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Synthroid Levothyroxine Sodium 25 ug Tablet, 14-count — NDC 00074-4341-72 package photo

Synthroid Levothyroxine Sodium 25 ug Tablet, 14-count

by AbbVie Inc. · 2 BLISTER PACK in 1 CARTON (0074-4341-72) / 7 TABLET in 1 BLISTER PACK
NDC 00074-4341-72
🏷️ FDA NDC (as labeled) 0074-4341-72 billing pads the labeler segment with a zero
This package
Contains14-count Pack sizes3 compare ↓
Also priced by: Part D plans $1.67/unit — full pricing hub ↓
Also comes in: 90 tablets 00074-4341-90 1000 tablets 00074-4341-19
Rx only Brand 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

🚨
Active recall for this product.
Class III · Oct 17, 2023 — Labeling: Wrong Barcode- One (1) of every forty (40) unit dose blister will contain incorrect barcode information that causes a 125mcg unit dose is scanned as 200mcg unit dose. (AbbVie Inc.) · FDA recall D-0088-2024
Check your lot/expiration against the official notice — look up the recall number in the FDA recall database ↗
⚠️
Other active recalls for Levothyroxine Sodium (different manufacturers) — 6 · tap to view
These affect other manufacturers’ products for the same ingredient — not necessarily the exact NDC on this page.
Class II · Aug 6, 2026 — Subpotent Drug (ACCORD HEALTHCARE, INC.) · FDA recall D-0781-2026
Class II · Aug 6, 2026 — Subpotent Drug (ACCORD HEALTHCARE, INC.) · FDA recall D-0786-2026
Class II · Aug 6, 2026 — Subpotent Drug (ACCORD HEALTHCARE, INC.) · FDA recall D-0782-2026
Class II · Aug 6, 2026 — Subpotent Drug (ACCORD HEALTHCARE, INC.) · FDA recall D-0775-2026
Class II · Aug 6, 2026 — Subpotent Drug (ACCORD HEALTHCARE, INC.) · FDA recall D-0777-2026
Class II · Aug 6, 2026 — Subpotent Drug (ACCORD HEALTHCARE, INC.) · FDA recall D-0776-2026
Each entry is an official FDA enforcement report — look up any recall number in the FDA recall database ↗

🆔 Identity & classification

FDA NDC (as labeled) 0074-4341-72
Product NDC 0074-4341
11-digit billing NDC 00074434172
RxCUI 892246, 892251, 892255, 966158, 966171, 966185, 966191, 966201,
UNII 9J765S329G
UPC 0300747149902, 0300747068197, 0300744341194, 0300745182192 +6 more
Application # NDA021402
SPL Set ID 1e11ad30-1041-4520-10b0-8f9d30d30fcc
Established class (EPC) l-Thyroxine
Chemical class Thyroxine
DEA schedule Non-controlled
Marketing category NDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2002-07-24
Route ORAL
Dosage form TABLET
Substance LEVOTHYROXINE SODIUM
GPI-14 28100010100305
GPI class Synthroid
GCN Seq No 006648
GCN 26321
HICL code 002849
Ingredient (HICL) Levothyroxine Sodium
HIC1 code P
Therapeutic class — broad (HIC1) Endocrine System
HIC2 code P3
Therapeutic class — intermediate (HIC2) Drugs Affecting Thyroid Function
HIC3 code P3A
Therapeutic class — specific (HIC3) Thyroid Hormones
AHFS code 68:36.04.00
AHFS class Thyroid Agents
FDB label name SYNTHROID 25 MCG TABLET
FDB brand name Synthroid
Legend status F — Federal legend — prescription drug or device
TE code (Orange Book) AB1,AB2 · RLD · RS
Why two NDCs? The FDA registers this code as 0074-4341-72 — a 4-4-2 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 labeler segment → 00074-4341-72. 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 l-Thyroxine class.

Pharmacologic class l-Thyroxine
Drug family (ATC) Thyroid hormones
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

LabelerAbbVie Inc.
Application holderABBVIE INC
FDA applicationNDA021402 (NDA)
Labeler code00074
First marketedJul 2002
Product typeHuman Prescription Drug
Portfolio128 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 SYNTHROID 25 MCG TABLET Ingredient Levothyroxine Sodium
📗 Our plain-language guide HelloPharmacist
  • Your thyroid gland isn't making enough of a hormone called T4, which your whole body depends on to regulate your energy, metabolism, heart rate, and more. Levothyroxine is a precis...
  • What exactly is levothyroxine doing for me — why do I need to take it every day?
  • Timing really does make a difference with this medication. Food — especially high-fiber foods or anything soy-based — can block your gut from absorbing it properly. Taking it 30 to...
  • Why does it matter so much when I take it — can't I just take it with breakfast?
📖 Read our full Levothyroxine 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 orange / white / purple / green / yellow / red / brown / blue / pink
ShapeRound
ImprintSYNTHROID;300
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 5C5403N26O
    Acacia is a natural gum derived from acacia tree sap. It serves as a binder, thickener, and emulsifier to help hold ingredients together, improve texture, and stabilize the medicine.
  • UNII H77VEI93A8
    A synthetic yellow dye used to color medications. It helps identify the drug and make it visually distinctive, with no effect on how the medicine works.
  • 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 70097M6I30
    Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
  • UNII FZ989GH94E
    Povidone is a synthetic polymer made from a plastic-like material. It acts as a binder to hold tablet ingredients together and as a disintegrant to help the tablet break apart in your stomach so the medicine can be absorbed.
  • UNII C151H8M554
    A natural sugar derived from sugar cane or sugar beets. It's used as a sweetener, filler, and binder to improve taste, add bulk, and help hold tablet or capsule ingredients together.
  • 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.

7 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 $1.67 $23.44 / 14 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
Levothyroxine Sodium 25 ug 00378-1800-10 Mylan 1000 tablets $0.036 AB1,AB2,AB3,AB4 Availability likely —
Levothyroxine Sodium 25 ug 00527-3280-43 Lannett 1000 tablets $0.036 AB1,AB2,AB3 Availability likely —
Levothyroxine Sodium .025 mg 00904-6949-61 Major 100 tablets $0.036 AB1,AB2,AB3 Availability likely —
Levothyroxine sodium 25 ug 16729-0447-15 Accord 90 tablets $0.036 AB1,AB2,AB3,AB4 Availability likely —
Levothyroxine Sodium 25 ug 33342-0393-10 Macleods 90 tablets $0.036 AB1,AB2,AB3,AB4 Availability likely —
levothyroxine sodium 25 ug 47781-0640-10 Alvogen, 1000 tablets $0.036 AB1,AB2,AB3,AB4 Availability likely —
Levothyroxine Sodium 25 ug 51079-0444-20 Mylan 100 tablets $0.036 AB1,AB2,AB3,AB4 Availability likely —
Levothyroxine Sodium .025 mg 60687-0453-01 American 100 tablets $0.036 AB1,AB2,AB3 Availability likely —
Levothyroxine Sodium .025 mg 68180-0965-01 Lupin 100 tablets $0.036 AB1,AB2,AB3 Availability likely —
Levothyroxine Sodium .025 mg 69238-1830-01 Amneal 100 tablets $0.036 AB1,AB2,AB3 Availability likely —
Levothyroxine Sodium 25 ug 72603-0660-01 NorthStar 90 tablets $0.036 AB1,AB2,AB3,AB4 Availability likely —
Levo-T 25 ug 55466-0104-11 Neolpharma, 90 tablets $0.036 AB1,AB2,AB3 Discontinued —
Euthyrox 25 ug 72305-0025-30 Provell 30 tablets $0.270 — Discontinued —
Levoxyl 25 ug 60793-0850-01 Pfizer 100 tablets $0.753 AB1,AB3 Availability likely —
Unithroid 25 ug 60846-0801-01 Amneal 100 tablets $4.179 AB1,AB2,AB3 Availability likely —
Synthroid 25 ugthis 00074-4341-72 AbbVie 14 tablets — AB1,AB2 FDA listed —
Levothyroxine sodium 25 ug 00480-8682-01 Teva 100 tablets — AB1,AB2,AB3,AB4 Discontinued —
Levothyroxine Sodium .025 mg 00615-8573-05 NCS 15 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine Sodium .025 mg 31722-0284-01 Camber 100 tablets — AB4 FDA listed —
Levothyroxine Sodium .025 mg 50090-4947-00 A-S 30 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine sodium 25 ug 50090-6116-00 A-S 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium .025 mg 50090-7071-00 A-S 90 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine sodium 25 ug 50090-7860-00 A-S 90 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium 25 ug 50090-7909-00 A-S 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium 25 ug 50090-7910-00 A-S 90 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium 25 ug 51655-0846-52 Northwind 30 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine Sodium .025 mg 51655-0985-52 Northwind 30 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine Sodium .025 mg 55154-3558-00 Cardinal 10 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine Sodium 25 ug 55154-5362-00 Cardinal 10 tablets — AB1,AB2,AB3,AB4 FDA listed —
levothyroxine sodium 25 ug 63629-8711-01 Bryant 1000 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium .025 mg 67046-0828-03 Coupler 30 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine Sodium .025 mg 68071-3956-09 NuCare 90 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine sodium 25 ug 68788-7969-03 Preferred 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
levothyroxine sodium 25 ug 68788-8648-03 Preferred 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine sodium 25 ug 70518-4400-00 REMEDYREPACK 90 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium .025 mg 71205-0221-30 Proficient 30 tablets — AB1,AB2,AB3 FDA listed —
Levothyroxine Sodium 25 ug 71205-0512-30 Proficient 30 tablets — AB1,AB2,AB3 FDA listed —
levothyroxine sodium 25 ug 71335-1447-01 Bryant 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine sodium 25 ug 71335-1881-01 Bryant 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
levothyroxine sodium 25 ug 71335-2287-01 Bryant 1000 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium .025 mg 71335-2549-01 Bryant 30 tablets — AB1,AB2,AB3 FDA listed —
levothyroxine sodium 25 ug 72162-1458-00 Bryant 1000 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium 25 ug 72189-0174-30 DIRECT 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine Sodium .025 mg 72865-0236-10 XLCare 1000 tablets — AB4 FDA listed —
Levothyroxine sodium 25 ug 82804-0168-30 Proficient 30 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine sodium 25 ug 87063-0083-00 ASCLEMED 1000 tablets — AB1,AB2,AB3,AB4 FDA listed —
Levothyroxine .025 mg 87448-1502-03 Northwestern 1 tablet — AB1,AB2,AB3 Discontinued —
About this product: this is the brand-name version. FDA-approved generic versions are listed, and recent pricing/market data suggests they may be available.
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

🏛️
2002
On the market since
Jul 2002
📍
2026
Currently FDA-listed
24 years listed
🔓
·
Generic versions listed
see equivalents
✅Generic appears available

FDA-approved generic versions are listed, and recent pricing/market data suggests they may be available — see Therapeutic equivalents.

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.
90 tablets00074-4341-90 70,472 Rx · $4,801,368
1000 tablets00074-4341-19 31,639 Rx · $2,193,009
7 tablets this page00074-4341-72 No Medicaid data
Drug total (last 4 qtrs): 102,111 Rx · 3,348,919 units · $6,994,377 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 Synthroid — 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 Synthroid. 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
$91.31M
Claims incl. refills
1.2M
Beneficiaries
933.5K
Spend / beneficiary
$97.81
Spend / claim
$73.69
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.

🔬 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 Synthroid (this brand).

Top reported reactions

Fatigue23,783
Nausea20,370
Headache17,383
Diarrhoea17,069
Dyspnoea15,213
Pain15,112
Dizziness14,017

Age at onset

Neonate217
Infant61
Child110
Adolescent136
Adult17,135
Elderly19,643

Reporter sex

280,388 reports
Male · 19%
Female · 80%
Unknown · 0%

Serious outcomes

Hospitalization81,408
Death18,498
Life-threatening9,575
Disabling8,343
Reports over time (by year) — tap or hover for the count & year
2023 2024 2025 2026 14,931 7,530
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 NDCDescription Per unit Per pack Marketing startStatus
00074-4341-19 1000 TABLET in 1 BOTTLE (0074-4341-19) $1.66 / ea $1,659.30 2002-07-24 Active
00074-4341-72 You're viewing this 2 BLISTER PACK in 1 CARTON (0074-4341-72) / 7 TABLET in 1 BLISTER PACK — — 2016-06-03 Active
00074-4341-90 90 TABLET in 1 BOTTLE (0074-4341-90) $1.66 / ea $149.34 2002-07-24 Active

This pack shows little to no recent Medicaid volume — the 90 tablets pack carries most fills. See all packs ↓

Pack size FAQ

What quantity is in NDC 00074-4341-72?
NDC 00074-4341-72 is a 14-count package — 2 blister pack in 1 carton / 7 tablet in 1 blister pack.
What is the difference between NDC 00074-4341-72 and NDC 00074-4341-90?
Both are Synthroid Levothyroxine Sodium 25 ug Tablet — the drug itself is identical. NDC 00074-4341-72 is the 14-count package, while NDC 00074-4341-90 is the 90 tablets package.
What NDC number is used to bill for this package of Synthroid Levothyroxine Sodium 25 ug Tablet?
Bill NDC 00074-4341-72 — the 11-digit billing format is 00074434172. 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 0074-4341-72, 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: 00074-4341-72, written without dashes as 00074434172. 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 00074-4341-72, the first segment (00074) is the labeler code FDA assigned to AbbVie Inc.; the middle segment (4341) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (72) 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 AbbVie 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 2 other package presentations of this same product, including 90 tablets (00074-4341-90), 1000 tablets (00074-4341-19). 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?
AbbVie 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 🔄 Drug / Laboratory Test 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
🚨 Boxed Warning 157 words ▾

WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS Thyroid hormones, including SYNTHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life - threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects [see Adverse Reactions ( 6 ), Drug Interactions ( 7.7 ), and Overdosage ( 10 )] .

WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS See full prescribing information for complete boxed warning . Thyroid hormones, including SYNTHROID , should not be used for the treatment of obesity or for weight loss. Doses beyond the range of daily hormonal requirements may produce serious or even life - threatening manifestations of toxicity ( 6 , 10 ).

🎯 Indications and Usage 208 words ▾

1 INDICATIONS AND USAGE Hypothyroidism SYNTHROID is indicated in adult and pediatric patients, including neonates, as a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism. Pituitary Thyrotropin (Thyroid -Stimulating Hormone, TSH) Suppression SYNTHROID is indicated in adult and pediatric patients, including neonates, as an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer.

Limitations of Use SYNTHROID is not indicated for suppression of benign thyroid nodules and nontoxic diffuse goiter in iodine-sufficient patients as there are no clinical benefits and overtreatment with SYNTHROID may induce hyperthyroidism [see Warnings and Precautions ( 5.1 )]. SYNTHROID is not indicated for treatment of hypothyroidism during the recovery phase of subacute thyroiditis. SYNTHROID is a L-thyroxine (T4) indicated in adult and pediatric patients, including neonates, for: Hypothyroidism: As replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism.

( 1 ) Pituitary Thyrotropin (Thyroid-Stimulating Hormone, TSH) Suppression: As an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer. ( 1 ) Limitations of Use: Not indicated for suppression of benign thyroid nodules and nontoxic diffuse goiter in iodine-sufficient patients Not indicated for treatment of hypothyroidism during the recovery phase of subacute thyroiditis

⏱️ Dosage and Administration ~3 min read ▾

2 DOSAGE AND ADMINISTRATION Administer once daily, preferably on an empty stomach, one-half to one hour before breakfast. ( 2.1 ) Administer at least 4 hours before or after drugs that are known to interfere with absorption. ( 2.1 ) Evaluate the need for dose adjustments when regularly administering within one hour of certain foods that may affect absorption.

( 2.1 ) Advise patients to stop biotin and biotin-containing supplements at least 2 days before assessing TSH and/or T4 levels. ( 2.2 ) Starting dose depends on a variety of factors, including age, body weight, cardiovascular status, and concomitant medications. Peak therapeutic effect may not be attained for 4-6 weeks.

( 2.2 ) See full prescribing information for dosing in specific patient populations. ( 2.3 ) Adequacy of therapy determined with periodic monitoring of TSH and/or T4 as well as clinical status. ( 2.4 )

2.1Important Administration Instructions Administer SYNTHROID as a single daily dose, on an empty stomach, one-half to one hour before breakfast. Administer SYNTHROID at least 4 hours before or after drugs known to interfere with SYNTHROID absorption [see Drug Interactions ( 7.1 ) ] . Evaluate the need for dosage adjustments when regularly administering within one hour of certain foods that may affect SYNTHROID absorption [see Dosage and Administration ( 2.2 and 2.3 ), Drug Interactions ( 7.9 ) , and Clinical Pharmacology ( 12.3 ) ] .

Administer SYNTHROID to pediatric patients who cannot swallow intact tablets by crushing the tablet, suspending the freshly crushed tablet in a small amount (5 to 10 mL) of water and immediately administering the suspension by spoon or dropper. Ensure the patient ingests the full amount of the suspension. Do not store the suspension.

Do not administer in foods that decrease absorption of SYNTHROID, such as soybean-based infant formula [see Drug Interactions ( 7.9 ) ] .

2.2Important Considerations for Dosing The dosage of SYNTHROID for hypothyroidism or pituitary TSH suppression depends on a variety of factors including: the patient's age, body weight, cardiovascular status, concomitant medical conditions (including pregnancy), concomitant medications, co-administered food and the specific nature of the condition being treated [see Dosage and Administration ( 2.3 ), Warnings and Precautions ( 5 ), and Drug Interactions ( 7 )] . Dosing must be individualized to account for these factors and dosage adjustments made based on periodic assessment of the patient's clinical response and laboratory parameters [see Dosage and Administration ( 2.4 )] .

For adult patients with primary hypothyroidism, titrate until the patient is clinically euthyroid and the serum TSH returns to normal [see Dosage and Administration ( 2.3 )] . For secondary or tertiary hypothyroidism, serum TSH is not a reliable measure of SYNTHROID dosage adequacy and should not be used to monitor therapy. Use the serum free-T4 level to titrate SYNTHROID dosing until the patient is clinically euthyroid and the serum free-T4 level is restored to the upper half of the normal range [see Dosage and Administration ( 2.3 )] .

Inquire whether patients are taking biotin or biotin-containing supplements. If so, advise them to stop biotin supplementation at least 2 days before assessing TSH and/or T4 levels [see Dosage and Administration ( 2.4 ) and Drug Interactions ( 7.10 )]. The peak therapeutic effect of a given dose of SYNTHROID may not be attained for 4 to 6 weeks.

2.3Recommended Dosage and Titration Primary, Secondary, and Tertiary Hypothyroidism in Adults The recommended starting daily dosage of SYNTHROID in adults with primary, secondary, or tertiary hypothyroidism is based on age and comorbid cardiac conditions, as described in Table 1. For patients at risk of atrial fibrillation or patients with underlying cardiac disease, start with a lower dosage and titrate the dosage more slowly to avoid exacerbation of cardiac symptoms. Dosage titration is based on serum TSH or fr…

💊 Dosage Forms and Strengths 119 words ▾

3 DOSAGE FORMS AND STRENGTHS SYNTHROID tablets are available as follows ( Table 4 ): Table 4: SYNTHROID Tablet Strengths and Identifying Features Tablet Strength Tablet Color/Shape Tablet Markings 25 mcg Orange/Round “SYNTHROID” and “25” 50 mcg White/Round “SYNTHROID” and “50” 75 mcg Violet/Round “SYNTHROID” and “75” 88 mcg Olive/Round “SYNTHROID” and “88” 100 mcg Yellow/Round “SYNTHROID” and “100” 112 mcg Rose/Round “SYNTHROID” and “112” 125 mcg Brown/Round “SYNTHROID” and “125” 137 mcg Turquoise/Round “SYNTHROID” and “137” 150 mcg Blue/Round “SYNTHROID” and “150” 175 mcg Lilac/Round “SYNTHROID” and “175” 200 mcg Pink/Round “SYNTHROID” and “200” 300 mcg Green/Round “SYNTHROID” and “300” Tablets: 25, 50, 75, 88, 100, 112, 125, 137, 150, 175, 200, and 300 mcg ( 3 )

⛔ Contraindications 26 words ▾

4 CONTRAINDICATIONS SYNTHROID is contraindicated in patients with uncorrected adrenal insufficiency [see Warnings and Precautions ( 5.4 ) ] . Uncorrected adrenal insufficiency. ( 4 )

⚠️ Warnings and Cautions ~3 min read ▾

5 WARNINGS AND PRECAUTIONS Serious risks related to overtreatment or undertreatment with SYNTHROID: Titrate the dose of SYNTHROID carefully and monitor response to titration. ( 5.1 ) Cardiac adverse reactions in the elderly and in patients with underlying cardiovascular disease: Initiate SYNTHROID at less than the full replacement dose because of the increased risk of cardiac adverse reactions, including atrial fibrillation. ( 2.3 , 5.2 , 8.5 ) Myxedema coma: Do not use oral thyroid hormone drug products to treat myxedema coma.

( 5.3 ) Acute adrenal crisis in patients with concomitant adrenal insufficiency: Treat with replacement glucocorticoids prior to initiation of SYNTHROID treatment. ( 5.4 ) Worsening of diabetic control: Therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control after starting, changing, or discontinuing thyroid hormone therapy.

( 5.5 ) Decreased bone mineral density associated with thyroid hormone over-replacement: Over-replacement can increase bone resorption and decrease bone mineral density. Give the lowest effective dose. ( 5.6 )

5.1Serious Risks Related to Overtreatment or Undertreatment with SYNTHROID SYNTHROID has a narrow therapeutic index. Overtreatment or undertreatment with SYNTHROID may have negative effects on growth and development, cardiovascular function, bone metabolism, reproductive function, cognitive function, gastrointestinal function, and glucose and lipid metabolism in adult or pediatric patients. In pediatric patients with congenital and acquired hypothyroidism, undertreatment may adversely affect cognitive development and linear growth, and overtreatment is associated with craniosynostosis and acceleration of bone age [see Use in Specific Populations ( 8.4 )] .

Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects [see Dosage and Administration (2.4) ] . Consider the potential for food or drug interactions and adjust the administration or dosage of SYNTHROID as needed [see Dosage and Administration ( 2.1 ), Drug Interactions (7.1) , and Clinical Pharmacology (12.3) ] . 5.

2 Cardiac Adverse Reactions in the Elderly and in Patients with Underlying Cardiovascular Disease Over-treatment with levothyroxine may cause an increase in heart rate, cardiac wall thickness, and cardiac contractility and may precipitate angina or arrhythmias, particularly in patients with cardiovascular disease and in elderly patients. Initiate SYNTHROID therapy in this population at lower doses than those recommended in younger individuals or in patients without cardiac disease [see Dosage and Administration ( 2.3 ) and Use in Specific Populations ( 8.5 ) ] .

Monitor for cardiac arrhythmias during surgical procedures in patients with coronary artery disease receiving suppressive SYNTHROID therapy. Monitor patients receiving concomitant SYNTHROID and sympathomimetic agents for signs and symptoms of coronary insufficiency. If cardiac symptoms develop or worsen, reduce the SYNTHROID dose or withhold for one week and restart at a lower dose.

5. 3 Myxedema Coma Myxedema coma is a life-threatening emergency characterized by poor circulation and hypometabolism and may result in unpredictable absorption of levothyroxine sodium from the gastrointestinal tract. Use of oral thyroid hormone drug products is not recommended to treat myxedema coma.

Administer thyroid hormone products formulated for intravenous administration to treat myxedema coma. 5. 4 Acute Adrenal Crisis in Patients with Concomitant Adrenal Insufficiency Thyroid hormone increases metabolic clearance of glucocorticoids.

Initiation of thyroid hormone therapy prior to initiating glucocorticoid therapy may precipitate an acute adrenal crisis in patients with adrenal insufficiency. Treat patients with adrenal insufficiency with replacement glucocorticoids prior to initiating treatment with SYNTHROID […

🤒 Adverse Reactions ~1 min read ▾

6 ADVERSE REACTIONS Adverse reactions associated with SYNTHROID therapy are primarily those of hyperthyroidism due to therapeutic overdosage [see Warnings and Precautions ( 5 ) and Overdosage ( 10 ) ] . They include the following: General: fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating Central nervous system: headache, hyperactivity, nervousness, anxiety, irritability, emotional lability, insomnia Musculoskeletal: tremors, muscle weakness, muscle spasm Cardiovascular: palpitations, tachycardia, arrhythmias, increased pulse and blood pressure, heart failure, angina, myocardial infarction, cardiac arrest Respiratory: dyspnea Gastrointestinal: diarrhea, vomiting, abdominal cramps, elevations in liver function tests Dermatologic: hair loss, flushing, rash Endocrine: decreased bone mineral density Reproductive: menstrual irregularities, impaired fertility Seizures have been reported rarely with the institution of levothyroxine therapy.

Adverse Reactions in Pediatric Patients Pseudotumor cerebri and slipped capital femoral epiphysis have been reported in pediatric patients receiving levothyroxine therapy. Overtreatment may result in craniosynostosis in infants who have not undergone complete closure of the fontanelles, and in premature closure of the epiphyses in pediatric patients still experiencing growth with resultant compromised adult height. Hypersensitivity Reactions Hypersensitivity reactions to inactive ingredients have occurred in patients treated with thyroid hormone products.

These include urticaria, pruritus, skin rash, flushing, angioedema, various gastrointestinal symptoms (abdominal pain, nausea, vomiting and diarrhea), fever, arthralgia, serum sickness, and wheezing. Hypersensitivity to levothyroxine itself is not known to occur. Adverse reactions associated with SYNTHROID therapy are primarily those of hyperthyroidism due to therapeutic overdosage: arrhythmias, myocardial infarction, dyspnea, muscle spasm, headache, nervousness, irritability, insomnia, tremors, muscle weakness, increased appetite, weight loss, diarrhea, heat intolerance, menstrual irregularities, and skin rash.

( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact AbbVie Inc. at 1-800-633-9110 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

🔄 Drug Interactions ~2 min read ▾

7 DRUG INTERACTIONS See full prescribing information for drugs that affect thyroid hormone pharmacokinetics and metabolism (e.g., absorption, synthesis, secretion, catabolism, protein binding, and target tissue response) and may alter the therapeutic response to SYNTHROID. ( 7 )

7.1Drugs Known to Affect Thyroid Hormone Pharmacokinetics Many drugs can exert effects on thyroid hormone pharmacokinetics and metabolism (e.g., absorption, synthesis, secretion, catabolism, protein binding, and target tissue response) and may alter the therapeutic response to SYNTHROID ( Tables 5 to 8 ). Table 5. Drugs That May Decrease T4 Absorption (Hypothyroidism) Potential impact: Concurrent use may reduce the efficacy of SYNTHROID by binding and delaying or preventing absorption, potentially resulting in hypothyroidism.

Drug or Drug Class Effect Phosphate Binders (e.g., calcium carbonate, ferrous sulfate, sevelamer, lanthanum) Phosphate binders may bind to levothyroxine. Administer SYNTHROID at least 4 hours apart from these agents. Orlistat Monitor patients treated concomitantly with orlistat and SYNTHROID for changes in thyroid function.

Bile Acid Sequestrants (e.g., colesevelam, cholestyramine, colestipol) Ion Exchange Resins (e.g., Kayexalate) Bile acid sequestrants and ion exchange resins are known to decrease levothyroxine absorption. Administer SYNTHROID at least 4 hours prior to these drugs or monitor TSH levels. Proton Pump Inhibitors Sucralfate Antacids (e.g., aluminum & magnesium hydroxides, simethicone) Gastric acidity is an essential requirement for adequate absorption of levothyroxine.

Sucralfate, antacids and proton pump inhibitors may cause hypochlorhydria, affect intragastric pH, and reduce levothyroxine absorption. Monitor patients appropriately. Table 6.

Drugs That May Alter T4 and Triiodothyronine (T3) Serum Transport Without Affecting Free Thyroxine (FT4) Concentration (Euthyroidism) Drug or Drug Class Effect Clofibrate Estrogen-containing oral contraceptives Estrogens (oral) Heroin / Methadone 5-Fluorouracil Mitotane Tamoxifen These drugs may increase serum thyroxine-binding globulin (TBG) concentration. Androgens / Anabolic Steroids Asparaginase Glucocorticoids Slow-Release Nicotinic Acid These drugs may decrease serum TBG concentration. Potential impact (below): Administration of these agents with SYNTHROID results in an initial transient increase in FT4.

Continued administration results in a decrease in serum T4 and normal FT4 and TSH concentrations. Salicylates (> 2 g/day) Salicylates inhibit binding of T4 and T3 to TBG and transthyretin. An initial increase in serum FT4 is followed by return of FT4 to normal levels with sustained therapeutic serum salicylate concentrations, although total T4 levels may decrease by as much as 30%.

Other drugs: Carbamazepine Furosemide (> 80 mg IV) Heparin Hydantoins Non-Steroidal Anti-inflammatory Drugs - Fenamates These drugs may cause protein-binding site displacement. Furosemide has been shown to inhibit the protein binding of T4 to TBG and albumin, causing an increase free T4 fraction in serum. Furosemide competes for T4-binding sites on TBG, prealbumin, and albumin, so that a single high dose can acutely lower the total T4 level.

Phenytoin and carbamazepine reduce serum protein binding of levothyroxine, and total and free T4 may be reduced by 20% to 40%, but most patients have normal serum TSH levels and are clinically euthyroid. Closely monitor thyroid hormone parameters. Table 7.

Drugs That May Alter Hepatic Metabolism of T4 (Hypothyroidism) Potential impact: Stimulation of hepatic microsomal drug-metabolizing enzyme activity may cause increased hepatic degradation of levothyroxine, resulting in increased SYNTHROID requirements. Drug or Drug Class Effect Phenobarbital Rifampin Phenobarbital has been shown to reduce the response to thyroxine. Phenobarbital increases L-thyroxine metabolism by inducing uridine 5’-diphospho-glucuronosyltransferase (UGT) and leads to lower T4 serum le…

🔄 Drug / Laboratory Test Interactions 122 words ▾

7.10Drug-Laboratory Test Interactions Thyroxine-binding Globulin (TBG) Consider changes in TBG concentration when interpreting T4 and T3 values. Measure and evaluate unbound (free) hormone and/or determine the free-T4 index (FT4I) in this circumstance. Pregnancy, infectious hepatitis, estrogens, estrogen-containing oral contraceptives, and acute intermittent porphyria increase TBG concentration.

Nephrosis, severe hypoproteinemia, severe liver disease, acromegaly, androgens, and corticosteroids decrease TBG concentration. Familial hyper- or hypo-thyroxine binding globulinemias have been described, with the incidence of TBG deficiency approximating 1 in 9000. Biotin Biotin supplementation is known to interfere with thyroid hormone immunoassays that are based on a biotin and streptavidin interaction, which may result in erroneous thyroid hormone test results.

Stop biotin and biotin-containing supplements for at least 2 days prior to thyroid testing.

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS Pregnancy may require the use of higher doses of SYNTHROID. ( 2.3 , 8.1 )

8.1Pregnancy Risk Summary The clinical experience, including data from postmarketing studies, in pregnant women treated with oral levothyroxine to maintain euthyroid state have not reported increased rates of major birth defects, miscarriages, or other adverse maternal or fetal outcomes . There are risks to the mother and fetus associated with untreated hypothyroidism in pregnancy. Since TSH levels may increase during pregnancy, TSH should be monitored and SYNTHROID dosage adjusted during pregnancy (see Clinical Considerations) .

Animal reproductive studies have not been conducted with levothyroxine sodium. SYNTHROID should not be discontinued during pregnancy and hypothyroidism diagnosed during pregnancy should be promptly treated. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown.

All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. 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. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Maternal hypothyroidism during pregnancy is associated with a higher rate of complications, including spontaneous abortion, gestational hypertension, pre-eclampsia, stillbirth, and premature delivery.

Untreated maternal hypothyroidism may have an adverse effect on fetal neurocognitive development. Dose Adjustments During Pregnancy and the Postpartum Period Pregnancy may increase SYNTHROID requirements. Serum TSH levels should be monitored and the SYNTHROID dosage adjusted during pregnancy.

Since postpartum TSH levels are similar to preconception values, the SYNTHROID dosage should return to the pre-pregnancy dose immediately after delivery [see Dosage and Administration ( 2.3 ) ].

8.2Lactation Risk Summary Published studies report that levothyroxine is present in human milk following the administration of oral levothyroxine. No adverse effects on the breastfed infant have been reported and there is no information on the effects of levothyroxine on milk production. Adequate levothyroxine treatment during lactation may normalize milk production in hypothyroid lactating mothers with low milk supply.

The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for SYNTHROID and any potential adverse effects on the breastfed infant from SYNTHROID or from the underlying maternal condition.

8.4Pediatric Use SYNTHROID is indicated in patients from birth to less than 17 years of age: As a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism. As an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer. Rapid restoration of normal serum T4 concentrations is essential for preventing the adverse effects of congenital hypothyroidism on cognitive development as well as on overall physical growth and maturation.

Therefore, initiate SYNTHROID therapy immediately upon diagnosis. Levothyroxine is generally continued for life in these patients [ see Warnings and Precautions ( 5.1 ) ] . Closely monitor infants during the first 2 weeks of SYNTHROID therapy for cardiac overload and arrhythmias.

8.5Geriatric Use Because of the increased prevalence of cardiovascular disease among the elderly, initiate SYNTHROID at less than the full replacement dose [see Dosage and Administration ( 2.3 ) and Warnings and Precautions ( 5.2 ) ] . Atrial arrhythmias can occur in elderly patients. Atrial fibrillation is the most common of the arrhythmias observed with levothyroxine overtreatment in the elderly.

🤰 Pregnancy ~1 min read ▾

8.1Pregnancy Risk Summary The clinical experience, including data from postmarketing studies, in pregnant women treated with oral levothyroxine to maintain euthyroid state have not reported increased rates of major birth defects, miscarriages, or other adverse maternal or fetal outcomes . There are risks to the mother and fetus associated with untreated hypothyroidism in pregnancy. Since TSH levels may increase during pregnancy, TSH should be monitored and SYNTHROID dosage adjusted during pregnancy (see Clinical Considerations) .

Animal reproductive studies have not been conducted with levothyroxine sodium. SYNTHROID should not be discontinued during pregnancy and hypothyroidism diagnosed during pregnancy should be promptly treated. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown.

All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. 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. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Maternal hypothyroidism during pregnancy is associated with a higher rate of complications, including spontaneous abortion, gestational hypertension, pre-eclampsia, stillbirth, and premature delivery.

Untreated maternal hypothyroidism may have an adverse effect on fetal neurocognitive development. Dose Adjustments During Pregnancy and the Postpartum Period Pregnancy may increase SYNTHROID requirements. Serum TSH levels should be monitored and the SYNTHROID dosage adjusted during pregnancy.

Since postpartum TSH levels are similar to preconception values, the SYNTHROID dosage should return to the pre-pregnancy dose immediately after delivery [see Dosage and Administration ( 2.3 ) ].

🧒 Pediatric Use 120 words ▾

8.4Pediatric Use SYNTHROID is indicated in patients from birth to less than 17 years of age: As a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism. As an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer. Rapid restoration of normal serum T4 concentrations is essential for preventing the adverse effects of congenital hypothyroidism on cognitive development as well as on overall physical growth and maturation.

Therefore, initiate SYNTHROID therapy immediately upon diagnosis. Levothyroxine is generally continued for life in these patients [ see Warnings and Precautions ( 5.1 ) ] . Closely monitor infants during the first 2 weeks of SYNTHROID therapy for cardiac overload and arrhythmias.

🧓 Geriatric Use 62 words ▾

8.5Geriatric Use Because of the increased prevalence of cardiovascular disease among the elderly, initiate SYNTHROID at less than the full replacement dose [see Dosage and Administration ( 2.3 ) and Warnings and Precautions ( 5.2 ) ] . Atrial arrhythmias can occur in elderly patients. Atrial fibrillation is the most common of the arrhythmias observed with levothyroxine overtreatment in the elderly.

🆘 Overdosage 117 words ▾

10 OVERDOSAGE The signs and symptoms of overdosage are those of hyperthyroidism [see Warnings and Precautions ( 5 ) and Adverse Reactions ( 6 ) ] . In addition, confusion and disorientation may occur. Cerebral embolism, shock, coma, and death have been reported.

Seizures occurred in a 3-year-old child ingesting 3.6 mg of levothyroxine. Symptoms may not necessarily be evident or may not appear until several days after ingestion of levothyroxine sodium. Reduce the SYNTHROID dosage or discontinue temporarily if signs or symptoms of overdosage occur.

Initiate appropriate supportive treatment as dictated by the patient’s medical status. For current information on the management of poisoning or overdosage, contact the National Poison Control Center at 1-800-222-1222 or www.poison.org.

🧬 Clinical Pharmacology ~2 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Thyroid hormones exert their physiologic actions through control of DNA transcription and protein synthesis. Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell nucleus and bind to thyroid receptor proteins attached to DNA. This hormone nuclear receptor complex activates gene transcription and synthesis of messenger RNA and cytoplasmic proteins.

The physiological actions of thyroid hormones are produced predominantly by T3, the majority of which (approximately 80%) is derived from T4 by deiodination in peripheral tissues.

12.2Pharmacodynamics Oral levothyroxine sodium is a synthetic T4 hormone that exerts the same physiologic effect as endogenous T4, thereby maintaining normal T4 levels when a deficiency is present.

12.3Pharmacokinetics Absorption Absorption of orally administered T4 from the gastrointestinal tract ranges from 40% to 80%. The majority of the SYNTHROID dose is absorbed from the jejunum and upper ileum. The relative bioavailability of SYNTHROID tablets, compared to an equal nominal dose of oral levothyroxine sodium solution, is approximately 93%.

T4 absorption is increased by fasting, and decreased in malabsorption syndromes and by certain foods such as soybeans. Dietary fiber decreases bioavailability of T4. Absorption may also decrease with age.

In addition, many drugs and foods affect T4 absorption [see Drug Interactions ( 7 ) ] . Distribution Circulating thyroid hormones are greater than 99% bound to plasma proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA), and albumin (TBA), whose capacities and affinities vary for each hormone. The higher affinity of both TBG and TBPA for T4 partially explains the higher serum levels, slower metabolic clearance, and longer half-life of T4 compared to T3.

Protein-bound thyroid hormones exist in reverse equilibrium with small amounts of free hormone. Only unbound hormone is metabolically active. Many drugs and physiologic conditions affect the binding of thyroid hormones to serum proteins [see Drug Interactions ( 7 ) ] .

Thyroid hormones do not readily cross the placental barrier [see Use in Specific Populations ( 8.1 ) ] . Elimination Metabolism T4 is slowly eliminated (see Table 10 ). The major pathway of thyroid hormone metabolism is through sequential deiodination.

Approximately 80% of circulating T3 is derived from peripheral T4 by monodeiodination. The liver is the major site of degradation for both T4 and T3, with T4 deiodination also occurring at a number of additional sites, including the kidney and other tissues. Approximately 80% of the daily dose of T4 is deiodinated to yield equal amounts of T3 and reverse T3 (rT3).

T3 and rT3 are further deiodinated to diiodothyronine. Thyroid hormones are also metabolized via conjugation with glucuronides and sulfates and excreted directly into the bile and gut where they undergo enterohepatic recirculation. Excretion Thyroid hormones are primarily eliminated by the kidneys.

A portion of the conjugated hormone reaches the colon unchanged and is eliminated in the feces. Approximately 20% of T4 is eliminated in the stool. Urinary excretion of T4 decreases with age.

Table 10. Pharmacokinetic Parameters of Thyroid Hormones in Euthyroid Patients Hormone Ratio in Thyroglobulin Biologic Potency t 1/2 (days) Protein Binding (%)* Levothyroxine (T4) 10 - 20 1 6-7**

99.96Liothyronine (T3) 1 4 ≤ 2 99.5 * Includes TBG, TBPA, and TBA ** 3 to 4 days in hyperthyroidism, 9 to 10 days in hypothyroidism

🧬 Mechanism of Action 79 words ▾

12.1Mechanism of Action Thyroid hormones exert their physiologic actions through control of DNA transcription and protein synthesis. Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell nucleus and bind to thyroid receptor proteins attached to DNA. This hormone nuclear receptor complex activates gene transcription and synthesis of messenger RNA and cytoplasmic proteins.

The physiological actions of thyroid hormones are produced predominantly by T3, the majority of which (approximately 80%) is derived from T4 by deiodination in peripheral tissues.

📦 How Supplied / Storage and Handling 180 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING How Supplied SYNTHROID (levothyroxine sodium, USP) tablets are supplied as follows ( Table 11 ): Table 11: SYNTHROID Tablet Presentations Strength (mcg) Color/Shape Tablet Markings NDC# for bottles of 90 NDC # for bottles of 1000 NDC # for unit dose cartons of 100 25 Orange/Round “SYNTHROID” and “25” 0074-4341-90 0074-4341-19 -- 50 White/Round “SYNTHROID” and “50” 0074-4552-90 0074-4552-19 0074-4552-11 75 Violet/Round “SYNTHROID” and “75” 0074-5182-90 0074-5182-19 0074-5182-11 88 Olive/Round “SYNTHROID” and “88” 0074-6594-90 0074-6594-19 -- 100 Yellow/Round “SYNTHROID” and “100” 0074-6624-90 0074-6624-19 0074-6624-11 112 Rose/Round “SYNTHROID” and “112” 0074-9296-90 0074-9296-19 -- 125 Brown/Round “SYNTHROID” and “125” 0074-7068-90 0074-7068-19 0074-7068-11 137 Turquoise/Round “SYNTHROID” and “137” 0074-3727-90 0074-3727-19 -- 150 Blue/Round “SYNTHROID” and “150” 0074-7069-90 0074-7069-19 0074-7069-11 175 Lilac/Round “SYNTHROID” and “175” 0074-7070-90 0074-7070-19 -- 200 Pink/Round “SYNTHROID” and “200” 0074-7148-90 0074-7148-19 0074-7148-11 300 Green/Round “SYNTHROID” and “300” 0074-7149-90 0074-7149-19 -- Storage and Handling Store SYNTHROID at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) (see USP Controlled Room Temperature).

SYNTHROID tablets should be protected from light and moisture.

📋 Description ~2 min read ▾

11 DESCRIPTION SYNTHROID (levothyroxine sodium tablets, USP) is L-thyroxine (T4) and contains synthetic crystalline L-3,3',5,5'-tetraiodothyronine sodium salt. Synthetic T4 is chemically identical to that produced in the human thyroid gland. Levothyroxine (T4) sodium has an empirical formula of C 15 H 10 I 4 N NaO 4 • H 2 O, molecular weight of 798.86 (anhydrous), and structural formula as shown: SYNTHROID tablets for oral administration are supplied in the following strengths: 25 mcg, 50 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, 200 mcg, and 300 mcg.

Each SYNTHROID tablet contains the inactive ingredients acacia, confectioner's sugar (contains corn starch), lactose monohydrate, magnesium stearate, povidone, and talc. SYNTHROID tablets contain no ingredients made from a gluten-containing grain (wheat, barley, or rye). Each tablet strength meets USP Dissolution Test 3.

Table 9 provides a listing of the color additives by tablet strength: Table 9: SYNTHROID Tablet Color Additives Strength (mcg) Color additive(s) 25 FD&C Yellow No. 6 Aluminum Lake* 50 None 75 FD&C Red No. 40 Aluminum Lake, FD&C Blue No.

2 Aluminum Lake 88 FD&C Blue No. 1 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake*, D&C Yellow No.

10 Aluminum Lake 100 D&C Yellow No. 10 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake* 112 D&C Red No.

27 & 30 Aluminum Lake 125 FD&C Yellow No. 6 Aluminum Lake*, FD&C Red No. 40 Aluminum Lake, FD&C Blue No.

1 Aluminum Lake 137 FD&C Blue No. 1 Aluminum Lake 150 FD&C Blue No. 2 Aluminum Lake 175 FD&C Blue No.

1 Aluminum Lake, D&C Red No. 27 & 30 Aluminum Lake 200 FD&C Red No. 40 Aluminum Lake 300 D&C Yellow No.

10 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake*, FD&C Blue No. 1 Aluminum Lake * Note – FD&C Yellow No.

6 is orange in color. SYNTHROID (levothyroxine sodium tablets, USP) contain synthetic crystalline L-3,3',5,5'-tetraiodothyronine sodium salt [levothyroxine (T4) sodium]. Synthetic T4 is chemically identical to that produced in the human thyroid gland.

Levothyroxine (T4) sodium has an empirical formula of C15H10I4N NaO4• H2O, molecular weight of 798.86 (anhydrous), and structural formula as shown:

💬 Information for Patients ~2 min read ▾

17 PATIENT COUNSELING INFORMATION Inform the patient of the following information to aid in the safe and effective use of SYNTHROID: Dosing and Administration Instruct patients to take SYNTHROID only as directed by their healthcare provider. Instruct patients to take SYNTHROID as a single dose, preferably on an empty stomach, one-half to one hour before breakfast. Inform patients that agents such as iron and calcium supplements and antacids can decrease the absorption of levothyroxine.

Instruct patients not to take SYNTHROID tablets within 4 hours of these agents. Instruct patients to notify their healthcare provider if they are pregnant or breastfeeding or are thinking of becoming pregnant while taking SYNTHROID. Important Information Inform patients that it may take several weeks before they notice an improvement in symptoms.

Inform patients that the levothyroxine in SYNTHROID is intended to replace a hormone that is normally produced by the thyroid gland. Generally, replacement therapy is to be taken for life. Inform patients that SYNTHROID should not be used as a primary or adjunctive therapy in a weight control program.

Instruct patients to notify their healthcare provider if they are taking any other medications, including prescription and over-the-counter preparations. Instruct patients to discontinue biotin or any biotin-containing supplements for at least 2 days before thyroid function testing is conducted. Instruct patients to notify their physician of any other medical conditions they may have, particularly heart disease, diabetes, clotting disorders, and adrenal or pituitary gland problems, as the dose of medications used to control these other conditions may need to be adjusted while they are taking SYNTHROID.

If they have diabetes, instruct patients to monitor their blood and/or urinary glucose levels as directed by their physician and immediately report any changes to their physician. If patients are taking anticoagulants, their clotting status should be checked frequently. Instruct patients to notify their physician or dentist that they are taking SYNTHROID prior to any surgery.

Adverse Reactions Instruct patients to notify their healthcare provider if they experience any of the following symptoms: rapid or irregular heartbeat, chest pain, shortness of breath, leg cramps, headache, nervousness, irritability, sleeplessness, tremors, change in appetite, weight gain or loss, vomiting, diarrhea, excessive sweating, heat intolerance, fever, changes in menstrual periods, hives or skin rash, or any other unusual medical event. Inform patients that partial hair loss may occur rarely during the first few months of SYNTHROID therapy, but this is usually temporary. © 2024 AbbVie Inc.

All rights reserved. SYNTHROID and its design are trademarks of AbbVie Inc. AbbVie Inc.

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