Chlorzoxazone

Product NDC: 45865-434
Requested package NDC: 45865-434-20
11-digit product format: 458650434
Labeler code: 45865
Product ID: 45865-434_720357e2-6f15-737d-e053-2a95a90ae54b
Type: HUMAN PRESCRIPTION DRUG
Nonproprietary name: Chlorzoxazone
Dosage form: TABLET
Route: ORAL
Labeler: Medsource Pharmaceuticals
Application: ANDA089859
Marketing category: ANDA
Marketing start: 2011-08-22
Marketing end: 0000-00-00
Substance: CHLORZOXAZONE
Active strength: 500 mg/1
Pharmacologic classes: Centrally-mediated Muscle Relaxation [PE],Muscle Relaxant [EPC]
NDC exclude flag: No
Listing certified through: 2020-12-31
Current FDA listing: Historical FDA.report record

NDC auxiliary status#

These records are reproduced from FDA’s unfinished, excluded, and compounder listings. They describe what appeared in the source files; a missing record does not establish a regulatory status. View all current auxiliary records, including entries without an NDC. · View the auxiliary file history.

Current NDC status page 1 of 1 · 1 matching rows.

Dataset, Scope, Product NDC table
Dataset	Scope	Product NDC	Package NDC	Code	Status	Reporting period	Source date
excluded package	package	45865-434	45865-434-20	I	Inactivated by FDA		2026-08-17

Observed NDC auxiliary status history#

This history shows the information present in each captured FDA auxiliary file. It is not a continuous regulatory timeline, and a missing record does not establish a status.

Historic NDC status page 1 of 1 · 9 matching rows.

View current auxiliary records. · View the auxiliary file history.

Captured / source date, Code, Status table
Captured / source date	Code	Status	Snapshot	Source SHA-256
2025-12-14 17:58 UTC · source 2025-12-05	I	Inactivated by FDA	`d630ba8d3edf…`	`732f749b63fb…`
2025-08-27 00:01 UTC · source 2025-08-26	I	Inactivated by FDA	`f5e01cc5f278…`	`a2eaf40c39c3…`
2025-04-01 02:39 UTC · source 2025-03-31	I	Inactivated by FDA	`2ef7874e63bc…`	`57b86245f4fa…`
2025-03-28 20:22 UTC · source 2025-03-28	I	Inactivated by FDA	`a1b67e2a42f9…`	`c4cf2c586c0d…`
2025-03-22 03:12 UTC · source 2025-03-21	I	Inactivated by FDA	`cfe11265f3b6…`	`090c488252e2…`
2025-03-10 12:48 UTC · source 2025-03-10	I	Inactivated by FDA	`cdf11ea48f46…`	`ba0047e9e063…`
2025-02-02 03:52 UTC · source 2025-01-31	U	Excluded because listing certification expired	`302b2466d912…`	`e7b80fea0513…`
2025-01-20 13:05 UTC · source 2025-01-20	U	Excluded because listing certification expired	`ed331223b511…`	`672a5bd82f5f…`
2025-01-11 03:41 UTC · source 2025-01-10	U	Excluded because listing certification expired	`0efc9e666f02…`	`f202fb6c5f17…`

Source provenance: Browse the complete Orange Book source catalog · source snapshot 42.

Orange Book products#

Current product rows page 1 of 1 · 1 matching rows.

Application-product, Trade name, Ingredient table
Application-product	Trade name	Ingredient	Strength	Dosage form / route	TE codes	RLD / RS	Approval date
A089859-001	CHLORZOXAZONE	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04

Therapeutic equivalence codes#

Current TE-code rows page 1 of 1 · 1 matching rows.

Application-product, TE code table
Application-product	TE code
A089859-001	AA

Observed Orange Book product history#

Observed FDA ZIP history: Each table is queried independently by exact application/product key from successfully parsed Orange Book snapshots. Capture times identify archived source observations; absence or a change between snapshots is not inferred. FDA publication files that were not recoverable as structured ZIP data are not represented as states.

Product history page 1 of 2 · 42 observed states.

Captured, Edition, Application-product table
Captured	Edition	Application-product	Trade name	Strength	Dosage form / route	Product TE source text	RLD / RS	Approval date	Source SHA-256
2026-08-18 06:07:40	2026-07	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`caaa826d4ba7…`
2026-02-19 14:30 UTC	2026-02	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`011fe1cb6892…`
2025-12-14 10:44 UTC · 2 captures of this ZIP	2025-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`31067a03dcf5…`
2025-08-23 18:47 UTC	2025-08	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`6a471c1ec25d…`
2025-03-22 03:13 UTC · 3 captures of this ZIP	2025-03	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`fd3edfee7708…`
2025-02-26 10:13 UTC · 3 captures of this ZIP	2025-02	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`b8a1b40f171c…`
2025-01-19 17:59 UTC · 7 captures of this ZIP	2025-01	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`03ed91905a0d…`
2024-12-13 21:23 UTC · 2 captures of this ZIP	2024-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`2680178bc6a6…`
2024-09-14 05:58 UTC · 2 captures of this ZIP	2024-09	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`5bbf6a4d5a75…`
2024-11-08 22:44 UTC · 3 captures of this ZIP	2024-11	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`d8e5a09893c0…`
2024-10-29 15:01 UTC	2024-10	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`d06236e962d9…`
2024-08-13 05:28 UTC · 3 captures of this ZIP	2024-08	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`79d66fd596c7…`
2024-07-13 05:37 UTC · 2 captures of this ZIP	2024-07	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`301d65b070ca…`
2024-06-18 03:08 UTC · 5 captures of this ZIP	2024-06	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`1e350fbaab3a…`
2024-05-31 18:47 UTC	2024-05	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`8072bd15b7f6…`
2022-06-29 02:47 UTC · 2 captures of this ZIP	2022-06	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`5c6f7cd8ea54…`
2022-04-08 23:34 UTC	2022-04	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`5d02ea3f76ae…`
2022-04-04 05:41 UTC	2022-04	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`4b0b4de00fa7…`
2019-12-13 00:20 UTC	2019-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`74a2ff9319b5…`
2022-03-09 01:35 UTC	2022-03	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`bb7c543d1eb4…`
2021-12-28 21:50 UTC	2021-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`782e0a99824c…`
2021-05-05 16:15 UTC · 3 captures of this ZIP	2021-05	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`87673890dc5c…`
2021-03-12 10:30 UTC	2021-03	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`5aa47cf7b7d7…`
2020-12-22 03:56 UTC	2020-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`8869cabd3fbd…`
2020-11-12 02:37 UTC	2020-11	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`c0c555d07b60…`
2019-12-14 00:12 UTC	2019-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`3f01610625f2…`
2019-09-15 20:21 UTC	2019-09	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL		RS	1988-05-04	`b00525d2431f…`
2019-07-19 19:46 UTC	2019-07	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL		RS	1988-05-04	`ea99ee380514…`
2024-03-16 18:09 UTC · 4 captures of this ZIP	2024-03	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`6a51e52b5d6a…`
2024-02-18 07:12 UTC	2024-02	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`1c564ffb4f44…`
2023-12-20 04:57 UTC	2023-12	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`ea1830bbd6c7…`
2023-11-28 05:40 UTC · 2 captures of this ZIP	2023-11	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`a72a2bbeb626…`
2023-10-25 00:34 UTC · 2 captures of this ZIP	2023-10	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`9b2671bbb829…`
2023-07-15 15:27 UTC · 2 captures of this ZIP	2023-07	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`a67488948f0b…`
2023-06-13 01:57 UTC · 3 captures of this ZIP	2023-06	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`3f0d92c62455…`
2023-05-13 08:27 UTC	2023-05	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`053a50430f4f…`
2023-01-26 05:58 UTC	2023-01	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`3bdfa0b2c4d7…`
2022-11-12 20:34 UTC · 5 captures of this ZIP	2022-11	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`3a93d1ddd44b…`
2022-10-28 04:53 UTC	2022-10	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`f41ea6bd6efb…`
2022-09-29 23:25 UTC	2022-09	A089859-001	CHLORZOXAZONE	500MG	TABLET / ORAL	AA	RS	1988-05-04	`e64feba35796…`

Observed Orange Book normalized TE history#

Captured, Edition, Application-product table
Captured	Edition	Application-product	TE code	Order	Source SHA-256
2026-08-18 06:07:40	2026-07	A089859-001	AA	1	`caaa826d4ba7…`
2026-02-19 14:30 UTC	2026-02	A089859-001	AA	1	`011fe1cb6892…`
2025-12-14 10:44 UTC · 2 captures of this ZIP	2025-12	A089859-001	AA	1	`31067a03dcf5…`
2025-08-23 18:47 UTC	2025-08	A089859-001	AA	1	`6a471c1ec25d…`
2025-03-22 03:13 UTC · 3 captures of this ZIP	2025-03	A089859-001	AA	1	`fd3edfee7708…`
2025-02-26 10:13 UTC · 3 captures of this ZIP	2025-02	A089859-001	AA	1	`b8a1b40f171c…`
2025-01-19 17:59 UTC · 7 captures of this ZIP	2025-01	A089859-001	AA	1	`03ed91905a0d…`
2024-12-13 21:23 UTC · 2 captures of this ZIP	2024-12	A089859-001	AA	1	`2680178bc6a6…`
2024-09-14 05:58 UTC · 2 captures of this ZIP	2024-09	A089859-001	AA	1	`5bbf6a4d5a75…`
2024-11-08 22:44 UTC · 3 captures of this ZIP	2024-11	A089859-001	AA	1	`d8e5a09893c0…`
2024-10-29 15:01 UTC	2024-10	A089859-001	AA	1	`d06236e962d9…`
2024-08-13 05:28 UTC · 3 captures of this ZIP	2024-08	A089859-001	AA	1	`79d66fd596c7…`
2024-07-13 05:37 UTC · 2 captures of this ZIP	2024-07	A089859-001	AA	1	`301d65b070ca…`
2024-06-18 03:08 UTC · 5 captures of this ZIP	2024-06	A089859-001	AA	1	`1e350fbaab3a…`
2024-05-31 18:47 UTC	2024-05	A089859-001	AA	1	`8072bd15b7f6…`
2022-06-29 02:47 UTC · 2 captures of this ZIP	2022-06	A089859-001	AA	1	`5c6f7cd8ea54…`
2022-04-08 23:34 UTC	2022-04	A089859-001	AA	1	`5d02ea3f76ae…`
2022-04-04 05:41 UTC	2022-04	A089859-001	AA	1	`4b0b4de00fa7…`
2019-12-13 00:20 UTC	2019-12	A089859-001	AA	1	`74a2ff9319b5…`
2022-03-09 01:35 UTC	2022-03	A089859-001	AA	1	`bb7c543d1eb4…`
2021-12-28 21:50 UTC	2021-12	A089859-001	AA	1	`782e0a99824c…`
2021-05-05 16:15 UTC · 3 captures of this ZIP	2021-05	A089859-001	AA	1	`87673890dc5c…`
2021-03-12 10:30 UTC	2021-03	A089859-001	AA	1	`5aa47cf7b7d7…`
2020-12-22 03:56 UTC	2020-12	A089859-001	AA	1	`8869cabd3fbd…`
2020-11-12 02:37 UTC	2020-11	A089859-001	AA	1	`c0c555d07b60…`
2019-12-14 00:12 UTC	2019-12	A089859-001	AA	1	`3f01610625f2…`
2024-03-16 18:09 UTC · 4 captures of this ZIP	2024-03	A089859-001	AA	1	`6a51e52b5d6a…`
2024-02-18 07:12 UTC	2024-02	A089859-001	AA	1	`1c564ffb4f44…`
2023-12-20 04:57 UTC	2023-12	A089859-001	AA	1	`ea1830bbd6c7…`
2023-11-28 05:40 UTC · 2 captures of this ZIP	2023-11	A089859-001	AA	1	`a72a2bbeb626…`
2023-10-25 00:34 UTC · 2 captures of this ZIP	2023-10	A089859-001	AA	1	`9b2671bbb829…`
2023-07-15 15:27 UTC · 2 captures of this ZIP	2023-07	A089859-001	AA	1	`a67488948f0b…`
2023-06-13 01:57 UTC · 3 captures of this ZIP	2023-06	A089859-001	AA	1	`3f0d92c62455…`
2023-05-13 08:27 UTC	2023-05	A089859-001	AA	1	`053a50430f4f…`
2023-01-26 05:58 UTC	2023-01	A089859-001	AA	1	`3bdfa0b2c4d7…`
2022-11-12 20:34 UTC · 5 captures of this ZIP	2022-11	A089859-001	AA	1	`3a93d1ddd44b…`
2022-10-28 04:53 UTC	2022-10	A089859-001	AA	1	`f41ea6bd6efb…`
2022-09-29 23:25 UTC	2022-09	A089859-001	AA	1	`e64feba35796…`
2022-07-09 03:26 UTC · 3 captures of this ZIP	2022-07	A089859-001	AA	1	`cb3db0bc1861…`
2026-07-26 02:55 UTC · 3 captures of this ZIP	2026-06	A089859-001	AA	1	`a50c72e98297…`

DailyMed Product Concepts#

Product concept, Relation, Version table
Product concept	Relation	Version	Effective
a7ba9d15-162f-2741-f0fc-3516be5e88bd	Product name	7	20250114
cbf4a4f8-16cb-4546-a0cc-fd91bbe774f2	Product name	2	20240223
0a48cfb8-244e-463e-aa85-fd9bbbc9190a	Product name	2	20200224

FDA-Initiated Inactive NDC Indexing#

NDC, Effective, Action table
NDC	Effective	Action	Document	Indexing SPL	Related label
45865-434-20	2025-01-30	C162847	48780-1	2cef2736-6b75-d83d-e063-dadaa90ab31f	Chlorzoxazone Tablets, USP 500 mg Revised: March 2015 Rx only 195609-1
45865-434-30	2025-01-30	C162847	48780-1	2cef2736-6b75-d83d-e063-dadaa90ab31f	Chlorzoxazone Tablets, USP 500 mg Revised: March 2015 Rx only 195609-1

DailyMed Package Descriptions#

Package NDC, Product, Description table
Package NDC	Product	Description	Form	Quantity	Strength	SPL version
45865-434-20	Chlorzoxazone	20 in 1 BOTTLE, PLASTIC	TABLET	20		1
45865-434-30	Chlorzoxazone	30 in 1 BOTTLE, PLASTIC	TABLET	30		1

DailyMed Dashboard NDC Coverage#

NDC, Dashboard title, SPL version table
NDC	Dashboard title	SPL version	Validation	Dashboard ZIP
45865-434	CHLORZOXAZONE TABLET [MEDSOURCE PHARMACEUTICALS]	1	Legacy NDC, 2 package rows	20180728_720357e2-6f14-737d-e053-2a95a90ae54b.zip

openFDA label cross-check#

OpenFDA label data provides additional search and identifier links. DailyMed’s Structured Product Label is the canonical label on FDA.report. Matching records are deduplicated before they are shown below.

Matched openFDA labels page 1 of 1 · 5 matching rows.

Brand, Generic, Manufacturer table
Brand	Generic	Manufacturer	SPL set ID	Effective date	Available safety fields	Join
Chlorzoxazone	CHLORZOXAZONE	PD-Rx Pharmaceuticals, Inc.	8650d342-92df-48d7-9f3d-cdd6f6f4c0e7	2025-10-20	Warnings, Adverse reactions	Exact identifier application applno (ANDA): 089859 application number: ANDA089859
Chlorzoxazone	CHLORZOXAZONE	Bryant Ranch Prepack	5e6889c9-a091-4622-0a00-ad0fc1830f78	2024-10-08	Warnings, Adverse reactions	Exact identifier application applno (ANDA): 089859 application number: ANDA089859
Chlorzoxazone	CHLORZOXAZONE	Actavis Pharma, Inc.	2f05e8e2-616f-475b-ac9f-c42e1a5dbe81	2024-08-25	Warnings, Adverse reactions	Exact identifier application applno (ANDA): 089859 application number: ANDA089859
Chlorzoxazone	CHLORZOXAZONE	A-S Medication Solutions	6c418b8f-4a1c-4611-80d5-3a3a7dbca9c8	2023-03-08	Warnings, Adverse reactions	Exact identifier application applno (ANDA): 089859 application number: ANDA089859
Chlorzoxazone	CHLORZOXAZONE	Proficient Rx LP	63338935-f3dd-4ef1-bb66-856a83c95f41	2022-04-01	Warnings, Adverse reactions	Exact identifier application applno (ANDA): 089859 application number: ANDA089859

UNII, Preferred term, Registry number table
UNII	Preferred term	Registry number	Matched term
H0DE420U8G	CHLORZOXAZONE	95-25-0	CHLORZOXAZONE

DailyMed RxNorm Mappings#

RxCUI, RxNorm string, TTY table
RxCUI	RxNorm string	TTY	DailyMed	SPL version
197502	chlorzoxazone 500 MG Oral Tablet	PSN	720357e2-6f14-737d-e053-2a95a90ae54b	1
197502	chlorzoxazone 500 MG Oral Tablet	SCD	720357e2-6f14-737d-e053-2a95a90ae54b	1

Packages#

Package NDC, 11-digit format, Description table
Package NDC	11-digit format	Description	Units	Marketing start	Marketing end	Sample	Exclude flag	Status
45865-434-20	45865043420	20 TABLET in 1 BOTTLE, PLASTIC (45865-434-20)	20 tablet	2018-01-01	0000-00-00	No	No	Current

Title, Manufacturer, Effective date table
Title	Manufacturer	Effective date	Type	Version
Chlorzoxazone Tablets, USP 500 mg Revised: March 2015 Rx only 195609-1	Medsource Pharmaceuticals	2018-07-27	HUMAN PRESCRIPTION DRUG LABEL	1