Zanaflex

Manages spasticity. NDA 20397, held by Legacy. Tizanidine Hydrochloride.

As of Nov 13, 2026, NDA 20397 (Zanaflex), held by Legacy, was first approved by FDA on Nov 27, 1996, with 20 approved supplements and 0 published complete response letters.

First approved: Nov 27, 1996
Review: Standard
Supplements approved: 20
Complete response letters: 0

What It's For

From the FDA-approved label (Indications and Usage)

Zanaflex is indicated for the management of spasticity. Because of the short duration of therapeutic effect, treatment with Zanaflex should be reserved for those daily activities and times when relief of spasticity is most important.

Full prescribing information on DailyMed ↗

Approvals and New Uses

The original application and every efficacy supplement, newest first; all 21 submissions below

Date	Submission	Status	Documents
Nov 27, 1996	Original applicationNew molecular entity · Standard review	Approved	Review

Products

2 strengths and forms

Product	Active ingredient	Marketing
ZanaflexEQ 4MG BASE · tablet;oral	Tizanidine Hydrochloride	RxReference drug
ZanaflexEQ 2MG BASE Federal Register determination that product was not discontinued or withdrawn for safety or effectiveness reasons · tablet;oral	Tizanidine Hydrochloride	DiscontinuedReference drug

All 21 submissions, including labeling and manufacturing supplements

Date	Submission	Status	Documents
Nov 22, 2024	Supplement 29Labeling · Standard review	Approved	Label Letter
May 31, 2024	Supplement 28Labeling · Standard review	Approved	Label Letter
May 27, 2016	Supplement 25Manufacturing · Standard review	Approved	None posted
Nov 7, 2013	Supplement 26Labeling	Approved	Label Letter
Mar 19, 2013	Supplement 23Labeling · Standard review	Approved	Letter
Jul 28, 2006	Supplement 21Labeling · Standard review	Approved	Letter Label
Nov 27, 2002	Supplement 14Labeling · Standard review	Approved	Letter
May 17, 2002	Supplement 16Manufacturing · Standard review	Approved	None posted
Apr 10, 2002	Supplement 15Manufacturing · Standard review	Approved	None posted
Aug 22, 2001	Supplement 13Manufacturing · Standard review	Approved	None posted
Aug 21, 2001	Supplement 12Manufacturing · Standard review	Approved	None posted
Mar 20, 2001	Supplement 11Manufacturing · Standard review	Approved	None posted
Dec 7, 2000	Supplement 10Manufacturing · Standard review	Approved	None posted
Aug 21, 2000	Supplement 8Manufacturing · Standard review	Approved	None posted
Jun 26, 2000	Supplement 7Manufacturing · Standard review	Approved	None posted
Feb 4, 2000	Supplement 4Manufacturing · Standard review	Approved	Review
Jun 15, 1999	Supplement 5Manufacturing · Standard review	Approved	None posted
Oct 23, 1997	Supplement 3Manufacturing · Standard review	Approved	None posted
Sep 2, 1997	Supplement 2Manufacturing · Standard review	Approved	None posted
Sep 2, 1997	Supplement 1Manufacturing · Standard review	Approved	None posted
Nov 27, 1996	Original applicationNew molecular entity · Standard review	Approved	Review

Identifiers

Application: NDA 20397
Drugs@FDA: Overview at FDA
Company: LEGACY

Approvals, supplements, products and documents come from FDA's Drugs@FDA data files, refreshed daily; Drugs@FDA lists approved applications only. Complete response letters are FDA's published letters. Drugs@FDA and FDA complete response letters