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Tetrabenazine 12.5 mg Tablet, Coated, 100-count — NDC 31722-0821-32 package photo

Tetrabenazine 12.5 mg Tablet, Coated, 100-count

by Camber Pharmaceuticals, Inc. · 100 TABLET, COATED in 1 CARTON (31722-821-32)
NDC 31722-0821-32
🏷️ FDA NDC (as labeled) 31722-821-32 billing pads the product segment with a zero
This package
Contains100-count Pack sizes4 compare ↓
Also priced by: Part D plans $10.00/unit — full pricing hub ↓
Also comes in: 10 tablets 31722-0821-31 56 tablets 31722-0821-56 112 tablets 31722-0821-11
Rx only Generic On market Non-controlled
🗂️ Data synced Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

🆔 Identity & classification

FDA NDC (as labeled) 31722-821-32
Product NDC 31722-821
11-digit billing NDC 31722082132
RxCUI 199592, 805464
UNII Z9O08YRN8O
UPC 0331722822114
Application # ANDA204574
SPL Set ID a03c3cf8-fcd4-4dbf-a4f5-59bd7887c902
Established class (EPC) Vesicular Monoamine Transporter 2 Inhibitor
Mechanism of action Vesicular Monoamine Transporter 2 Inhibitors
DEA schedule Non-controlled
Marketing category ANDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2015-08-17
Route ORAL
Dosage form TABLET, COATED
Substance TETRABENAZINE
GPI-14 62380070000310
GPI class Tetrabenazine
GCN Seq No 064582
GCN 15508
HICL code 007350
Ingredient (HICL) Tetrabenazine
HIC1 code H
Therapeutic class — broad (HIC1) Nervous System (Except Autonomic)
HIC2 code H6
Therapeutic class — intermediate (HIC2) Drugs Acting Principally On The Midbrain
HIC3 code H6L
Therapeutic class — specific (HIC3) Drugs To Treat Movement Disorders
AHFS code 28:56.00.00
AHFS class Vesicular Monoamine Transport2 Inhibitor
FDB label name TETRABENAZINE 12.5 MG TABLET
FDB brand name Tetrabenazine
Legend status F — Federal legend — prescription drug or device
TE code (Orange Book) AB · RLD · RS
Why two NDCs? The FDA registers this code as 31722-821-32 — 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 → 31722-0821-32. 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 Vesicular Monoamine Transporter 2 Inhibitor class.

Pharmacologic class Vesicular Monoamine Transporter 2 Inhibitor
Drug family (ATC) Other nervous system drugs
How it works Vesicular Monoamine Transporter 2 Inhibitors
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

LabelerCamber Pharmaceuticals, Inc.
Application holderHETERO LABS LTD UNIT V
FDA applicationANDA204574 (ANDA)
Labeler code31722
First marketedAug 2015
Product typeHuman Prescription Drug
Portfolio603 products on file
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 TETRABENAZINE 12.5 MG TABLET Ingredient Tetrabenazine
📖 What it is MedlinePlus · NLM

Tetrabenazine is used to treat chorea (sudden movements that you cannot control) caused by Huntington's disease (an inherited disease that causes the progressive breakdown of nerve cells in the brain). Tetrabenazine is in a class of medications called vesicular monoamine transporter 2 (VMAT2) inhibitors. It works by changing the activity of certain natural substances in the brain that affect nerves and muscles.

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • Tetrabenazine doesn't treat the disease itself — it specifically targets the involuntary, jerky movements called chorea that are a major symptom of Huntington's disease. By reducin...
  • What exactly does tetrabenazine do for Huntington's disease?
  • It's a very real concern — serious enough that the FDA requires a boxed warning on the label. Tetrabenazine can increase the risk of depression and suicidal thoughts, especially si...
  • I heard this medication can cause depression. How serious is that risk?
📖 Read our full Tetrabenazine guide →
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 / Yellow
ShapeRound
ImprintH;T6
Size7 mm
ScoringScored — splits in 2
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 EWQ57Q8I5X
    Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
  • UNII 7CV7WJK4UI
    Sodium stearyl fumarate is a synthetic compound made from stearyl alcohol and fumaric acid. It acts as a lubricant and glidant in tablets and capsules, helping ingredients flow smoothly during manufacturing and preventing sticking.
  • UNII O8232NY3SJ
    A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.
  • UNII 7SEV7J4R1U
    A powder made from a naturally occurring mineral. In medicines, talc works as a glidant and anti-caking agent, helping tablets and capsules flow smoothly during manufacturing and preventing clumping.

4 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 systemPer eachPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · Q2 2026 $10.00 $999.95 / 100 tablets
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

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Tetrabenazine 12.5 mg 23155-0938-63 Heritage 112 tablets $0.760 AB Availability likely —
Tetrabenazine 12.5 mg 60505-3882-07 Apotex 112 tablets $0.760 AB Availability likely —
Tetrabenazine 12.5 mg 68094-0905-10 Precision 112 tablets $0.760 AB Availability likely —
Tetrabenazine 12.5 mg 69452-0117-21 Bionpharma 112 tablets $0.760 AB Availability likely —
Tetrabenazine 12.5 mg 47335-0277-23 Sun 112 tablets $0.768 — FDA listed —
tetrabenazine 12.5 mg 70436-0101-09 Slate 112 tablets $0.804 AB Availability likely —
tetrabenazine 12.5 mg 68682-0421-12 Oceanside 112 tablets $1.192 AB FDA listed —
Tetrabenazine 12.5 mg 27241-0176-13 Ajanta 112 tablets — — FDA listed —
Tetrabenazine 12.5 mgthis 31722-0821-32 Camber 100 tablets — AB FDA listed —
Tetrabenazine 12.5 mg 43598-0394-05 Dr. 500 tablets — AB FDA listed —
Tetrabenazine 12.5 mg 51407-0480-12 Golden 112 tablets — AB FDA listed —
Xenazine 12.5 mg 67386-0421-01 Lundbeck 112 tablets — AB FDA listed —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
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

🏛️
2015
On the market since
Aug 2015
📍
2026
Currently FDA-listed
11 years listed
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

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 by pack size

Medicaid (SDUD) totals over the four most recent reported quarters for every package size of this drug — handy when a specific package (e.g. a starter/titration pack) carries little or no Medicaid volume on its own.
112 tablets31722-0821-11 13 Rx · $376
10 tablets31722-0821-31 No Medicaid data
100 tablets this page31722-0821-32 No Medicaid data
56 tablets31722-0821-56 No Medicaid data
Drug total (last 4 qtrs): 13 Rx · 333 units · $376 gross reimbursed
Tap a pack size to open its page. Source: CMS State Drug Utilization Data, last 4 quarters.

📊 Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Tetrabenazine — the program that covers self-administered drugs. 9 manufacturers.
⚠️ 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 Tetrabenazine. 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.
Period
Total Part D spend
$8.76M
Claims incl. refills
8.3K
Beneficiaries
3.2K
Spend / beneficiary
$2,706.93
Spend / claim
$1,056.14
Trend by period
💵 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.

📦 Packaging — all sizes for this product

Package NDCDescription Per unit Per pack Marketing startStatus
31722-0821-11 112 TABLET, COATED in 1 BOTTLE (31722-821-11) $0.7604 / ea $85.16 2015-08-17 Active
31722-0821-31 10 TABLET, COATED in 1 BLISTER PACK (31722-821-31) — — 2015-08-17 Active
31722-0821-32 You're viewing this 100 TABLET, COATED in 1 CARTON (31722-821-32) — — 2015-08-17 Active
31722-0821-56 56 TABLET, COATED in 1 BOTTLE (31722-821-56) — — 2015-08-17 Active

You're viewing one of 4 pack sizes for this product.

Pack size FAQ

What quantity is in NDC 31722-0821-32?
NDC 31722-0821-32 is a 100-count package — 100 tablet, coated in 1 carton.
What is the difference between NDC 31722-0821-32 and NDC 31722-0821-31?
Both are Tetrabenazine 12.5 mg Tablet, Coated — the drug itself is identical. NDC 31722-0821-32 is the 100-count package, while NDC 31722-0821-31 is the 10 tablets package.
What NDC number is used to bill for this package of Tetrabenazine 12.5 mg Tablet, Coated?
Bill NDC 31722-0821-32 — the 11-digit billing format is 31722082132. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.

🧭 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 ✓ Available
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) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“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 31722-821-32, 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: 31722-0821-32, written without dashes as 31722082132. 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 31722-0821-32, the first segment (31722) is the labeler code FDA assigned to Camber Pharmaceuticals, Inc.; the middle segment (0821) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (32) 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 Camber Pharmaceuticals, Inc.. Listing status can change — the directory data on this page refreshes weekly.
Does this product come in other package sizes?
Yes — the FDA directory lists 3 other package presentations of this same product, including 10 tablets (31722-0821-31), 56 tablets (31722-0821-56), 112 tablets (31722-0821-11). Each has its own NDC and its own page — see the package list near the top of this page.
Who lists this product with the FDA?
Camber Pharmaceuticals, 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.
🚨 Boxed Warning 🎯 Indications and Usage ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications ⚠️ Warnings and Cautions 🤒 Adverse Reactions 🔄 Drug Interactions 👥 Use in Specific Populations 🤰 Pregnancy 🧒 Pediatric Use 🧓 Geriatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 🧬 Mechanism of Action 📦 How Supplied / Storage and Handling 📋 Description 💬 Information for Patients 💬 Medication Guide
🚨 Boxed Warning ~1 min read ▾

WARNING: DEPRESSION AND SUICIDALITY WARNING: DEPRESSION AND SUICIDALITY Tetrabenazine tablets can increase the risk of depression and suicidal thoughts and behavior (suicidality) in patients with Huntington’s disease. Anyone considering the use of tetrabenazine tablets must balance the risks of depression and suicidality with the clinical need for control of chorea. Close observation of patients for the emergence or worsening of depression, suicidality, or unusual changes in behavior should accompany therapy.

Patients, their caregivers, and families should be informed of the risk of depression and suicidality and should be instructed to report behaviors of concern promptly to the treating physician. Particular caution should be exercised in treating patients with a history of depression or prior suicide attempts or ideation, which are increased in frequency in Huntington’s disease. Tetrabenazine tablets are contraindicated in patients who are actively suicidal, and in patients with untreated or inadequately treated depression [see Contraindications (4), Warnings and Precautions (5.1)].

WARNING: DEPRESSION AND SUICIDALITY See full prescribing information for complete boxed warning. • Increases the risk of depression and suicidal thoughts and behavior (suicidality) in patients with Huntington’s disease (5.1) • Balance risks of depression and suicidality with the clinical need for control of chorea when considering the use of tetrabenazine tablets (5.2) • Monitor patients for the emergence or worsening of depression, suicidality, or unusual changes in behavior (5.1) • Inform patients, caregivers and families of the risk of depression and suicidality and instruct to report behaviors of concern promptly to the treating physician (5.1) • Exercise caution when treating patients with a history of depression or prior suicide attempts or ideation (5.1) • Tetrabenazine tablets are contraindicated in patients who are actively suicidal, and in patients with untreated or inadequately treated depression (4 , 5.1)

🎯 Indications and Usage 38 words ▾

1 INDICATIONS & USAGE Tetrabenazine tablets are indicated for the treatment of chorea associated with Huntington's disease. Tetrabenazine tablet is a vesicular monoamine transporter 2 (VMAT) inhibitor indicated for the treatment of chorea associated with Huntington's disease (1).

⏱️ Dosage and Administration ~3 min read ▾

2 DOSAGE & ADMINISTRATION •Individualization of dose with careful weekly titration is required. The 1st week’s starting dose is 12.5 mg daily; 2nd week, 25 mg (12.5 mg twice daily); then slowly titrate at weekly intervals by 12.5 mg to a tolerated dose that reduces chorea. (2.1 , 2.2) •Doses of 37.5 mg and up to 50 mg per day should be administered in three divided doses per day with a maximum recommended single dose not to exceed 25 mg.

( 2.2) •Patients requiring doses above 50 mg per day should be genotyped for the drug metabolizing enzyme CYP2D6 to determine if the patient is a poor metabolizer (PM) or an extensive metabolizer (EM). (2.2 , 5.3) •Maximum daily dose in PMs: 50 mg with a maximum single dose of 25 mg (2.2) •Maximum daily dose in EMs and intermediate metabolizers (IMs): 100 mg with a maximum single dose of 37.5 mg (2.2) •If serious adverse reactions occur, titration should be stopped and the dose should be reduced. If the adverse reaction(s) do not resolve, consider withdrawal of tetrabenazine tablets.

(2.2) 2.1General Dosing Considerations The chronic daily dose of tetrabenazine tablets used to treat chorea associated with Huntington’s disease (HD) is determined individually for each patient. When first prescribed, tetrabenazine tablets therapy should be titrated slowly over several weeks to identify a dose of tetrabenazine tablets that reduces chorea and is tolerated. Tetrabenazine tablets can be administered without regard to food [see Clinical Pharmacology (12.3)].

2.2Individualization of Dose The dose of tetrabenazine tablets should be individualized. Dosing Recommendations Up to 50 mg per day The starting dose should be 12.5 mg per day given once in the morning. After one week, the dose should be increased to 25 mg per day given as 12.5 mg twice a day.

Tetrabenazine tablets should be titrated up slowly at weekly intervals by 12.5 mg daily, to allow the identification of a tolerated dose that reduces chorea. If a dose of 37.5 to 50 mg per day is needed, it should be given in a three times a day regimen. The maximum recommended single dose is 25 mg.

If adverse reactions such as akathisia, restlessness, parkinsonism, depression, insomnia, anxiety or sedation occur, titration should be stopped and the dose should be reduced. If the adverse reaction does not resolve, consideration should be given to withdrawing tetrabenazine tablets treatment or initiating other specific treatment (e.g., antidepressants) [see Adverse Reactions (6.1)]. Dosing Recommendations Above 50 mg per day Patients who require doses of tetrabenazine tablets greater than 50 mg per day should be first tested and genotyped to determine if they are poor metabolizers (PMs) or extensive metabolizers (EMs) by their ability to express the drug metabolizing enzyme, CYP2D6.

The dose of tetrabenazine tablets should then be individualized accordingly to their status as PMs or EMs [see Warnings and Precautions ( 5.3), Use in Specific Populations (8.7), Clinical Pharmacology (12.3)]. Extensive and Intermediate CYP2D6 Metabolizers Genotyped patients who are identified as extensive (EMs) or intermediate metabolizers (IMs) of CYP2D6, who need doses of tetrabenazine tablets above 50 mg per day, should be titrated up slowly at weekly intervals by 12.5 mg daily, to allow the identification of a tolerated dose that reduces chorea.

Doses above 50 mg per day should be given in a three times a day regimen. The maximum recommended daily dose is 100 mg and the maximum recommended single dose is 37.5 mg. If adverse reactions such as akathisia, parkinsonism, depression, insomnia, anxiety or sedation occur, titration should be stopped and the dose should be reduced.

If the adverse reaction does not resolve, consideration should be given to withdrawing tetrabenazine tablets treatment or initiating other specific treatment (e.g., antidepressants) [see Warnings and Precautions (5.3), Use in Specific Populations (8.7), Clinical Pharmacology (12.3)]. Poor CYP2D6 Metabolizer…

💊 Dosage Forms and Strengths 77 words ▾

3 DOSAGE FORMS & STRENGTHS Tetrabenazine tablets are available in the following strengths and packages: The 12.5 mg tetrabenazine tablets are white to off white, round, flat bevel edged tablets, non-scored, debossed with 'H' on one side and 'T5' on other side. The 25 mg tetrabenazine tablets are yellowish-buff, round, flat bevel edged tablets, scored, debossed with 'H' on one side and 'T6' with score line on other side. •Tablets:12.5 mg non-scored and 25 mg scored (3)

⛔ Contraindications 146 words ▾

4 CONTRAINDICATIONS Tetrabenazine tablets are contraindicated in patients: •Who are actively suicidal, or in patients with untreated or inadequately treated depression [see Warnings and Precautions (5.1)]. •With hepatic impairment [see Use in Specific Populations (8.6), Clinical Pharmacology (12.3)]. •Taking monoamine oxidase inhibitors (MAOIs). Tetrabenazine tablets should not be used in combination with an MAOI, or within a minimum of 14 days of discontinuing therapy with an MAOI. [see Drug Interactions (7.3)]. • Taking reserpine .

At least 20 days should elapse after stopping reserpine before starting tetrabenazine tablets [see Drug Interactions (7.2)]. • Taking deutetrabenazine or valbenazine [see Drug Interactions (7.7)]. • Actively suicidal, or who have depression which is untreated or undertreated (4 , 5.1) • Hepatic impairment ( 4 , 8.6 , 12.3) • Taking monoamine oxidase inhibitors (MAOIs) or reserpine (4 , 7.2 , 7.3) • Taking deutetrabenazine or valbenazine (4 , 7.7)

⚠️ Warnings and Cautions ~3 min read ▾

5 WARNINGS AND PRECAUTIONS • Periodically reevaluate the benefit and potential for adverse effects such as worsening mood, cognition, rigidity, and functional capacity (5.2) • Do not exceed 50 mg/day and the maximum single dose should not exceed 25 mg if administered in conjunction with a strong CYP2D6 inhibitor (e.g., fluoxetine, paroxetine). (5.3 , 7.1) • Neuroleptic Malignant Syndrome (NMS): Discontinue if this occurs. (5.4 , 7.6) • Restlessness, agitation, akathisia and parkinsonism: Reduce dose or discontinue if occurs (5.5 , 5.6) • Sedation/Somnolence: May impair patient’s ability to drive or operate complex machinery (5.7) • QTc prolongation: Not recommended in combination with other drugs that prolong QTc (5.8)

5.1Depression and Suicidality Patients with Huntington’s disease are at increased risk for depression, suicidal ideation or behaviors (suicidality). Tetrabenazine tablets increases the risk for suicidality in patients with HD. All patients treated with tetrabenazine tablets should be observed for new or worsening depression or suicidality.

If depression or suicidality does not resolve, consider discontinuing treatment with tetrabenazine tablets. In a 12-week, double-blind placebo-controlled study in patients with chorea associated with Huntington’s disease, 10 of 54 patients (19%) treated with tetrabenazine tablets were reported to have an adverse event of depression or worsening depression compared to none of the 30 placebo-treated patients. In two open-label studies (in one study, 29 patients received tetrabenazine tablets for up to 48 weeks; in the second study, 75 patients received tetrabenazine tablets for up to 80 weeks), the rate of depression/worsening depression was 35%.

In all of the HD chorea studies of tetrabenazine tablets (n=187), one patient committed suicide, one attempted suicide, and six had suicidal ideation. When considering the use of tetrabenazine tablets, the risk of suicidality should be balanced against the need for treatment of chorea. All patients treated with tetrabenazine tablets should be observed for new or worsening depression or suicidality.

If depression or suicidality does not resolve, consider discontinuing treatment with tetrabenazine tablets. Patients, their caregivers, and families should be informed of the risks of depression, worsening depression, and suicidality associated with tetrabenazine tablets, and should be instructed to report behaviors of concern promptly to the treating physician. Patients with HD who express suicidal ideation should be evaluated immediately.

5.2Clinical Worsening and Adverse Effects Huntington’s disease is a progressive disorder characterized by changes in mood, cognition, chorea, rigidity, and functional capacity over time. In a 12-week controlled trial, tetrabenazine tablets were also shown to cause slight worsening in mood, cognition, rigidity, and functional capacity. Whether these effects persist, resolve, or worsen with continued treatment is unknown.

Prescribers should periodically re-evaluate the need for tetrabenazine tablets in their patients by assessing the effect on chorea and possible adverse effects, including depression and suicidality, cognitive decline, parkinsonism, dysphagia, sedation/somnolence, akathisia, restlessness, and disability. It may be difficult to distinguish between adverse reactions and progression of the underlying disease; decreasing the dose or stopping the drug may help the clinician distinguish between the two possibilities. In some patients, underlying chorea itself may improve over time, decreasing the need for tetrabenazine tablets.

5.3Laboratory Tests Before prescribing a daily dose of tetrabenazine tablets that is greater than 50 mg per day, patients should be genotyped to determine if they express the drug metabolizing enzyme, CYP2D6. CYP2D6 testing is necessary to determine whether patients are poor metabolizers (PMs), extensive (EMs) or intermediate metabolizers (IMs) of tetrabenazine tablets. P…

🤒 Adverse Reactions ~3 min read ▾

6 ADVERSE REACTIONS The following serious adverse reactions are described below and elsewhere in the labeling: • Depression and Suicidality [see Warnings and Precautions (5.1)] • Neuroleptic Malignant Syndrome (NMS) [see Warnings and Precautions (5.4)] • Akathisia, Restlessness, and Agitation [see Warnings and Precautions (5.5)] • Parkinsonism [see Warnings and Precautions (5.6)] • Sedation and Somnolence [see Warnings and Precautions (5.7)] • QTc Prolongation [see Warnings and Precautions (5.8)] • Hypotension and Orthostatic Hypotension [see Warnings and Precautions (5.9)] • Hyperprolactinemia [see Warnings and Precautions (5.10)] • Binding to Melanin-Containing Tissues [see Warnings and Precautions (5.11)] Most common adverse reactions (>10% and at least 5% greater than placebo) were: Sedation/somnolence, fatigue, insomnia, depression, akathisia, anxiety/anxiety aggravated, nausea (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Hetero Labs Limited at 866-495-1995 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. During its development, tetrabenazine tablets were administered to 773 unique subjects and patients. The conditions and duration of exposure to tetrabenazine tablets varied greatly, and included single-dose and multiple-dose clinical pharmacology studies in healthy volunteers (n=259) and open-label (n=529) and double-blind studies (n=84) in patients.

In a randomized, 12-week, placebo-controlled clinical trial of HD patients, adverse reactions were more common in the tetrabenazine group than in the placebo group. Forty-nine of 54 (91%) patients who received tetrabenazine tablets experienced one or more adverse reactions at any time during the study. The most common adverse reactions (over 10%, and at least 5% greater than placebo) were sedation/somnolence, fatigue, insomnia, depression, akathisia, anxiety/anxiety aggravated, and nausea.

Adverse Reactions Occurring in ≥4% of Patients The number and percentage of the most common adverse reactions that occurred at any time during the study in ≥4% of tetrabenazine-treated patients, and with a greater frequency than in placebo-treated patients, are presented in Table 1. Table 1: Adverse Reactions in a 12-Week, Double-Blind, Placebo-Controlled Trial in Patients with Huntington’s Disease Adverse Reaction Tetrabenazine Tablets n = 54 (%) Placebo n = 30 (%) Sedation/somnolence 31 3 Insomnia 22 0 Fatigue 22 13 Depression 19 0 Akathisia 19 0 Anxiety/anxiety aggravated 15 3 Fall 15 13 Nausea 13 7 Upper respiratory tract infection 11 7 Irritability 9 3 Balance difficulty 9 0 Parkinsonism/bradykinesia 9 0 Vomiting 6 3 Laceration (head) 6 0 Ecchymosis 6 0 Decreased appetite 4 0 Obsessive reaction 4 0 Dizziness 4 0 Dysarthria 4 0 Unsteady gait 4 0 Headache 4 3 Shortness of breath 4 0 Bronchitis 4 0 Dysuria 4 0 Dose escalation was discontinued or dosage of study drug was reduced because of one or more adverse reactions in 28 of 54 (52%) patients randomized to tetrabenazine tablets.

These adverse reactions consisted of sedation (15), akathisia (7), parkinsonism (4), depression (3), anxiety (2), fatigue (1) and diarrhea (1). Some patients had more than one AR and are, therefore, counted more than once. Adverse Reactions Due to Extrapyramidal Symptoms Table 2 describes the incidence of events considered to be extrapyramidal adverse reactions which occurred at a greater frequency in tetrabenazine-treated patients compared to placebo-treated patients.

Table 2: Adverse Reactions Due to Extrapyramidal Symptoms in a 12-Week, Double-Blind, Placebo-Controlled Trial in Patients with Huntington’s Disease Tetrabenazine Tablets n = 54 % Placebo n = 30 % Akathisia* 19 0 Extrapyramidal event † 15 0 Any extr…

🔄 Drug Interactions ~2 min read ▾

7 DRUG INTERACTIONS 7.1Strong CYP2D6 Inhibitors In vitro studies indicate that α-HTBZ and β-HTBZ are substrates for CYP2D6. Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine, quinidine) markedly increase exposure to these metabolites. A reduction in tetrabenazine tablets dose may be necessary when adding a strong CYP2D6 inhibitor (e.g., fluoxetine, paroxetine, quinidine) in patients maintained on a stable dose of tetrabenazine tablets.

The daily dose of tetrabenazine tablets should not exceed 50 mg per day and the maximum single dose of tetrabenazine tablets should not exceed 25 mg in patients taking strong CYP2D6 inhibitors. [see Dosage and Administration (2.3), Warnings and Precautions (5.3), Use in Specific Populations ( 8.7), Clinical Pharmacology (12.3)]. 7.2Reserpine Reserpine binds irreversibly to VMAT2, and the duration of its effect is several days. Prescribers should wait for chorea to re-emerge before administering tetrabenazine tablets to avoid overdosage and major depletion of serotonin and norepinephrine in the CNS.

At least 20 days should elapse after stopping reserpine before starting tetrabenazine tablets. Tetrabenazine tablets and reserpine should not be used concomitantly [see Contraindications (4)]. 7.3Monoamine Oxidase Inhibitors (MAOIs) Tetrabenazine tablets are contraindicated in patients taking MAOIs.

Tetrabenazine tablets should not be used in combination with an MAOI, or within a minimum of 14 days of discontinuing therapy with an MAOI. [see Contraindications ( 4)].

7.4Alcohol or Other Sedating Drugs Concomitant use of alcohol or other sedating drugs may have additive effects and worsen sedation and somnolence [see Warnings and Precautions (5.7)]. 7.5Drugs That Cause QTc Prolongation Tetrabenazine tablets causes a small prolongation of QTc (about 8 msec), concomitant use with other drugs that are known to cause QTc prolongation should be avoided, these including antipsychotic medications (e.g., chlorpromazine, haloperidol, thioridazine, ziprasidone), antibiotics (e.g., moxifloxacin), Class 1A (e.g., quinidine, procainamide), and Class III (e.g., amiodarone, sotalol) antiarrhythmic medications or any other medications known to prolong the QTc interval.

Tetrabenazine tablets should be avoided in patients with congenital long QT syndrome, and in patients with a history of cardiac arrhythmias. Certain conditions may increase the risk for torsade de pointes or sudden death such as (1) bradycardia; (2) hypokalemia or hypomagnesemia; (3) concomitant use of other drugs that prolong the QTc interval; and (4) presence of congenital prolongation of the QT interval [see Warnings and Precautions (5.8), Clinical Pharmacology (12.2)]. 7.6Neuroleptic Drugs The risk for Parkinsonism, NMS, and akathisia may be increased by concomitant use of tetrabenazine and dopamine antagonists or antipsychotics (e.g., chlorpromazine, haloperidol, olanzapine, risperidone, thioridazine, ziprasidone) [see Warnings and Precautions (5.4 , 5.5 , 5.6)].

7.7Concomitant Deutetrabenazine or Valbenazine Tetrabenazine tablets are contraindicated in patients currently taking deutetrabenazine or valbenazine.

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS Pregnancy: Based on animal data, may cause fetal harm. (8.1) See 17 for PATIENT COUNSELING INFORMATION and Medication Guide Revised: 01/2018

8.1Pregnancy Teratogenic Effects: Risk Summary There are no adequate data on the developmental risk associated with the use of tetrabenazine in pregnant women. Administration of tetrabenazine to rats throughout pregnancy and lactation resulted in an increase in stillbirths and postnatal offspring mortality. Administration of a major human metabolite of tetrabenazine to rats during pregnancy or during pregnancy and lactation produced adverse effects on the developing fetus and offspring (increased mortality, decreased growth, and neurobehavioral and reproductive impairment).

The adverse developmental effects of tetrabenazine and a major human metabolite of tetrabenazine in rats occurred at clinically relevant doses [see Data]. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown.

Data Animal Data Tetrabenazine had no clear effects on embryofetal development when administered to pregnant rats throughout the period of organogenesis at oral doses up to 30 mg/kg/day (or 3 times the maximum recommended human dose [MRHD] of 100 mg/day on a mg/m 2 basis). Tetrabenazine had no effects on embryofetal development when administered to pregnant rabbits during the period of organogenesis at oral doses up to 60 mg/kg/day (or 12 times the MRHD on a mg/m 2 basis). When tetrabenazine (5, 15, and 30 mg/kg/day) was orally administered to pregnant rats from the beginning of organogenesis through the lactation period, an increase in stillbirths and offspring postnatal mortality was observed at 15 and 30 mg/kg/day and delayed pup maturation was observed at all doses.

A no-effect dose for pre-and postnatal developmental toxicity in rats was not identified. The lowest dose tested (5 mg/kg/day) was less than the MRHD on a mg/m 2 basis. Because rats dosed orally with tetrabenazine do not produce 9-desmethyl-β-DHTBZ, a major human metabolite of tetrabenazine, the metabolite was directly administered to pregnant and lactating rats.

Oral administration of 9-desmethyl-β-DHTBZ (8, 15, and 40 mg/kg/day) throughout the period of organogenesis produced increases in embryofetal mortality at 15 and 40 mg/kg/day and reductions in fetal body weights at 40 mg/kg/day, which was also maternally toxic. When 9-desmethyl-β-DHTBZ (8, 15, and 40 mg/kg/day) was orally administered to pregnant rats from the beginning of organogenesis through the lactation period, increases in gestation duration, stillbirths, and offspring postnatal mortality (40 mg/kg/day); decreases in pup weights (40 mg/kg/day); and neurobehavioral (increased activity, learning and memory deficits) and reproductive (decreased litter size) impairment (15 and 40 mg/kg/day) were observed.

Maternal toxicity was seen at the highest dose. The no-effect dose for developmental toxicity in rats (8 mg/kg/day) was associated with plasma exposures (AUC) of 9-desmethyl-β-DHTBZ in pregnant rats lower than that in humans at the MRHD.

8.2Lactation Risk Summary There are no data on the presence of tetrabenazine or its metabolites in human milk, the effects on the breastfed infant, or the effects of the drug on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for tetrabenazine and any potential adverse effects on the breastfed infant from tetrabenazine or from the underlying maternal condition.

8.4Pediatric Use Safety and effectiveness in pediatric patients have not been established.

8.5Geriatric Use The pharmacokinetics of tetrabenazine tablets and its primary metabolites have not been formally studied in geriatric subjects. 8.6Hepatic Impairment Beca…

🤰 Pregnancy ~2 min read ▾

8.1Pregnancy Teratogenic Effects: Risk Summary There are no adequate data on the developmental risk associated with the use of tetrabenazine in pregnant women. Administration of tetrabenazine to rats throughout pregnancy and lactation resulted in an increase in stillbirths and postnatal offspring mortality. Administration of a major human metabolite of tetrabenazine to rats during pregnancy or during pregnancy and lactation produced adverse effects on the developing fetus and offspring (increased mortality, decreased growth, and neurobehavioral and reproductive impairment).

The adverse developmental effects of tetrabenazine and a major human metabolite of tetrabenazine in rats occurred at clinically relevant doses [see Data]. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown.

Data Animal Data Tetrabenazine had no clear effects on embryofetal development when administered to pregnant rats throughout the period of organogenesis at oral doses up to 30 mg/kg/day (or 3 times the maximum recommended human dose [MRHD] of 100 mg/day on a mg/m 2 basis). Tetrabenazine had no effects on embryofetal development when administered to pregnant rabbits during the period of organogenesis at oral doses up to 60 mg/kg/day (or 12 times the MRHD on a mg/m 2 basis). When tetrabenazine (5, 15, and 30 mg/kg/day) was orally administered to pregnant rats from the beginning of organogenesis through the lactation period, an increase in stillbirths and offspring postnatal mortality was observed at 15 and 30 mg/kg/day and delayed pup maturation was observed at all doses.

A no-effect dose for pre-and postnatal developmental toxicity in rats was not identified. The lowest dose tested (5 mg/kg/day) was less than the MRHD on a mg/m 2 basis. Because rats dosed orally with tetrabenazine do not produce 9-desmethyl-β-DHTBZ, a major human metabolite of tetrabenazine, the metabolite was directly administered to pregnant and lactating rats.

Oral administration of 9-desmethyl-β-DHTBZ (8, 15, and 40 mg/kg/day) throughout the period of organogenesis produced increases in embryofetal mortality at 15 and 40 mg/kg/day and reductions in fetal body weights at 40 mg/kg/day, which was also maternally toxic. When 9-desmethyl-β-DHTBZ (8, 15, and 40 mg/kg/day) was orally administered to pregnant rats from the beginning of organogenesis through the lactation period, increases in gestation duration, stillbirths, and offspring postnatal mortality (40 mg/kg/day); decreases in pup weights (40 mg/kg/day); and neurobehavioral (increased activity, learning and memory deficits) and reproductive (decreased litter size) impairment (15 and 40 mg/kg/day) were observed.

Maternal toxicity was seen at the highest dose. The no-effect dose for developmental toxicity in rats (8 mg/kg/day) was associated with plasma exposures (AUC) of 9-desmethyl-β-DHTBZ in pregnant rats lower than that in humans at the MRHD.

🧒 Pediatric Use 13 words ▾

8.4Pediatric Use Safety and effectiveness in pediatric patients have not been established.

🧓 Geriatric Use 20 words ▾

8.5Geriatric Use The pharmacokinetics of tetrabenazine tablets and its primary metabolites have not been formally studied in geriatric subjects.

🆘 Overdosage 128 words ▾

10 OVERDOSAGE Three episodes of overdose occurred in the open-label trials performed in support of registration. Eight cases of overdose with tetrabenazine tablets have been reported in the literature. The dose of tetrabenazine tablets in these patients ranged from 100 mg to 1 g.

Adverse reactions associated with tetrabenazine tablets overdose include acute dystonia, oculogyric crisis, nausea and vomiting, sweating, sedation, hypotension, confusion, diarrhea, hallucinations, rubor, and tremor. Treatment should consist of those general measures employed in the management of overdosage with any CNS-active drug. General supportive and symptomatic measures are recommended.

Cardiac rhythm and vital signs should be monitored. In managing overdosage, the possibility of multiple drug involvement should always be considered. The physician should consider contacting a poison control center on the treatment of any overdose.

🧬 Clinical Pharmacology ~3 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action The precise mechanism by which tetrabenazine tablets exerts its anti-chorea effects is unknown but is believed to be related to its effect as a reversible depletor of monoamines (such as dopamine, serotonin, norepinephrine, and histamine) from nerve terminals. Tetrabenazine reversibly inhibits the human vesicular monoamine transporter type 2 (VMAT2) (Ki ≈ 100 nM), resulting in decreased uptake of monoamines into synaptic vesicles and depletion of monoamine stores. Human VMAT2 is also inhibited by dihydrotetrabenazine (HTBZ), a mixture of α-HTBZ and β-HTBZ. α- and β-HTBZ, major circulating metabolites in humans, exhibit high in vitro binding affinity to bovine VMAT2.

Tetrabenazine exhibits weak in vitro binding affinity at the dopamine D2 receptor (Ki = 2100 nM).

12.2Pharmacodynamics QTc Prolongation The effect of a single 25 or 50 mg dose of tetrabenazine tablets on the QT interval was studied in a randomized, double-blind, placebo controlled crossover study in healthy male and female subjects with moxifloxacin as a positive control. At 50 mg, tetrabenazine tablets caused an approximately 8 msec mean increase in QTc (90% CI: 5.0, 10.4 msec). Additional data suggest that inhibition of CYP2D6 in healthy subjects given a single 50 mg dose of tetrabenazine tablets does not further increase the effect on the QTc interval.

Effects at higher exposures to either tetrabenazine tablets or its metabolites have not been evaluated [see Warnings and Precautions (5.8), Drug Interactions (7.5)]. Melanin Binding Tetrabenazine or its metabolites bind to melanin-containing tissues (i.e., eye, skin, fur) in pigmented rats. After a single oral dose of radiolabeled tetrabenazine, radioactivity was still detected in eye and fur at 21 days post dosing [see Warnings and Precautions (5.11)].

12.3Pharmacokinetics Absorption Following oral administration of tetrabenazine, the extent of absorption is at least 75%. After single oral doses ranging from 12.5 to 50 mg, plasma concentrations of tetrabenazine are generally below the limit of detection because of the rapid and extensive hepatic metabolism of tetrabenazine by carbonyl reductase to the active metabolites α-HTBZ and β-HTBZ. α-HTBZ and β-HTBZ are metabolized principally by CYP2D6. Peak plasma concentrations (C max ) of α-HTBZ and β-HTBZ are reached within 1 to 1½ hours post-dosing. α-HTBZ is subsequently metabolized to a minor metabolite, 9-desmethyl-α-DHTBZ. β-HTBZ is subsequently, metabolized to another major circulating metabolite, 9-desmethyl-β-DHTBZ, for which C max is reached approximately 2 hours post-dosing.

Food Effects The effects of food on the bioavailability of tetrabenazine tablets were studied in subjects administered a single dose with and without food. Food had no effect on mean plasma concentrations, C max , or the area under the concentration time course (AUC) of α-HTBZ or β-HTBZ [see Dosage and Administration ( 2.1)]. Distribution Results of PET-scan studies in humans show that radioactivity is rapidly distributed to the brain following intravenous injection of 11 C-labeled tetrabenazine or α-HTBZ, with the highest binding in the striatum and lowest binding in the cortex.

The in vitro protein binding of tetrabenazine, α-HTBZ, and β-HTBZ was examined in human plasma for concentrations ranging from 50 to 200 ng/mL. Tetrabenazine binding ranged from 82% to 85%, α-HTBZ binding ranged from 60% to 68%, and β-HTBZ binding ranged from 59% to 63%. Metabolism After oral administration in humans, at least 19 metabolites of tetrabenazine have been identified. α-HTBZ, β-HTBZ and 9-desmethyl-β-DHTBZ, are the major circulating metabolites and are, subsequently, metabolized to sulfate or glucuronide conjugates. α-HTBZ and β-HTBZ are formed by carbonyl reductase that occurs mainly in the liver. α-HTBZ is O-dealkylated by CYP450 enzymes, principally CYP2D6, with some contribution of CYP1A2 to form 9-desmethyl-α-DHTBZ, a minor metabolite. β-HTBZ i…

🧬 Mechanism of Action 118 words ▾

12.1Mechanism of Action The precise mechanism by which tetrabenazine tablets exerts its anti-chorea effects is unknown but is believed to be related to its effect as a reversible depletor of monoamines (such as dopamine, serotonin, norepinephrine, and histamine) from nerve terminals. Tetrabenazine reversibly inhibits the human vesicular monoamine transporter type 2 (VMAT2) (Ki ≈ 100 nM), resulting in decreased uptake of monoamines into synaptic vesicles and depletion of monoamine stores. Human VMAT2 is also inhibited by dihydrotetrabenazine (HTBZ), a mixture of α-HTBZ and β-HTBZ. α- and β-HTBZ, major circulating metabolites in humans, exhibit high in vitro binding affinity to bovine VMAT2.

Tetrabenazine exhibits weak in vitro binding affinity at the dopamine D2 receptor (Ki = 2100 nM).

📦 How Supplied / Storage and Handling 140 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING 16.1How Supplied Tetrabenazine tablets are available in the following strengths and packages: The 12.5 mg tetrabenazine tablets are white to off white, round, flat bevel edged tablets, non-scored, debossed with 'H' on one side and 'T5' on other side. They are supplied as follows: Bottles of 56 tablets (NDC 31722-821-56) Bottles of 112 tablets (NDC 31722-821-11) Blister pack of 100 (10x10) unit dose tablets (NDC 31722-821-32) The 25 mg tetrabenazine tablets are yellowish-buff, round, flat bevel edged tablets, scored, debossed with 'H' on one side and 'T6' with score line on other side.

They are supplied as follows: Bottles of 56 tablets (NDC 31722-822-56) Bottles of 112 tablets (NDC 31722-822-11) Blister pack of 100 (10x10) unit dose tablets (NDC 31722-822-32) 16.2Storage Store at 20º to 25ºC (68º to 77º F). [see USP Controlled Room Temperature].

📋 Description 151 words ▾

11 DESCRIPTION Tetrabenazine tablet is a monoamine depletor for oral administration. The molecular weight of tetrabenazine is 317.42. Tetrabenazine is a hexahydro-dimethoxybenzoquinolizine derivative and has the following chemical name: 1,3,4,6,7,11b-Hexahydro-9,10-dimethoxy-3-(2-methylpropyl)-2H-benzo[a]quinolizin-2-one.

The empirical formula C 19 H 27 NO 3 is represented by the following structural formula: Tetrabenazine is off-white to pale yellow powder that is soluble in chloroform and sparingly soluble in methanol. Each tetrabenazine tablet contains either 12.5 or 25 mg of tetrabenazine as the active ingredient. Tetrabenazine tablets contain tetrabenazine as the active ingredient and the following inactive ingredients: lactose monohydrate, pregelatinized starch, sodium stearyl fumarate and talc.

The 25 mg strength tablet also contains ferric oxide yellow as an inactive ingredient. The botanical source for pregelatinized starch is corn starch. Tetrabenazine tablets are supplied as yellowish-buff scored tablet containing 25 mg of tetrabenazine or as a white to off white non-scored tablet containing 12.5 mg of tetrabenazine.

DESCRIPTION

💬 Information for Patients ~2 min read ▾

17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Medication Guide). Risk of Suicidality Inform patients and their families that tetrabenazine tablets may increase the risk of suicidal thinking and behaviors. Counsel patients and their families to remain alert to the emergence of suicidal ideation and to report it immediately to the patient’s physician [see Contraindications (4), Warnings and Precautions ( 5.1)].

Risk of Depression Inform patients and their families that tetrabenazine tablets may cause depression or may worsen pre-existing depression. Encourage patients and their families to be alert to the emergence of sadness, worsening of depression, withdrawal, insomnia, irritability, hostility (aggressiveness), akathisia (psychomotor restlessness), anxiety, agitation, or panic attacks and to report such symptoms promptly to the patient’s physician [see Contraindications (4), Warnings and Precautions (5.1)]. Dosing of Tetrabenazine Tablets Inform patients and their families that the dose of tetrabenazine tablets will be increased slowly to the dose that is best for each patient.

Sedation, akathisia, parkinsonism, depression, and difficulty swallowing may occur. Such symptoms should be promptly reported to the physician, and the tetrabenazine tablets dose may need to be reduced or discontinued [ see Dosage and Administration (2.2)]. Risk of Sedation and Somnolence Inform patients that tetrabenazine tablets may induce sedation and somnolence and may impair the ability to perform tasks that require complex motor and mental skills.

Advise patients that until they learn how they respond to tetrabenazine tablets, they should be careful doing activities that require them to be alert, such as driving a car or operating machinery [see Warnings and Precautions (5.7)]. Interaction with Alcohol Advise patients and their families that alcohol may potentiate the sedation induced by tetrabenazine tablets [see Drug Interactions ( 7.4)]. Usage in Pregnancy Advise patients and their families to notify the physician if the patient becomes pregnant or intends to become pregnant during tetrabenazine therapy, or is breast-feeding or intending to breast-feed an infant during therapy [see Use in Specific Populations (8.1)].

Manufactured for: Camber Pharmaceuticals, Inc. Piscataway, NJ 08854. Manufactured by: HETERO TM HETERO LABS LIMITED Unit V, Polepally, Jadcherla, Mahabubnagar-509 301, India.

Revised: January 2018 Fig3

💬 Medication Guide ~3 min read ▾

MEDICATION GUIDE Tetrabenazine Tablets (teh-trah-BEN-ah-zeen) Read the Medication Guide that comes with tetrabenazine tablets before you start taking it and each time you refill the prescription. There may be new information. This information does not take the place of talking with your doctor about your medical condition or your treatment.

You should share this information with your family members and caregivers. What is the most important information I should know about tetrabenazine tablets? •Tetrabenazine tablets can cause serious side effects, including: o depression o suicidal thoughts o suicidal actions •You should not start taking tetrabenazine tablets if you are depressed (have untreated depression or depression that is not well controlled by medicine) or have suicidal thoughts. •Pay close attention to any changes, especially sudden changes, in mood, behaviors, thoughts or feelings.

This is especially important when tetrabenazine tablets are started and when the dose is changed. Call the doctor right away if you become depressed or have any of the following symptoms, especially if they are new, worse, or worry you: •feel sad or have crying spells •lose interest in seeing your friends or doing things you used to enjoy •sleep a lot more or a lot less than usual •feel unimportant •feel guilty •feel hopeless or helpless •more irritable, angry or aggressive than usual •more or less hungry than usual or notice a big change in your body weight •have trouble paying attention •feel tired or sleepy all the time •have thoughts about hurting yourself or ending your life What are tetrabenazine tablets?

Tetrabenazine tablets are a medicine that is used to treat the involuntary movements (chorea) of Huntington’s disease. A Tetrabenazine tablet does not cure the cause of the involuntary movements, and it does not treat other symptoms of Huntington’s disease, such as problems with thinking or emotions. It is not known whether tetrabenazine tablets are safe and effective in children.

Who should not take tetrabenazine tablets? Do not take tetrabenazine tablets if you: •are depressed or have thoughts of suicide. See “What is the most important information I should know about tetrabenazine tablets?” •have liver problems. •are taking a monoamine oxidase inhibitor (MAOI) medicine.

Ask your doctor or pharmacist if you are not sure. •are taking reserpine. Do not take medicines that contain reserpine (such as Serpalan® and Renese®-R) with tetrabenazine tablets. If your doctor plans to switch you from taking reserpine to tetrabenazine tablets, you must wait at least 20 days after your last dose of reserpine before you start taking tetrabenazine tablets.

What should I tell my doctor before taking tetrabenazine tablets? Tell your doctor about all your medical conditions, including if you: •have emotional or mental problems (for example, depression, nervousness, anxiety, anger, agitation, psychosis, previous suicidal thoughts or suicide attempts). •have liver disease. •have any allergies. See the end of this Medication Guide for a complete list of the ingredients in tetrabenazine tablets. •have breast cancer or a history of breast cancer. •have heart disease that is not stable, have heart failure or recently had a heart attack. •have an irregular heart beat (cardiac arrhythmia). •are pregnant or plan to become pregnant.

It is not known if tetrabenazine tablets can harm your unborn baby •are breast-feeding. It is not known if tetrabenazine passes into breast milk. Tell your doctor about all the medicines you take, including prescription medicines and nonprescription medicines, vitamins and herbal products.

Using tetrabenazine tablets with certain other medicines may cause serious side effects. Do not start any new medicines while taking tetrabenazine tablets without talking to your doctor first. How should I take tetrabenazine tablets? •Tetrabenazine is a tablet that you take by mouth. • Take tetrabenazine tablets exactly as prescribed by your doct…

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
← 31722-0820-01 · Camber 31722-0822-11 · Camber →
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.