 1997 placebo-controlled trial of 126 patients used 20 g/day infused over 4 hours and showed significant improvements in ammonia levels and mental state 3
- A 2008 RCT confirmed efficacy with 20 g/day infused over 4 hours for 5 consecutive days 2
Important Clinical Considerations
Combination Therapy
- LOLA should be administered as add-on therapy to lactulose, not as monotherapy 1, 4, 6
- The combination leads to faster recovery (mean 1.92 days vs 2.50 days with lactulose alone) 6
Safety Profile
- The 4-hour infusion protocol has demonstrated excellent safety with minimal adverse events (only 5% experiencing mild gastrointestinal disturbances) 3
- No serious adverse events were reported at these infusion rates 2, 6, 3