14 Nov 2011
Zanaflex (tizanidine) shows up in your system as tizanidine and its metabolites (none of which are active). Tizanidine is extensively metabolized,
with the two major metabolites of tizanidine having been
identified as DS-200-717 (metabolite 3, guanidine, [(5-chloro-4-(2-
imidazolin-4-on-2-ylamino)-2,1,3-benzothiazdiazole] and DS-201-
341 (metabolite 4, amide, [5-chloro-4-(guanidino)-2,1,3-benzothiazdiazole]).
Pharmacokinetics, Metabolism and Excretion
Tizanidine has linear pharmacokinetics over a dose of 1 mg to 20 mg. Tizanidine has a half-life of approximately 2.5 hours (CV = 33%). Approximately 95% of an administered dose is metabolized. The primary cytochrome P450 isoenzyme involved in tizanidine metabolism is CYP1A2. Tizanidine metabolites are not known to be active; their half-lives range from 20 to 40 hours.
Search for questions
Still looking for answers? Try searching for what you seek or ask your own question.
I have been on alot of medications in the past to try and help my pain, but all of it is just to strong, I have come back to the Lortab every time, I ...
4 answers • 28 Sep 2009
2 answers • 1 Nov 2012
I have been on 4mg of Zanaflex nightly for years as a preventative medication for migraines caused by TMJ and neck and shoulder soreness and ...
2 answers • 29 Apr 2013