L-ornithine-L-aspartate

Severe (serum creatinine >3 mg/dL): Contraindicated.

Granules for oral solution: Dissolve sachet contents in a glass of fluid (e.g. water, juice, tea).

Severe renal impairment (serum creatinine >3 mg/dL).

Pregnancy and lactation.

Significant: Nausea, vomiting; increased risk for dental caries (long-term use).
Gastrointestinal disorders: Abdominal distress, abdominal pain, diarrhoea, flatulence.
Musculoskeletal and connective tissue disorders: Very rarely, limb pain.

Monitor serum and urine urea levels (with high doses).

Description:
Mechanism of Action: L-ornithine-L-aspartate exerts its effects through ornithine and aspartate. Ornithine and aspartate are amino acids that help reduce plasma ammonia concentrations via 2 key methods of ammonia detoxification, urea synthesis and glutamine synthesis. Ornithine acts as both an activator of ornithine carbamoyl transferase and carbamoyl phosphate synthetase in periportal hepatocytes, as well as a substrate for urea synthesis. Aspartate and other dicarboxylates, including metabolic products of ornithine, are absorbed by cells, where they are utilised to bind ammonia in the form of glutamine.
Pharmacokinetics:
Absorption: Rapidly absorbed. Bioavailability: 82.2 ± 28%. Time to peak plasma concentration: L-ornithine: 30-60 minutes.
Distribution: Rapidly distributed.
Excretion: Via urine (urea as major product; some aspartate are excreted unchanged). Elimination half-life: 0.3-0.4 hours.

Store below 30°C.

Cholagogues, Cholelitholytics & Hepatic Protectors

Butterworth RF, Kircheis G, Hilger N, McPhail MJW. Efficacy of L-Ornithine L-Aspartate for the Treatment of Hepatic Encephalopathy and Hyperammonemia in Cirrhosis: Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Clin Exp Hepatol. 2018 Sep;8(3):301-313. doi: 10.1016/j.jceh.2018.05.004. Accessed 24/02/2025. PMID: 30302048

Brayfield A, Cadart C (eds). Ornithine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 05/02/2025.

Hepa-Merz 3,000 mg Granulate/Sachet for Oral Solution (Merz Malaysia Sdn. Bhd.). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my. Accessed 05/02/2025.

L-Ornithine-L-Aspartate. UpToDate Lexidrug, Lexi-Drugs Multinational Online. Waltham, MA. UpToDate, Inc. https://online.lexi.com. Accessed 05/02/2025.