What is Ammobula?

Ammobula is a prescription medication containing sodium phenylbutyrate, used for the management of urea cycle disorders (UCDs) in patients who cannot be managed by dietary protein restriction and amino acid supplementation alone. This FDA-approved treatment helps reduce elevated blood ammonia levels (hyperammonemia) that can occur in patients with urea cycle enzyme deficiencies.

Sodium phenylbutyrate works as a nitrogen-binding agent, providing an alternative pathway for waste nitrogen excretion in patients whose bodies cannot process ammonia normally. By preventing dangerous ammonia build-up, Ammobula helps protect the brain and other vital organs from ammonia toxicity.

How Ammobula Works

In healthy individuals, the urea cycle converts toxic ammonia into urea, which is then safely eliminated through urine. However, patients with urea cycle disorders lack or have reduced activity of specific enzymes needed for this process, leading to dangerous ammonia accumulation in the blood.

Ammobula provides an alternative mechanism for nitrogen disposal. Sodium phenylbutyrate is converted in the body to phenylacetate, which then conjugates with glutamine to form phenylacetylglutamine. This compound is readily excreted in the urine, effectively removing excess nitrogen and reducing ammonia levels without relying on the impaired urea cycle.

Who Should Take Ammobula?

Ammobula is indicated for patients diagnosed with urea cycle disorders, including but not limited to:

• Carbamyl Phosphate Synthetase (CPS) Deficiency
• Ornithine Transcarbamylase (OTC) Deficiency - the most common UCD
• Argininosuccinate Synthetase (ASS) Deficiency (Citrullinemia)
• Argininosuccinate Lyase (ASL) Deficiency (Argininosuccinic Aciduria)
• Arginase Deficiency (Hyperargininemia)

These genetic disorders can present at any age, from newborns to adults, and require lifelong management to prevent hyperammonemic crises that can lead to brain damage, coma, or death.

Product Specifications

Dosage and Administration

Standard Dosing:

• Adults and children weighing >20 kg: 9.9-13 g/m² body surface area per day
• Children weighing ≤20 kg: 450-600 mg/kg per day
• Maximum daily dose should not exceed 20 grams per day

The Ammobula powder are to be taken in equally divided amounts with each meal or feeding (i.e., three to six times per day). Ammobula Powder is indicated for oral use (via mouth, gastrostomy, or nasogastric tube) only. The powder is to be mixed with food (solid or liquid) for immediate use; however, when dissolved in water, Ammobula Powder has been shown to be stable for up to one week at room temperature or refrigerated. The effect of food on sodium phenylbutyrate has not been determined.

Administration Guidelines

• Powder is indicated for oral use (via mouth, gastrostomy, or nasogastric tube) only. Powder should not be administered via nasogastric or gastrostomy tubes without medical supervision
• Can be mixed with solid food (applesauce, oatmeal) or liquids

Monitoring Requirements

Patients taking Ammobula require regular monitoring including:

• Plasma ammonia levels
• Plasma amino acid levels (especially glutamine)
• Complete blood count
• Liver function tests
• Electrolytes and kidney function

Safety Information

Common Side Effects

The most frequently reported side effects include:

• Menstrual irregularities in women
• Decreased appetite
• Body odor (described as musty or unpleasant)
• Bad taste or altered taste perception
• Nausea and vomiting
• Abdominal pain
• Headache

Most side effects are dose-related and may improve with dosage adjustment or administration with food.

Serious Warnings

• Sodium Phenylbutyrate Oral Powder USP should be used with great care, if at all, in patients with congestive heart failure or severe renal insufficiency, and in clinical states in which there is sodium retention with edema.
• Use of corticosteroids may cause the breakdown of body protein and increase plasma ammonia levels.

Hyperammonemia: Even with treatment, breakthrough hyperammonemic episodes can occur, particularly during periods of increased protein intake, illness, or stress. Seek immediate medical attention if symptoms occur:

• Confusion or altered mental status
• Excessive sleepiness or lethargy
• Vomiting
• Loss of coordination
• Unusual behavior

Neurotoxicity: Sodium phenylbutyrate has been associated with neurotoxicity at high doses. Report any neurological symptoms to your healthcare provider immediately.

Contraindications

Ammobula should not be used in patients with:

• Known hypersensitivity to sodium phenylbutyrate or any formulation component
• Acute hyperammonemic encephalopathy (different treatment required)

Drug Interactions

Inform your healthcare provider about all medications you are taking. Important interactions include:

• Probenecid: May affect phenylacetate excretion
• Valproate: May increase ammonia levels
• Corticosteroids: May increase protein catabolism
• Haloperidol: Potential for increased side effects

Storage Requirements

• Store at room temperature between 15–30°C (59–86°F)
• Keep container tightly closed to protect from moisture
• Keep out of reach of children
• Do not use after expiration date

Product Pricing and Availability

• Available Pack Sizes: 100 g Sodium Phenylbutyrate oral powder USP is available in 250 cc bottles
• Pricing Information: ₹24,500
• Where to Purchase: Call customer care number: 7337585050
• Last Updated: November 27, 2025

Frequently Asked Questions (FAQ)

FDA Approval and Clinical Evidence

Ammobula (sodium phenylbutyrate) received FDA approval for the treatment of urea cycle disorders based on clinical studies demonstrating its effectiveness in reducing blood ammonia levels and preventing hyperammonemic episodes. Long-term studies have shown that continuous therapy with sodium phenylbutyrate, combined with dietary protein restriction and amino acid supplementation, significantly reduces the frequency and severity of hyperammonemic crises and improves survival and quality of life in patients with UCDs.

Clinical data supports the use of sodium phenylbutyrate across all age groups, from neonates to adults, with efficacy demonstrated in various types of urea cycle enzyme deficiencies. The medication has been used for over two decades in the management of these rare metabolic disorders.

Clinical data

Clinical evidence: Efficacy and safety of Sodium phenylbutyrate for the treatment of urea-cycle disorders

• Urea cycle disorders (UCDs) are a group of rare inborn errors of metabolism caused by a deficiency in one of the six enzymes or one of the two transporters involved in the urea cycle. Pharmacological treatment of urea-cycle disorders involves alternative nitrogen-scavenging pathways. Among the ammonia-scavenging drugs, sodium phenylbutyrate is a well-known long-term treatment of urea-cycle disorders.
• Sodium phenylbutyrate is clinically proven to be effective in managing urea-cycle disorders (UCDs) by helping to eliminate excess nitrogen and control hyperammonemia. Clinical evidence shows that NaPBA maintains ammonia control, prevents hyperammonemic crises, and has a well-established safety profile. Newer, taste-masked formulations (Ammobula) have demonstrated improved patient compliance and quality of life
• Ornithine transcarbamylase deficiency is a very heterogeneous urea cycle disorder resulting in hyperammonemia with various presentations from the neonatal period through adulthood. a retrospective study in nine patients (four male/five females, age at diagnosis ranging from 6 days to 14 years) to evaluate the safety and efficacy of sodium phenylbutyrate (Ammobula) in long-term treatment with Sodium Phenylbutyrate in ornithine transcarbamylase-deficient Patients.
• All patients were diagnosed by DNA mutational analysis and/or liver enzyme measurement. Sodium phenylbutyrate (median dose of 352 mg/kg/day) was administered at 8.9 and 4.9 years of age (median) in males and females, respectively. Researchers analysed clinical and biochemical data and the median follow-up duration was 26 months.
• During that time, there were no hyperammonemic episodes requiring hospitalization. Median plasma ammonia and glutamine levels were 30 and 902 μmol/L respectively. Total protein intake could be increased to 0.95 g/kg/day after 18 months. No side effects related to therapy were observed.
• This retrospective study confirms that the use of phenylbutyrate in patients with OTC deficiency is safe. It facilitates the clinical management of these patients and enhances their quality of life by achieving better metabolic control despite a higher intake of natural protein.

Safety

• Adverse events: No adverse effect was detected during the treatment period.
• Neurological status: Mostly stable; some mild deficits (e.g., ataxia, hyperactivity, speech delay).
• Liver & renal function: Normal throughout therapy.

Patient Support and Resources

Living with a urea cycle disorder requires comprehensive care involving metabolic specialists, dietitians, genetic counselors, and ongoing family education. Patients and families are encouraged to:

• Connect with patient advocacy organizations such as the National Urea Cycle Disorders Foundation
• Establish care with a metabolic genetics specialist experienced in UCD management
• Wear medical alert identification indicating the diagnosis
• Develop an emergency protocol letter to share with healthcare providers
• Join support groups to connect with other families affected by UCDs

Important Reminders

• Take Ammobula exactly as prescribed by your healthcare provider
• Do not adjust your dose without medical supervision
• Keep all scheduled appointments for monitoring
• Report any new symptoms or concerns promptly
• Store medication properly and check expiration dates
• Ensure adequate supply and refill prescriptions in advance
• Educate family members and caregivers about your condition and emergency signs