Levothyroxine Sodium

Manages thyrotropin-dependent well-differentiated thyroid cancer. Sold as Thyro-Tabs, Levolet, Unithroid, Euthyrox, Levoxyl and 7 more. Every FDA application for this active ingredient: 14 branded and 20 generic.

As of Nov 15, 2026, FDA lists 34 applications for Levothyroxine Sodium (sold as Thyro-Tabs, Levolet, Unithroid and others), first approved Aug 21, 2000, with 13 new uses approved and 0 published complete response letters.

First approved: Aug 21, 2000
Applications: 34
New uses approved: 13
Complete response letters: 0
Medicare spending, 2025: $839M

Medicare Spending

CMS Part D and Part B, 2025, before manufacturer rebates; matched by generic name


Levothyroxine Sodium	Part D	$449M	-3%	9,214,089
Synthroid	Part D	$358M	+3%	1,171,133
Tirosint	Part D	$19.0M	+15%	17,054
Levoxyl	Part D	$6.1M	+1%	42,754
Tirosint-Sol	Part D	$3.9M	+49%	3,679
Unithroid	Part D	$2.9M	-30%	32,999
Thyquidity	Part D	$282K	+10%	353
Euthyrox	Part D	$175K	-64%	14,361
LEVOTHYROXINE SODIUM(J0651)	Part B	$160K	New	157
Ermeza	Part D	$38K	+116%	54
Levo-T	Part D	$29K	-84%	924
LEVOTHYROXINE SODIUM(J0650)	Part B	$23K	New	0

What Pharmacies Pay

Median price per unit across package codes in CMS's weekly NADAC survey, Nov 11, 2026, before rebates; see every drug's price change

LEVOTHYROXINE 100 MCG TABLET: $0.050 per unitGeneric · -12% in a year
LEVOTHYROXINE 112 MCG TABLET: $0.058 per unitGeneric · -13% in a year
LEVOTHYROXINE 125 MCG TABLET: $0.058 per unitGeneric · -11% in a year
LEVOTHYROXINE 137 MCG TABLET: $0.063 per unitGeneric · -14% in a year
LEVOTHYROXINE 150 MCG TABLET: $0.057 per unitGeneric · -22% in a year
LEVOTHYROXINE 175 MCG TABLET: $0.075 per unitGeneric · -20% in a year
LEVOTHYROXINE 200 MCG TABLET: $0.085 per unitGeneric · -1% in a year
LEVOTHYROXINE 25 MCG TABLET: $0.035 per unitGeneric · -15% in a year
LEVOTHYROXINE 300 MCG TABLET: $0.109 per unitGeneric · -6% in a year
LEVOTHYROXINE 50 MCG TABLET: $0.040 per unitGeneric · -23% in a year
LEVOTHYROXINE 75 MCG TABLET: $0.047 per unitGeneric · -13% in a year
LEVOTHYROXINE 88 MCG TABLET: $0.048 per unitGeneric · -17% in a year

Orphan Designations (FDA)

One designation, 0 approved for the designated use; see all orphan designations

The preservation of organ function in brain-dead organ donors.Fera Pharmaceuticals, LLC · designated Apr 26, 2011

Approvals in Japan (PMDA)

PMDA's English list since 2008, matched by ingredient; see all Japanese approvals

Thyradin-S, new approvalA drug with a new route of administration indicated for the treatment of myxedema coma and hypothyroidism (for hypothyroidism, only in patients ineligible… · Aska Pharmaceutical Co., Ltd. · Jan 23, 2020

Clinical Trials

39 open or ongoing studies name this ingredient as an intervention, including as a comparator; newest first. See all


Validation of Uzbek SARC-F and IPAQ-SF Questionnaires in Adults With and Without HypothyroidismHypothyroidism, Psychometrics · Andijan State Medical Institute	—	Not yet recruiting	Nov 6, 2026
Comparison of Two Timings of Levothyroxine Intake in Hypothyroid Patients: A Cross-over Randomized Control TrialHypothyroidism Primary · Elyes Kamoun	Phase 4	Active, not recruiting	Oct 28, 2026
Discontinuation of Low-Dose Levothyroxine in Older Adults With Subclinical HypothyroidismHypothyroidism · Spyridoula Maraka	Phase 4	Not yet recruiting	Aug 26, 2026
Vitamin E Add-On Therapy, Thyroid Function & Oxidative Stress in Levothyroxine-Treated HypothyroidismHypothyroidism · Bangladesh Medical University	Not applicable	Enrolling by invitation	Aug 24, 2026
Evaluation of Levothyroxine Replacement Therapy After Total Thyroidectomy Using a Smart WristbandTotal Thyroidectomy, Hyperthyroidism · Yeditepe University Hospital	Not applicable	Recruiting	Jul 29, 2026
Effect of Medication Adherence-Based Digital Intervention on Fatigue Severity, Weight, and Thyroid Hormone RegulationHypothyroidism · University of Baghdad	Not applicable	Not yet recruiting	Jun 9, 2026
Thyroxine Supplementation in Small for Gestational Age (SGA) Infants With Birth Weight <1500g and TSH 6-20 mIU/mlThyroid Function, Preterm · Shandong Provincial Hospital	Not applicable	Not yet recruiting	Jun 4, 2026
Additive Efficacy of Physical Activity Program in Hypthyroidism Elder Females With Glaucoma and Fatty Liver IssuesSubclinical hypothyroïdism, Non-Alcoholic Fatty Liver Disease · Cairo University	Not applicable	Recruiting	May 20, 2026

Applications

NDAs, BLAs and generic ANDAs for this ingredient, oldest first; each opens its full history


Aug 21, 2000	UnithroidNDA 21210 · TYPE 7	Stevens J	7	Marketed
May 25, 2001	LevoxylNDA 21301 · New formulation or manufacturer	King Pharms	12	Marketed
Mar 1, 2002	Levo-TNDA 21342 · New formulation or manufacturer	Cediprof Inc	13	Marketed
May 31, 2002	EuthyroxNDA 21292 · New formulation or manufacturer	Emd Serono Inc	5	Discontinued
Jun 5, 2002	Levothyroxine SodiumANDA 76187	Mylan	12	Marketed
Jul 24, 2002	SynthroidNDA 21402 · New formulation or manufacturer	Abbvie	13	Marketed
Oct 24, 2002	Thyro-TabsNDA 21116 · New formulation or manufacturer	Alvogen	10	Marketed
Jun 6, 2003	LevoletNDA 21137 · New formulation or manufacturer	Genus Lifesciences	4	Marketed
Jun 23, 2004	Levothyroxine SodiumANDA 76764	Mylan	0	Discontinued
Jun 16, 2005	Levothyroxine SodiumANDA 76752	Merck Kgaa	2	Discontinued
Oct 13, 2006	TirosintNDA 21924 · New dosage form	Ibsa	7	Marketed
Jun 24, 2011	Levothyroxine SodiumNDA 202231 · TYPE 7	Fresenius Kabi USA	6	Marketed
Dec 7, 2015	Levothyroxine SodiumANDA 205366	Ph Health	0	Discontinued
Jun 29, 2016	Levothyroxine SodiumANDA 206163	Piramal Critical	0	Discontinued
Dec 15, 2016	Tirosint-SolNDA 206977 · New dosage form	Ibsa	4	Marketed
Dec 21, 2018	Levothyroxine SodiumANDA 208749	Maia Pharms Inc	0	Marketed
Jan 18, 2019	Levothyroxine SodiumANDA 209713	Lupin	4	Marketed
Feb 19, 2019	Levothyroxine SodiumANDA 210831	Amneal	3	Discontinued
Apr 11, 2019	Levothyroxine SodiumNDA 210632 · New dosage form	Fresenius Kabi USA	0	Marketed
Mar 27, 2020	Levothyroxine SodiumANDA 208837	Dr Reddys	0	Discontinued
Oct 19, 2020	Levothyroxine SodiumANDA 212399	Accord Hlthcare	5	Marketed
Oct 28, 2020	Levothyroxine SodiumANDA 211369	Ani Pharms	1	Discontinued
Nov 30, 2020	ThyquidityNDA 214047 · New formulation or manufacturer	Stevens J	0	Marketed
Jan 6, 2021	Levothyroxine SodiumANDA 213256	Ani Pharms	0	Discontinued
May 17, 2021	Levothyroxine SodiumNDA 214253 · New formulation or manufacturer	Hikma	0	Discontinued
Apr 29, 2022	ErmezaNDA 215809 · New formulation or manufacturer	Mylan	0	Discontinued
May 10, 2022	Levothyroxine SodiumANDA 207588	Watson Labs Teva	2	Marketed
Dec 21, 2022	Levothyroxine SodiumANDA 211417	Macleods Pharms	1	Marketed
Jan 18, 2023	Levothyroxine SodiumANDA 215259	Ascent Pharms Inc	0	Marketed
Mar 24, 2023	Levothyroxine SodiumANDA 217066	Zydus Pharms	0	Marketed
Jul 16, 2024	Levothyroxine SodiumANDA 216414	Aurobindo Pharma	0	Discontinued
Nov 29, 2024	Levothyroxine SodiumANDA 217495	Xiromed	0	Marketed
Mar 5, 2025	Levothyroxine SodiumANDA 216729	Onesource Specialty	0	Marketed
May 20, 2026	Levothyroxine SodiumANDA 216370	Alembic	0	Marketed

Applications, approvals and products come from FDA's Drugs@FDA data files, refreshed weekly, grouped by active ingredient as FDA spells it. Complete response letters are FDA's published letters. Medicare spending is CMS's Part D and Part B dashboard, matched to this ingredient by generic name; shortages are FDA's shortage list, matched by application number; clinical trials are ClinicalTrials.gov studies naming the ingredient as an intervention, refreshed daily; safety programs are FDA's REMS list, matched by application number or, for shared programs, by ingredient. Drugs@FDA