Sodium Phenylbutyrate
Buphenyl (sodium phenylbutyrate) is a prescription medication used to manage urea cycle disorders (UCDs), a group of rare genetic conditions where the body cannot properly remove ammonia from the blood. It works by providing an alternative pathway for nitrogen excretion, helping to lower dangerously high ammonia levels in patients with chronic UCDs.
Buphenyl is a nitrogen-binding agent used to treat urea cycle disorders by helping the body eliminate excess nitrogen through alternative pathways.
Key facts at a glance
- RxNorm
- 215778
- Generic
- Buphenyl
- Class
- brand-name
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Buphenyl is indicated for the chronic management of urea cycle disorders (UCDs), including carbamoyl phosphate synthetase I deficiency, ornithine transcarbamylase deficiency, and citrullinemia, in patients with hyperammonemia.
Buphenyl is metabolized to phenylacetate, which conjugates with glutamine to form phenylacetylglutamine, a compound that is excreted in urine. This provides an alternative pathway for nitrogen elimination, reducing the accumulation of ammonia in the blood.
Buphenyl must be used in conjunction with dietary protein restriction and should not be used for acute hyperammonemic crises. Common side effects may include decreased appetite, nausea, and menstrual irregularities. It is contraindicated during pregnancy and should be stored at room temperature. Regular monitoring of ammonia and amino acid levels is required during treatment.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed September 3, 2026. · Read our editorial policy