From the Guidelines
Medications used to treat hyperammonemia include nitrogen-scavenging drugs such as sodium phenylbutyrate, sodium benzoate, and sodium phenylacetate, which help remove excess nitrogen from the body, as well as lactulose and rifaximin to reduce ammonia production by intestinal bacteria, with dosing varying based on the patient's age, weight, and specific condition 1.
Key Medications
- Nitrogen-scavenging drugs: sodium phenylbutyrate, sodium benzoate, and sodium phenylacetate
- Lactulose and rifaximin to reduce ammonia production by intestinal bacteria
- L-arginine and L-citrulline to improve urea cycle function in certain types of hyperammonemia
Treatment Approach
Treatment typically begins immediately upon diagnosis and may be lifelong for genetic causes, with the goal of providing alternative pathways for nitrogen excretion or enhancing the body's natural ammonia removal mechanisms 1.
Dosing and Administration
Dosing varies based on the patient's age, weight, and specific condition, with intravenous administration of sodium phenylacetate and sodium benzoate (Ammonul) for acute severe cases, and oral phenylbutyrate for urea cycle disorder diagnosis 1.
Additional Considerations
Dietary protein restriction and adequate caloric intake are also essential components of management, with prompt treatment crucial to prevent irreversible neurological damage if left untreated 1.
From the FDA Drug Label
Sodium Phenylbutyrate Powder is indicated as adjunctive therapy in the chronic management of patients with urea cycle disorders involving deficiencies of carbamylphosphate synthetase (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase (AS) Sodium Phenylbutyrate Powder aids the body in eliminating substances that produce ammonia.
The medications used to treat hyperammonemia include:
- Sodium phenylbutyrate 2
- Sodium phenylacetate (IV) 2 These medications help the body eliminate substances that produce ammonia, and are used as adjunctive therapy in the chronic management of patients with urea cycle disorders.
From the Research
Medications for Hyperammonemia
The following medications are used to treat hyperammonemia:
- Sodium phenylacetate and sodium benzoate: This combination has been shown to lower plasma ammonium levels and improve survival in patients with urea-cycle disorders 3, 4.
- Carbamyl glutamate: This medication can prevent the potentiation of ammonia toxicity by sodium benzoate and increase urea production 5.
- Lactulose: This medication can help reduce ammonia levels in patients with liver failure by reducing ammonia production, absorption, or elimination 6, 7.
- Rifaximin: This medication can also help reduce ammonia levels in patients with liver failure 6.
- Arginine hydrochloride: This medication can be used in conjunction with sodium phenylacetate and sodium benzoate to help lower plasma ammonium levels 3.
Additional Therapies
In addition to these medications, other therapies may be used to treat hyperammonemia, including:
- Hemodialysis: This can be used to control hyperammonemia, especially in neonates and older patients who do not respond to intravenous sodium phenylacetate and sodium benzoate 3, 4.
- Provision of adequate calories: This can help prevent catabolism and reduce ammonia production 3.
- Closure of large portosystemic shunts: This can help reduce ammonia levels in patients with liver failure 6.