Tizanidine (trade names Zanaflex (Acorda Therapeutics), Sirdalud (Novartis), Relentus (Beximco Pharma) Is a centrally acting α₂ adrenergic agonist used as a muscle relaxant. It is used to treat the spasms, cramping, and tightness of muscles caused by medical problems such as multiple sclerosis, ALS, spastic diplegia, back pain, or certain other injuries to the spine or central nervous system. It is also prescribed off-label for migraine headaches, as a sleep aid, and as an anticonvulsant. It is also prescribed for some symptoms of fibromyalgia.^[2]

Tizanidine has been found to be as effective as other antispasmodic drugs and is more tolerable than baclofen and .^[3] Tizanidine can be very strong even at the 2 mg dose and may cause hypotension, so caution is advised when it is used in patients who have a history of orthostatic hypotension, or when switching from gel cap to tablet form and vice versa.