Muscle Spasticity

2 medicines

Muscle spasticity causes persistent stiffness and involuntary spasms after neurological injury or disease, treated with oral muscle relaxants such as baclofen and tizanidine.

Fleqsuvy

Baclofen

200ml

Fleqsuvy is a painkillers medication containing Baclofen, available as 200ml bottles.

from $34.00 / bottle View

Zanaflex

Tizanidine

2/4mg

Zanaflex is a painkillers medication containing Tizanidine, available as 2/4mg tablets.

from $0.79 / tablet View

Key facts

  • Muscle spasticity is a state of continuous or intermittent muscle stiffness that makes controlled movement difficult, caused by the nervous system losing normal inhibitory control over muscle tone.
  • It is most common in people living with multiple sclerosis, spinal cord injury, stroke, or cerebral palsy, where damaged nerve pathways let muscles contract beyond what any movement requires.
  • Oral muscle relaxants are the backbone of treatment: baclofen acts on the spinal cord to reduce excitatory signalling, while tizanidine works through a different pathway with a somewhat shorter duration of action.
  • Stretching and regular physiotherapy remain important alongside any medicine, helping prevent contractures where muscles shorten permanently from prolonged high tone.

What drives the stiffness

In a healthy nervous system, signals from the brain and spinal cord constantly regulate how much tension a muscle holds. Damage to those pathways, whether from a stroke, a spinal cord lesion, or a progressive disease like MS, disrupts that balance. The muscle receives too little inhibition and too much excitation, so it contracts beyond what any movement requires. The result ranges from mild tightness that slows movement to severe spasms that cause pain and interfere with sleep or daily care.

Managing muscle spasticity

Treatment works to reduce tone and spasm frequency without sacrificing the residual strength many people rely on for standing or walking. Oral muscle relaxants are the backbone of management. Baclofen acts directly on the spinal cord to reduce excitatory signalling, while tizanidine works through a different pathway to lower muscle tone, with a somewhat shorter duration of action. Both sit within the broader painkillers approach used for spasticity alongside physiotherapy and stretching programmes. Consistent daily movement helps prevent contractures, where muscles shorten permanently from prolonged high tone.

When to see a doctor

If spasticity suddenly worsens without an obvious cause, seek medical review promptly. It can signal a new underlying problem such as a pressure sore, urinary tract infection, or progression of the underlying disease.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.