NDC 75987-0070-09 — Buphenyl sodium phenylbutyrate .94 g/g Powder

🆔 Identity & classification

FDA NDC (as labeled) 75987-070-09

Product NDC 75987-070

11-digit billing NDC 75987007009

NCPDP billing unit GM — per gram (weight)

RxCUI 199369, 213196, 984105, 984107

UNII NT6K61736T

Application # NDA020573

SPL Set ID 463a36fa-3eb2-4326-8bd0-c8c7a11bca3a

Established class (EPC) Nitrogen Binding Agent

Mechanism of action Ammonium Ion Binding Activity

DEA schedule Non-controlled

Marketing category NDA

Marketing status On market

FDA listing status Listed (active directory)

Marketing start 1996-04-30

Route ORAL

Dosage form POWDER

Substance SODIUM PHENYLBUTYRATE

GPI-14 30908060002950

GPI class Buphenyl

GCN Seq No 026631

GCN 43370

HICL code 011317

Ingredient (HICL) Sodium Phenylbutyrate

HIC1 code D

Therapeutic class — broad (HIC1) Biliary System/Gastro-Intestinal System

HIC2 code D9

Therapeutic class — intermediate (HIC2) Ammonia Inhibitors

HIC3 code D9A

Therapeutic class — specific (HIC3) Ammonia Inhibitors

AHFS code 40:10.00.00

AHFS class Ammonia Detoxicants

FDB label name BUPHENYL POWDER

FDB brand name Buphenyl

Legend status F — Federal legend — prescription drug or device

Why two NDCs? The FDA registers this code as 75987-070-09 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 75987-0070-09. Same drug, same package — only the format differs.

Where does this data come from?

Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

🏷️ RxNorm drug class

This medicine belongs to the Nitrogen Binding Agent class.

Pharmacologic class Nitrogen Binding Agent

Drug family (ATC) Various alimentary tract and metabolism products

How it works Ammonium Ion Binding Activity

Where does this data come from?

Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

🏭 Manufacturer & labeler

LabelerHorizon Therapeutics USA, Inc.

Application holderHORIZON THERAPEUTICS US HOLDING LLC

FDA applicationNDA020573 (NDA)

Labeler code75987

First marketedApr 1996

Product typeHuman Prescription Drug

Portfolio12 products on file

🔎 All NDCs from Horizon Therapeutics USA, Inc.

The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).

Where does this data come from?

Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

🩺 Clinical

Label name BUPHENYL POWDER Ingredient Sodium Phenylbutyrate

Patient education

📘 MedlinePlus patient leaflet ↗

Supplement & herbal interactions

Some supplements/herbs that may interact with Sodium Phenylbutyrate — tap one for details:

Activated CharcoalMajor Coffee CharcoalModerate European MandrakeModerate GlucomannanModerate Guar GumModerate Gum ArabicModerate Slippery ElmModerate TragacanthModerate

🌿 Every supplement checked against Sodium Phenylbutyrate (19 interactions) — ranked by severity →

Where does this data come from?

Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

💊 What it looks like

Color White

ShapeOval

ImprintUCY;500

Size16 mm

ScoringNot scored

One label can cover several strengths, so colors may be combined — always confirm a loose pill against the dispensed prescription label or a pharmacist.

Where does this data come from?

Physical description (imprint, shape, color, scoring, coating) from this product’s FDA Structured Product Labeling (SPL), mirrored from DailyMed / openFDA.

🧪 Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

UNII 776XM7047L
Calcium stearate is a white powder derived from stearic acid and calcium. It works as a lubricant and glidant to help the medicine flow smoothly during manufacturing and prevent ingredients from sticking to equipment.
UNII ETJ7Z6XBU4
Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.

2 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?

Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?

No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.

Why might an inactive ingredient be missing?

Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.

Can inactive ingredients matter?

Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

💲 Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price system	Per g	Per package
Retail pharmacies payNADAC · weekly	Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo	$48.50	$12,126.03 / 250 g
Medicare drug plans payPart D · quarterly	No Part D plan price is available for this NDC in our data.

Where does this data come from?

NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

🔁 Therapeutic equivalents

Product	Labeler	Pack	NADAC/unit	TE	Status	Price vs. this
Sodium Phenylbutyrate .94 g/g 42794-0086-14	Sigmapharm	1 bottle	—	—	Discontinued	—
Sodium Phenylbutyrate .94 g/g 49884-0006-04	Par	1 bottle	—	—	FDA listed	—
Buphenyl .94 g/gthis 75987-0070-09	Horizon	1 bottle	—	—	FDA listed	—

About this product: this is the brand-name version. Some generic versions are approved by the FDA, but we could not confirm current pharmacy availability from our pricing/market data.

Where does this data come from?

Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

⏳ Availability & generic status

🏛️

1996

On the market since

Apr 1996

📍

2026

Currently FDA-listed

30 years listed

🔒

·

Generic approved (availability unconfirmed)

see note

🔒Generic approved by FDA, but pharmacy availability is not confirmed

The FDA lists approved generic versions of this medicine, but that does not always mean a pharmacy can get one today. Patent rules, launch agreements, supply and pricing can affect when generics actually arrive.

Where does this data come from?

Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

🗺️ Medicaid utilization & spend

📍 This exact package only: Medicaid data is reported per full 11-digit NDC — labeler, product and pack size — so every number here is for 75987-0070-09, not the drug overall. Other pack sizes report separately.

💊 Pharmacy benefit only: These are Medicaid outpatient pharmacy claims, billed by NDC. They exclude the medical benefit — clinic- or hospital-administered drugs billed under HCPCS J-codes — so drugs used mostly that way (e.g. Avastin, Lucentis, Keytruda) can look low or missing here. That’s expected, not an error.

📅 Q1 2025 – Q4 2025 · 4 quarters of data

ⓘ The newest quarter is usually incomplete when first published; states restate recent quarters in later CMS releases, so the latest figures typically revise upward. State coverage-policy changes can also shift quarter-to-quarter totals.

Prescriptions last 4 qtrs

43

Units reimbursed last 4 qtrs

16.5K

Gross reimbursed last 4 qtrs

$799.9K

Avg / prescription

$18,603.02

Avg / unit

$48.5041

Latest quarter Q4 2025

0Rx

Fee-for-service vs managed care ⓘ

100% MCO

Fee-for-service · 0 Rx Managed care · 43 Rx

State Medicaid map

Units reimbursed · per 100k residents

72.972.9

gray = no data reported ⓘ

Colors are per 100,000 residents, so big states don’t automatically dominate. Tap or hover a state for its actual totals.

Tap or hover a state

…for its Medicaid breakdown

🏆 Top states by units · per 100k residents

1 Florida 72.9 /100k

National units — by quarter

💵 About the dollar figures: “reimbursed” is what Medicaid paid pharmacies before confidential manufacturer rebates, so the program’s real net cost is lower than these numbers. Fee-for-service and managed-care claims are combined unless split above. Source: CMS State Drug Utilization Data; per-100k rates use 2023 Census population estimates.

📊 Medicare Part D spend CMS · PART D · 2025 (Q1-Q4)

Medicare Part D (outpatient prescription) spending for Buphenyl — the program that covers self-administered drugs. 1 manufacturer.

⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Buphenyl. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.

Total Part D spend

$1.64M

Claims incl. refills

50

Beneficiaries

—

Spend / beneficiary

—

Spend / claim

$32,741.27

💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

🔬 Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for Sodium phenylbutyrate — the ingredient across all brands.

Top reported reactions

Hyperammonaemia56

Vomiting42

Death35

Ammonia Increased32

Nausea28

Diarrhoea27

Decreased Appetite25

Reporter sex

Serious outcomes

Hospitalization164

Death84

Life-threatening13

Disabling7

Reports over time (by year) — tap or hover for the count & year

Most recent year is provisional (FAERS lags ~3 months).

Where does this data come from?

Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

📦 Packaging — all sizes for this product

Package NDC	Description	Marketing start	Status
75987-0070-09 You're viewing this	1 BOTTLE in 1 CARTON (75987-070-09) / 250 g in 1 BOTTLE	1996-04-30	Active

🧭 About this NDC listing & data coverage

Finished prescription product

What data is (and isn’t) available for this NDC — tap to expand

NDC identity (package / product / labeler codes)	✓ Available
Labeler	✓ Available
Product & package description	✓ Available
Marketing category & status	✓ Available
Active ingredient / dosage form / route	✓ Available
FDA label (SPL via DailyMed)	✓ Available
Package photos	✓ Available
Inactive ingredients (structured)	✓ Available
NADAC pharmacy acquisition price (CMS)	— Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data	— Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope.
HCPCS J-code billing crosswalk	— Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD)	✓ Available

“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?

The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.

Is the NDC printed on the package the same as the 11-digit billing NDC?

Yes, they identify this exact package in different formats. The FDA registers it as 75987-070-09, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 75987-0070-09, written without dashes as 75987007009. The Identity section at the top of this page lists every form of this code.

What do the three segments of this NDC mean?

In 75987-0070-09, the first segment (75987) is the labeler code FDA assigned to Horizon Therapeutics USA, Inc.; the middle segment (0070) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (09) identifies this exact package size and type. Together they name one specific package of one specific product.

Is this package still being marketed?

Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by Horizon Therapeutics USA, Inc.. Listing status can change — the directory data on this page refreshes weekly.

Who lists this product with the FDA?

Horizon Therapeutics USA, Inc. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.

Do I need a prescription for this product?

This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.

This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.

Where does this data come from?

Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.

🎯 Indications and Usage ⏱️ Dosage and Administration ⛔ Contraindications ⚠️ Warnings 🤒 Adverse Reactions 🤰 Pregnancy 🧒 Pediatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 📦 How Supplied / Storage and Handling 📋 Description 💬 Information for Patients

🎯 Indications and Usage ~2 min read ▾

INDICATIONS AND USAGE BUPHENYL is indicated as adjunctive therapy in the chronic management of patients with urea cycle disorders involving deficiencies of carbamoyl phosphate synthetase (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase (AS). It is indicated in all patients with neonatal-onset deficiency (complete enzymatic deficiency, presenting within the first 28 days of life). It is also indicated in patients with late-onset disease (partial enzymatic deficiency, presenting after the first month of life) who have a history of hyperammonemic encephalopathy.

It is important that the diagnosis be made early and treatment initiated immediately to improve survival. Any episode of acute hyperammonemia should be treated as a life-threatening emergency. BUPHENYL must be combined with dietary protein restriction and, in some cases, essential amino acid supplementation.

(See Nutritional Supplementation subsection of the DOSAGE AND ADMINISTRATION section.) Previously, neonatal-onset disease was almost universally fatal within the first year of life, even when treated with peritoneal dialysis and essential amino acids or their nitrogen-free analogs. However, with hemodialysis, use of alternative waste nitrogen excretion pathways (sodium phenylbutyrate, sodium benzoate, and sodium phenylacetate), dietary protein restriction, and, in some cases, essential amino acid supplementation, the survival rate in newborns diagnosed after birth but within the first month of life is almost 80%.

Most deaths have occurred during an episode of acute hyperammonemic encephalopathy. Patients with neonatal-onset disease have a high incidence of mental retardation. Those who had IQ tests administered had an incidence of mental retardation as follows: ornithine transcarbamylase deficiency, 100% (14/14 patients tested); argininosuccinic acid synthetase deficiency, 88% (15/17 patients tested); and carbamoyl phosphate synthetase deficiency, 57% (4/7 patients tested).

Retardation was severe in the majority of the retarded patients. In patients diagnosed during gestation and treated prior to any episode of hyperammonemic encephalopathy, survival is 100%, but even in these patients, most subsequently demonstrate cognitive impairment or other neurologic deficits. In late-onset deficiency patients, including females heterozygous for ornithine transcarbamylase deficiency, who recover from hyperammonemic encephalopathy and are then treated chronically with sodium phenylbutyrate and dietary protein restriction, the survival rate is 98%.

The two deaths in this group of patients occurred during episodes of hyperammonemic encephalopathy. However, compliance with the therapeutic regimen has not been adequately documented to allow evaluation of the potential for BUPHENYL and dietary protein restriction to prevent mental deterioration and recurrence of hyperammonemic encephalopathy if carefully adhered to. The majority of these patients tested (30/46 or 65%) have IQ's in the average to low average/borderline mentally retarded range.

Reversal of preexisting neurologic impairment is not likely to occur with treatment and neurologic deterioration may continue in some patients. Even on therapy, acute hyperammonemic encephalopathy recurred in the majority of patients for whom the drug is indicated. BUPHENYL may be required lifelong unless orthotopic liver transplantation is elected.

(See CLINICAL PHARMACOLOGY, Pharmacodynamics subsection for the biochemical effects of BUPHENYL).

⏱️ Dosage and Administration ~3 min read ▾

DOSAGE AND ADMINISTRATION For oral use only. The use of BUPHENYL Tablets is indicated for children weighing more than 20 kg and for adults. The usual total daily dose of BUPHENYL Tablets and Powder for patients with urea cycle disorders is 450–600 mg/kg/day in patients weighing less than 20 kg, or 9.9–13.0 g/m2/day in larger patients.

The tablets and powder are to be taken in equally divided amounts with each meal or feeding (i.e., three to six times per day). BUPHENYL 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, BUPHENYL Powder has been shown to be stable for up to one week at room temperature or refrigerated.

Sodium phenylbutyrate is very soluble in water (5 grams per 10 mL). When BUPHENYL Powder is added to a liquid, only sodium phenylbutyrate will dissolve, the excipients will not. The effect of food on sodium phenylbutyrate has not been determined.

Each level teaspoon (enclosed) dispenses 3.2 grams of powder and 3.0 grams of sodium phenylbutyrate. Each level tablespoon (enclosed) dispenses 9.1 grams of powder and 8.6 grams of sodium phenylbutyrate. Shake lightly before use.

The safety or efficacy of doses in excess of 20 grams (40 tablets) per day has not been established. NUTRITIONAL MANAGEMENT To promote growth and development, plasma levels of ammonia, arginine, branched-chain amino acids, and serum protein should be maintained within normal limits while plasma glutamine is maintained at levels less than 1,000 µmol/L. Minimum daily protein intake for a patient of a particular age should be taken from, for example, "Recommended Dietary Allowances", 10th ed., Food and Nutrition Board, National Academy of Sciences, 1989.

The allocation of dietary nitrogen into natural protein and essential amino acids is a function of age, residual urea cycle enzyme activity, and the dose of sodium phenylbutyrate. At the recommended dose of sodium phenylbutyrate, it is suggested that infants with neonatal-onset CPS and OTC deficiencies initially receive a daily dietary protein intake limited to approximately 1.6 g/kg/day for the first 4 months of life. If tolerated, the daily protein intake may be increased to 1.9 g/kg/day during this period.

Protein tolerance will decrease as the growth rate decreases, requiring a reduction in dietary nitrogen intake. From 4 months to 1 year of age, it is recommended that the infant receive at least 1.4 g/kg/day, but 1.7 g/kg/day is advisable. From 1 to 3 years of age, the protein intake should not be less than 1.2 g/kg/day; 1.4 g/kg/day is advisable during this period.

For neonatal-onset patients with carbamoyl phosphate synthetase deficiency or ornithine transcarbamylase deficiency who are at least 6 months of age, it is recommended that the daily protein intake be equally divided between natural protein and supplemental essential amino acids. Patients with argininosuccinic acid synthetase deficiency and those with late-onset disease (partial deficiencies, including females heterozygous for ornithine transcarbamylase), initially may receive a diet containing the age-determined minimal daily natural protein allowance.

The protein intake may be increased as tolerated and determined by plasma glutamine and other amino acid levels. However, many patients with partial deficiencies avoid dietary protein. Citrulline supplementation is required and recommended for patients diagnosed with neonatal-onset deficiency of carbamoyl phosphate synthetase or ornithine transcarbamylase; citrulline daily intake is recommended at 0.17 g/kg/day or 3.8 g/m 2 /day.

The free-base form of arginine may be used instead of citrulline in patients with milder forms of carbamoyl phosphate synthetase and ornithine transcarbamylase deficiency (daily intake is recommended at 0.17 g/kg/day or 3.8 g/m 2 /day). Arginine supplementation is needed for patients diagnosed with deficiency of argin…

⛔ Contraindications 15 words ▾

CONTRAINDICATIONS BUPHENYL should not be used to manage acute hyperammonemia, which is a medical emergency.

⚠️ Warnings 164 words ▾

WARNINGS Each BUPHENYL Tablet contains 62 mg of sodium (9.2% w/w) (corresponding to 124 mg of sodium per gram of sodium phenylbutyrate [12.4% w/w]) and BUPHENYL Powder contains 11.7 grams of sodium per 100 grams of powder, corresponding to 125 mg of sodium per gram of sodium phenylbutyrate (12.4% w/w). BUPHENYL 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. Because BUPHENYL is metabolized in the liver and kidney, and phenylacetylglutamine is primarily excreted by the kidney, use caution when administering the drug to patients with hepatic or renal insufficiency or inborn errors of beta oxidation.

Probenecid is known to inhibit the renal transport of many organic compounds, including hippuric acid, and may affect renal excretion of the conjugated product of BUPHENYL as well as its metabolite. Use of corticosteroids may cause the breakdown of body protein and increase plasma ammonia levels.

🤒 Adverse Reactions ~2 min read ▾

ADVERSE REACTIONS The assessment of clinical adverse events came from 206 patients treated with sodium phenylbutyrate. Adverse events (both clinical and laboratory) were not collected systematically in these patients, but were obtained from patient visit reports by the 65 co-investigators. Causality of adverse effects is sometimes difficult to determine in this patient population because they may result from either the underlying disease, the patient's restricted diet, intercurrent illness, or BUPHENYL.

Furthermore, the rates may be underestimated because they were reported primarily by parent or guardian and not the patient. Clinical Adverse Events In female patients, the most common clinical adverse event reported was amenorrhea/menstrual dysfunction (irregular menstrual cycles), which occurred in 23% of the menstruating patients. Decreased appetite occurred in 4% of all patients.

Body odor (probably caused by the metabolite, phenylacetate) and bad taste or taste aversion were each reported in 3% of patients. Other adverse events reported in 2% or fewer patients were: Gastrointestinal : abdominal pain, gastritis, nausea and vomiting; constipation, rectal bleeding, peptic ulcer disease, and pancreatitis each occurred in one patient. Hematologic : aplastic anemia and ecchymoses each occurred in one patient.

Cardiovascular : arrhythmia and edema each occurred in one patient. Renal : renal tubular acidosis Psychiatric : depression Skin : rash Miscellaneous : headache, syncope, and weight gain Neurotoxicity was reported in cancer patients receiving intravenous phenylacetate, 250–300 mg/kg/day for 14 days, repeated at 4-week intervals. Manifestations were predominately somnolence, fatigue, and lightheadedness; with less frequent headache, dysgeusia, hypoacusis, disorientation, impaired memory, and exacerbation of a pre-existing neuropathy.

These adverse events were mainly mild in severity. The acute onset and reversibility when the phenylacetate infusion was discontinued suggest a drug effect. Laboratory Adverse Events In patients with urea cycle disorders, the frequency of laboratory adverse events by body system were: Metabolic : acidosis (14%), alkalosis and hyperchloremia (each 7%), hypophosphatemia (6%), hyperuricemia and hyperphosphatemia (each 2%), and hypernatremia and hypokalemia (each 1%).

Nutritional : hypoalbuminemia (11%) and decreased total protein (3%). Hepatic : increased alkaline phosphatase (6%), increased liver transaminases (4%), and hyperbilirubinemia (1%). Hematologic : anemia (9%), leukopenia and leukocytosis (each 4%), thrombocytopenia (3%), and thrombocytosis (1%).

The clinician is advised to routinely perform urinalysis, blood chemistry profiles, and hematologic tests.

🤰 Pregnancy 44 words ▾

Pregnancy Animal reproduction studies have not been conducted with BUPHENYL. It is also not known whether BUPHENYL can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. BUPHENYL should be given to a pregnant woman only if clearly needed.

🧒 Pediatric Use 25 words ▾

Pediatric Use The use of tablets for neonates, infants and children to the weight of 20 kg is not recommended. (See Dosage and Administration .)

🆘 Overdosage 65 words ▾

OVERDOSAGE Overdoses of BUPHENYL exceeding ten-fold the maximum recommended dosage may produce emesis, CNS depression, metabolic acidosis with or without respiratory alkalosis, hypernatremia, hypokalemia, and hypophosphatemia. Symptoms of overdose overlap with those of acute hyperammonemia. If overdose occurs, discontinue BUPHENYL, monitor plasma phenylacetate and ammonia levels closely, and institute appropriate emergency management, which may include hemodialysis, continuous veno-venous hemofiltration (CVVH), or extracorporeal membrane oxygenation (ECMO).

🧬 Clinical Pharmacology 60 words ▾

CLINICAL PHARMACOLOGY Sodium phenylbutyrate is a pro-drug and is rapidly metabolized to phenylacetate. Phenylacetate is a metabolically active compound that conjugates with glutamine via acetylation to form phenylacetylglutamine. Phenylacetylglutamine then is excreted by the kidneys.

On a molar basis, it is comparable to urea (each containing two moles of nitrogen). Therefore, phenylacetylglutamine provides an alternate vehicle for waste nitrogen excretion.

📦 How Supplied / Storage and Handling 129 words ▾

HOW SUPPLIED BUPHENYL Tablets are available in 250 cc bottles which contain 250 sodium phenylbutyrate tablets (NDC 75987-060-08). The bottles are equipped with child-resistant caps. Each tablet is off-white, oval, and embossed with "UCY 500".

Each tablet contains 500 mg of sodium phenylbutyrate. STORE AT ROOM TEMPERATURE 15°C–30°C (59°F–86°F). AFTER OPENING, KEEP BOTTLE TIGHTLY CLOSED.

BUPHENYL Powder is available in 500 cc bottles, which hold 266 grams of powder, containing 250 grams of sodium phenylbutyrate (NDC 75987-070-09). The bottles are equipped with child-resistant caps. Measurers are provided.

Each level teaspoon (enclosed) dispenses 3.2 grams of powder and 3.0 grams of sodium phenylbutyrate. Each level tablespoon (enclosed) dispenses 9.1 grams of powder and 8.6 grams of sodium phenylbutyrate. STORE AT ROOM TEMPERATURE 15ºC–30ºC (59ºF–86ºF).

AFTER OPENING, KEEP BOTTLE TIGHTLY CLOSED.

📋 Description 135 words ▾

DESCRIPTION BUPHENYL (sodium phenylbutyrate) Tablets for oral administration and BUPHENYL (sodium phenylbutyrate) Powder for oral, nasogastric, or gastrostomy tube administration contain sodium phenylbutyrate. Sodium phenylbutyrate is an off-white crystalline substance which is soluble in water and has a strong salty taste. Sodium phenylbutyrate also is freely soluble in methanol and practically insoluble in acetone and diethyl ether.

It is known chemically as 4-phenylbutyric acid, sodium salt with a molecular weight of 186 and the molecular formula C 10 H 11 O 2 Na. Chemical Structure: Each tablet of BUPHENYL contains 500 mg of sodium phenylbutyrate and the inactive ingredients microcrystalline cellulose NF, magnesium stearate NF, and colloidal silicon dioxide NF. Each gram of BUPHENYL Powder contains 0.94 grams of sodium phenylbutyrate and the inactive ingredients calcium stearate NF, and colloidal silicon dioxide NF.

Chemical Structure

💬 Information for Patients 22 words ▾

Information for Patients The full text of the separate insert of information for patients is reprinted at the end of the labeling.

Glossary — plain-language definitions of medical terms used in this label:

exacerbation: A flare-up or worsening of a condition.

abdominal pain: Pain, cramping, or discomfort felt anywhere in the belly area.

adjunctive therapy: A medicine added alongside a main treatment to help it work better.

adverse event: Any unwanted medical problem that happens during treatment, whether or not the medicine actually caused it.

Adverse Reactions: Unwanted or harmful effects that people experienced while taking a medicine, listed on its official label.

alkaline phosphatase: An enzyme measured in a blood test; higher levels can point to problems with the liver, bile ducts, or bones.

amenorrhea: The absence of monthly menstrual periods.

anemia: A low level of red blood cells or the oxygen-carrying protein inside them, which can cause tiredness, weakness, and paleness.

animal reproduction studies: Tests in pregnant animals used to check whether a medicine might harm a developing baby.

aplastic anemia: A serious condition where the bone marrow stops making enough new blood cells.

arrhythmia: A heartbeat that is too fast, too slow, or irregular instead of steady.

Clinical Pharmacology: The label section explaining how a medicine works in the body and how the body processes it.

CNS depression: A slowing of brain and nervous-system activity that can cause drowsiness, slowed breathing, or reduced alertness.

cognitive impairment: Trouble with thinking, memory, concentration, or judgment.

constipation: Having bowel movements less often than usual, or passing stools that are hard, dry, and difficult to move.

Contraindications: A list of situations or health conditions in which a medicine should not be used because the chance of harm is too high.

depression: A lasting low mood with loss of interest that affects everyday life.

Dosage and Administration: The label section explaining how much of a medicine to use and how to take or give it.

dysgeusia: A changed or unpleasant sense of taste, such as a metallic taste.

edema: Swelling caused by extra fluid trapped in the body's tissues.

efficacy: How well a treatment works under the controlled conditions of a clinical study.

emesis: The medical word for vomiting, or bringing up the contents of the stomach through the mouth.

encephalopathy: Any condition that affects how the brain works, causing confusion, memory problems, or changes in alertness.

Excretion: How the body removes a medicine or its leftover pieces, mainly through the urine or stool.

fetal harm: Injury or damage to a developing baby while it is growing inside the womb.

gastritis: Swelling or irritation of the lining of the stomach.

heart failure: A condition in which the heart cannot pump blood as well as it should, causing tiredness, breathlessness, and swelling.

hemodialysis: A treatment that uses a machine to filter waste and extra fluid from the blood when the kidneys cannot.

hyperbilirubinemia: A higher-than-normal level of bilirubin in the blood, which can cause yellowing of the skin or eyes.

hypernatremia: A higher-than-normal level of sodium (salt) in the blood.

hyperphosphatemia: A higher-than-normal level of phosphate, a mineral, in the blood.

hyperuricemia: A higher-than-normal level of uric acid in the blood, which can lead to gout.

hypokalemia: A lower-than-normal level of potassium, an important mineral, in the blood.

hypophosphatemia: A lower-than-normal level of phosphate, a mineral, in the blood.

incidence: How often a new event, such as a side effect, happens in a group of people over a set period of time.

Indications and Usage: The label section stating which medical conditions the FDA has officially approved the medicine to treat, prevent, or manage.

infusion: Slowly delivering fluid or medicine into a vein over a period of time, usually through a drip.

intravenous: Given directly into a vein through a needle or thin tube; often written as IV.

leukocytosis: A higher-than-normal level of white blood cells, often a sign the body is fighting an infection.

leukopenia: A low level of white blood cells, the cells that help the body fight off infections.

metabolic acidosis: A condition where too much acid builds up in the body's blood and fluids.

metabolite: A new substance formed when the body breaks a medicine down.

NDC: A unique number that identifies a specific medicine, its maker, strength, and package size.

neonatal: Relating to a newborn baby during its first four weeks of life.

Overdosage: The label section describing what can happen if too much of a medicine is taken and how it may be treated.

pancreatitis: Painful swelling of the pancreas, an organ behind the stomach that helps digest food and control blood sugar.

renal excretion: Removal of a medicine from the body through the kidneys into the urine.

somnolence: Feeling very sleepy or drowsy, with trouble staying awake during the day.

syncope: The medical term for fainting, a brief loss of consciousness from a temporary drop in blood flow to the brain.

thrombocytopenia: A low level of platelets, the blood cells that help form clots, which can lead to easier bruising or bleeding.

thrombocytosis: A higher-than-normal level of platelets, the blood cells that help form clots.

tolerance: When the body gets used to a medicine over time, so a larger dose is needed to get the same effect.

transaminases: Liver enzymes measured in a blood test; higher-than-normal levels can be a sign that the liver is irritated or damaged.

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

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Where does this data come from?

Other drugs sharing this product’s First Databank therapeutic class (HIC3). Each links to that NDC’s page in our directory.