Comparison of Safety and Efficacy of Tizanidine Hydrochloride Capsules Versus Zanaflex® (Tizanidine Hydrochloride Tablets) Taken While in the Fed State (Just After a Meal) and in the Fasted State (Before a Meal) in Patients With Moderate to Severe Spasticity.

Treatment tested

• Tizanidine

Inclusion Criteria: * IRB approved ICF must be signed and dated by patient or patient's legal representative * Male or Female 18 years of age or older * Clinical diagnosis of established spasticity (at least 3 months) secondary to multiple sclerosis, stroke, or spinal cord injury * Currently on stable dose of up to 36mg of Zanaflex * Must be able to swallow tablets or capsules whole Exclusion Criteria: * Patients with dementia, aphasia, or other deficits in cognition * Unwilling or unable to complete cognition test or daily diary * Known sensitivity to Zanaflex * Taking Zanaflex on an as needed ("prn") basis * Currently being treated with drugs having significant effects at the alpha2 receptors whether agonist (i.e., clonidine, methyldopa) or antagonist (i.e., phenothiazines, imipramine) * Currently on any other muscle relaxant or any drugs having muscle relaxant properties (including baclofen, dantrolene, diazepam and other benzodiazepines, tranquilizers, narcotic analgesics, high dose neuroleptics, chlormezanone, meprobamate, methocarbamol, orphenadrine, carisoprodol, gabapentin and clonidine * Taking any over-the-counter or prescription sleep aids within 30 days prior to screening * Use of illegal drugs or legal drugs for recreational purposes or excessive use of alcohol * Patients suffering from disabling, symptomatic hypotension (i.e., syncope) * Patients having any systemic disease such as renal insufficiency, clinically relevant elevations in hepatic transaminase, severe, uncontrolled systemic hypertension * Any clinically significant illnesses, within four weeks of screening * Patients with known sleep disorders * Patients who participated in a clinical trial within thiry days prior to screening * Women of childbearing potential who are pregnant, have a positive serum pregnancy test, lactating, or do not or will not take adequate contraceptive precautions for the duration of trial

This study is being conducted to compare the impact of somnolence (sleepiness) on cognition (awareness) as well as the safety and effectiveness of tizanidine hydrochloride capsules versus Zanaflex® (tizanidine hydrochloride tablets) taken while in the fed state (just after a meal) and in the fasted state (before a meal) in patients with moderate to severe spasticity.