Tizanidine Chemische Eigenschaften,Einsatz,Produktion Methoden
R-Sätze Betriebsanweisung:
R22:Gesundheitsschädlich beim Verschlucken.
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
S-Sätze Betriebsanweisung:
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
Beschreibung
Tizanidine is a centrally-acting muscle relaxant useful in the treatment of muscle
spasms and a variety of spastic conditions.
Verwenden
Labeled Tizanidine, intended for use as an internal standard for the quantification of Tizanidine by GC- or LC-mass spectrometry.
Definition
ChEBI: 2,1,3-Benzothiadiazole substituted at C-4 by a Delta1-imidazolin-2-ylamino group and at C-4 by a chloro group. It is an agonist at alpha2-adrenergic receptor sites.
Mechanism of action
Tizanidine is a centrally active muscle relaxant analogue of clonidine that is approved for use in reducing spasticity associated with cerebral or spinal cord
injury. Its mechanism of action for reducing spasticity suggests presynaptic inhibition of motor neurons at the α2-adrenergic receptor sites, reducing the release of
excitatory amino acids and inhibiting facilitatory ceruleospinal pathways, thus resulting in a reduction in spasticity. Tizanidine only has a small fraction of the
antihypertensive action of clonidine, presumably because of action at a selective subgroup of α2C-adrenoceptors, which appear to be responsible for the analgesic and
antispasmodic activity of imidazoline α2-agonists(20).
Clinical Use
Tizanidine is a centrally acting adrenergic α2 receptor agonist used to treat chronic muscle
spasticity conditions, such as multiple sclerosis.
Nebenwirkungen
Postulated mechanisms include α2 receptor-mediated decreased release of norepinephrine and
serotonin from spinal interneurons. Tizanidine is structurally related to the α2 agonist
clonidine that is used to treat hypertension; however, the blood pressure–lowering potency of
tizanidine is approximately 10 to 20% that of clonidine. Nevertheless, patients may experience
hypotension with tizanidine, together with muscle weakness, that may result in dizziness and falls
in mobile patients. Tizanidine is rapidly and almost completely absorbed from the gastrointestinal
tract; however, the estimated bioavailability is only 10 to 15% because of extensive first-pass
metabolism, mainly by CYP1A2, which results in oxidative degradation of the imidazoline ring
and hydroxylation of the aromatic system. Elevated liver enzyme values are not frequent
with tizanidine use. Hepatic injury and death because of liver failure have been reported,
however, and this complication should be considered in view of its marginal antispasmodic
efficacy. Other frequently reported side effects of tizanidine are drowsiness and dry
mouth. Clonidine also has been used to treat spasticity; however, even less high-quality clinical
study data are available for this agent.
Tizanidine Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
