About phenylbutyrate sodium
Ammonia-scavenging medicine
Used for
- Long-term treatment of urea cycle disorders that cause high blood ammonia
Usual adult dose
Usually 9.9–13.0 g/m² daily, divided into 3–6 doses; dosing is individualized.
Usual dose in children
Usually 450–600 mg/kg daily for infants and children under 20 kg; specialist-adjusted.
Common side effects
- Poor appetite, nausea, vomiting, or constipation
- Body odor or unpleasant taste
- Menstrual irregularities
- Abnormal blood tests, including low potassium or changes in blood counts
Important warnings
- For specialist-supervised treatment; stopping can rapidly raise blood ammonia.
- Monitor blood ammonia, electrolytes, blood counts, and liver and kidney function.
- Use caution with liver or kidney impairment and salt-sensitive conditions.
- Seek urgent care for confusion, unusual sleepiness, or worsening vomiting.
Pregnancy
Use only when clearly needed; uncontrolled ammonia can endanger both pregnant person and fetus.
Breastfeeding
Not well established; use requires specialist assessment.
Interactions
- Probenecid may reduce removal of phenylbutyrate metabolites.
- Valproate, haloperidol, and corticosteroids may increase ammonia or worsen control.
- Other medicines affecting kidney function or electrolytes may need monitoring.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.