Acebutolol
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Drug reference
Tizanidine
Muscle Relaxant
Muscle RelaxantATC M03BX10
CDSCO approvedSchedule HATC M03BX10
EXCRETION
—
not curated
INTERACTIONS
12 major
SEVERE in our sources
PREGNANCY
—
not curated
Top interactionssee all 12 →
- AcebutololSevereDatabaseDDInter
- AcyclovirSevereDatabaseDDInter
- AldesleukinSevereDatabaseDDInter
- AlfentanilSevereDatabaseDDInter
Mechanism
Tizanidine is a centrally acting alpha-2 adrenergic agonist structurally related to clonidine that reduces spasticity by enhancing presynaptic inhibition of spinal motor neurons. It acts primarily in the spinal cord, increasing inhibitory neurotransmission at alpha-2 receptors on spinal interneurons, which reduces the release of excitatory amino acids (aspartate, glutamate) and suppresses polysynaptic reflexes. Unlike dantrolene (which acts peripherally on muscle), tizanidine's central mechanism does not cause generalized muscle weakness.
Indications
Muscle cramps (off-label)Muscle stiffness (off-label)Spasticity (off-label)Increased muscle tone (off-label)Spasticity in multiple sclerosis (off-label)Spasticity due to multiple sclerosisSpasticity due to spinal cord injuryspasticity associated with cerebral and spinal disordersSpasticity in multiple sclerosisSpasticity after strokeMay be effective in patients with ALSspasticity due to neurological disorderspainful muscle spasms of spinal origin
Dosing
- Adult
- 16 Guidance on intravenous infusions
Pharmacokinetics
Half-life
Short
Metabolism
undergoes first pass metabolism
Excretion
excreted by the kidney
Contraindications
- patients receiving antihypertensives, especially clonidine
Side effects
Common
XerostomiaDizzinessSedationDry mouthdrowsinessastheniadry-mouthnight-time insomniahallucinationsdose-dependent elevation of liver enzymes
Serious
- Rebound spasms
- Tachycardia
- Hypertension (if withdrawn rapidly)
Drug interactions
Acyclovir
Severe
Database
Drug interaction classified as: metabolism.
Source: DDInter
Aldesleukin
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Alfentanil
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Aliskiren
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Ambrisentan
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Amiloride
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Amiodarone
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Amisulpride
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Amrinone
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Amyl Nitrite
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Anagrelide
Severe
Database
Drug interaction classified as: metabolism
Source: DDInter
Related guidelines
Other Muscle Relaxant drugs
Ask House about Tizanidine
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Sources: KD Tripathi 7e, Goodman & Gilman 14e, BNF·Verified: 2026-05-10 · House clinical team