Proglycem

Proglycem is the brand name for glycerol phenylbutyrate, a nitrogen scavenger used in the long-term management of hyperammonemia associated with urea cycle disorders (UCDs). UCDs are genetic conditions in which the body cannot efficiently remove ammonia, a toxic byproduct of protein metabolism. Proglycem provides an alternative pathway for nitrogen excretion to help reduce elevated blood ammonia levels.

The drug acts as a prodrug that is broken down in the body to phenylbutyrate, which is then converted to phenylacetate. Phenylacetate binds to the amino acid glutamine to form phenylacetylglutamine, which is excreted in the urine. This process helps remove excess ammonia from the bloodstream and supports metabolic stability in patients with UCDs.

Proglycem is prescribed as part of a comprehensive treatment plan that often includes dietary protein management and other therapies. It is taken orally as an solution, with meals to improve tolerability. Dosing is individualized based on body weight and age and adjusted according to laboratory measurements of ammonia and clinical response. Proper administration typically requires a dosing device to ensure accuracy.

Common adverse effects reported with Proglycem include gastrointestinal symptoms such as nausea, vomiting, diarrhea, abdominal pain, and reduced appetite. Less frequently, hypersensitivity reactions may occur. Healthcare providers monitor ammonia levels, liver and kidney function, and growth or development in patients receiving therapy, and they assess potential drug interactions with other nitrogen scavengers or concurrent treatments.

Proglycem is one of several nitrogen-scavenging agents used in UCD management, alongside sodium phenylbutyrate–based therapies and glycerol phenylbutyrate products.