Tizanidine (hydrochloride)

Tizanidine hydrochloride, a skeletal muscle relaxant, is an orally effective central α₂-adrenoceptor agonist (IC₅₀ = 6.9 nmol). Tizanidine hydrochloride primarily exerts muscle relaxation effects by inhibiting the release of excitatory amino acids (glutamate and aspartate) from the presynaptic terminals of spinal cord interneurons. Tizanidine hydrochloride has anti-injury activity and can inhibit gastrointestinal (GI) transport. Tizanidine hydrochloride can inhibit the proliferation, migration, and invasion of lung cancer cells and induce cell apoptosis by upregulating Nischarin and inhibiting the AKT and Wnt3a/β-catenin signaling pathways. Tizanidine hydrochloride can be used to treat spasticity caused by diseases such as multiple sclerosis (MS), stroke, and spinal cord injury (SCI)^[1][2][3][4]. In Vitro:Tizanidine hydrochloride is mainly metabolized by cytochrome CYP1A2 and resultes in time- and NADPH-dependent substrate consumption with a half-life of 50 min in human liver microsomes^[2].
Tizanidine hydrochloride (20 μM, 0-72 h) inhibits the proliferation, migration and invasion of A549 cells, and induces apoptosis through the regulation of AKT and Wnt3a/β-catenin pathways mediated by Nischarin^[3].
In Vivo:Tizanidine (0.02-20 mg/kg, p.o., single dose or for 14 days) hydrochloride demonstrates a stronger analgesic effect in female rats with neuropathic pain and estrogen is identified as the key factor contributing to the gender difference^[4].