NW Regional Spinal Cord Injury System University of Washington UW Rehab Medicine Go to home page

UW Medicine Harborview Medical Center

© 2024 University of Washington

follow us on twitter

follow us on facebook

Watch us on YouTube

Watch us on Vimeo

SCI Forum Report & Video


Intrathecal Baclofen Therapy for Spasticity

What is intrathecal baclofen therapy, and how does it fit into the spectrum of spasticity management options for individuals with spinal cord injury? In this SCI Forum, Rina Reyes, MD, Medical Director, UW Medicine SCI Rehabilitation Program and Assistant Professor, UW Department of Rehabilitation Medicine, provided in-depth information about when to consider an implanted, programmable baclofen pump for spasticity management; the process of being evaluated for this treatment; the potential advantages, limitations, and drawbacks to the pump; and requirements to maintain a baclofen pump.

 In addition, a panel of individuals (two with spinal cord injury and one with MS) who have implanted baclofen pumps discussed their reasons for choosing the device and what the experience has been like for them. Presented on January 12, 2010 at the University of Washington Medical Center. Read the report or watch the video on this page.

Presentation time: 85 minutes. After watching, please complete our two-minute survey. Thank you!


You can also watch this video on YouTube with or without closed-captioning.

For a complete list of our videos, click here.



Intrathecal Baclofen Therapy for Spasticity

By Rina Reyes, Medical Director, UW Medicine SCI Rehabilitation and UWMC Rehabilitation Intrathecal Baclofen Program


Table of Contents

What is the intrathecal baclofen pump?

The intrathecal baclofen pump is a surgically implanted system used to control spasticity by infusing baclofen directly into the spinal canal and around the spinal cord. (See Figure 1.)

Spasticity overview

Spasticity is the uncontrolled reflex-type contraction (tightening) of the muscles that occurs in individuals who have had an injury to the brain or spinal cord. The contractions can cause involuntary jerking and difficulty relaxing, coordinating or controlling movement. Spasticity is often triggered by ordinary activities such as stretching, changing positions, or even just a touch. The symptoms and severity of spasticity vary widely from person to person, even with the same type or level of injury.

Spasticity can have beneficial or negative effects on function; sometimes the effects are a mixture of both. Benefits include increased or preserved muscle tone, improved circulation, and even enabling you to stand, transfer or empty your bladder. On the other hand, spasms can be painful or so strong that they interfere with transfers, seating, sleeping, or performing daily activities.

In deciding whether or how to treat your spasticity, ask yourself:

Generally it is a good idea to treat spasticity if it is causing these problems:

Spasticity occurs in up to 78% of people with SCI, and 49% or more require treatment of some kind.

[Back to Table of Contents]

Treatments for Spasticity


Non-pharmacologic methods (those other than medications)

The advantage to these non-pharmacologic measures is that they have minimal side effects and can be used in addition to medications. These work well in reducing spasticity for some people, but not for others. For some, these measures are not sufficient to control the muscle tightness or spasms to the extent they desire.

Pharmacologic methods (medications)

Focal (localized) treatments
Sometimes nerve blocks or injections of anesthetics, alcohol or phenol, or neurotoxins such as botulinum toxin (Botox, Myobloc, Dysport) are used if spasticity that requires treatment is limited to one or a small area of the body.

Oral medications
People with SCI usually have more extensive spasticity, however, so oral medications are often needed. Examples of these medications include baclofen, tizanidine, clonidine, benzodiazepines such as diazepam or clonazipam, gabapentin and dantrolene.

Although these oral medications are very effective in treating spasticity, they have several disadvantages:

What method should you try? Considerations:

[Back to Table of Contents]

Intrathecal baclofen therapy

The intrathecal baclofen pump was created to solve the problems and side effects of taking oral spasticity medications. This system delivers baclofen directly to where it is needed—into the intrathecal space inside the spinal canal that contains the fluid that bathes the spinal cord. (See Figure 1.)

Figure 1: Intrathecal Baclofen Pump
(Photo credit: Medtronic)

Image showing placement of pump and catheter into spine

Key advantages


How does it work?

[Back to Table of Contents]

What does it take to maintain a pump?

You must visit your physician or pump manager regularly to have the pump refilled with baclofen before it runs out. The frequency of the refills will depend on which drug concentration is used, the daily dose that's required and the pump size. It's similar to gas your car. You can only have so much in the system, so it needs to be refilled periodically; and how often it needs to be refilled just depends on your use.

There are two pump sizes, a 20 ML and a 40 ML. We encourage the larger size if possible so you won’t need to refill it as frequently. Your provider should help with considering which size is likely to work best for you.

FDA regulations require that you get the pump refilled at least every six months, even if your pump is not yet empty. Refill frequency varies between 1 and 6 months.

You may need to get the dose or pattern of infusion adjusted periodically, especially when you first start with the pump.  When a pump is newly placed, some people find the ideal dose quickly, but many will take several weeks or months to find the right dose and infusion pattern.

When to get your pump checked


After about 5 to 7 years, your pump will need to be replaced with another surgery.  Unless there is a problem with the catheter system, the catheter will not require replacement, and the section near the pump will be simply reconnected to the new pump.

[Back to Table of Contents]

When is intrathecal baclofen therapy a good option?


Disadvantages, considerations, and complications

[Back to Table of Contents]

The process of getting an intrathecal baclofen  pump


Patient selection

Screening test


Location: Typically the pump goes in the lower abdomen on either the right or the left side. Exact location will depend on factors such as whether you have sensitivity in certain areas of the abdomen, where your belt or other clothing will lay against your skin, whether you have any ostomies, and details about your seating position.

Implantation: The catheter is inserted into the spine in the lower back, through the bones of the spinal canal and threaded into the intrathecal space. The other end of the catheter is threaded underneath the skin to the pump, which is placed under the skin of the lower abdomen.  

Dosing: The initial dose is programmed at the time of the implantation and adjusted over your hospital stay as needed. Dosing varies enormously from person to person and is not related to level of injury or body size. It may take up to several months of little adjustments before achieving the correct dose. Make sure you continue taking your oral medications even after the pump is implanted and to wean off of them gradually with guidance from your provider.

[Back to Table of Contents]

Problems to watch for

Baclofen withdrawal
Classic symptoms of baclofen withdrawal are a sudden increase or return of your spasticity or tone, profuse sweating, and itching without an associated rash. You can also have fever, high heart or respiratory rate, high or low blood pressure or even confusion. Severe withdrawal symptoms include hallucinations or delirium, seizures, rhabdomyolysis (where you actually start to breakdown muscle), organ failure and even death. Know the signs of baclofen withdrawal and contact your provider right away even with mild withdrawal symptoms to avoid progressing to severe withdrawal.

Causes of withdrawal include the pump running empty; programming error; incorrect baclofen concentration; a problem with the catheter system; and a problem with the battery. Some of these problems will activate the alarm.

Treatment for withdrawal is to resume baclofen infusion (or oral medication as a substitute) as soon as possible. If you find yourself in an emergency room and need something urgently, IV diazepam is a good option.

Preventing baclofen withdrawal

Baclofen Overdose
This is far less common than withdrawal. Mild symptoms include low muscle tone and difficulty concentrating, sleepiness or lightheadedness. Moderate symptoms are slowed heart rate, respiratory depression (slowed breathing), difficulty awakening or staying alert. Severe symptoms are low muscle tone spreading to trunk, arms, face and neck; stupor/coma; seizures; severely slowed breathing that needs mechanical ventilation, and death.

Possible causes of overdose are human error in dosing, programming or filling the pump; system malfunction; or unsafe combination of intrathecal and oral medications. Most of the time, mild overdose symptoms can be easily managed by turning the pump rate of infusion down.

Restrictions if you have intrathecal baclofen

[Back to Table of Contents]

What every person with a baclofen pump and their caregiver should know:

Getting the outcome you desire from intrathecal baclofen therapy.

  1. Know yourself and your spasticity— triggers, patterns, what seems to help, and what options you have tried in the past.
  1. You need to have clearly stated goals for spasticity reduction that include a functional improvement of some kind, such as increasing your range of motion, making personal care easier, or reducing side effects of (or the need for) oral medications. Talk to your provider to determine whether these goals can be realistically achieved with this treatment.
  1. Know the potential risks and how to respond to problems. 
  1. Be realistic about your ability and motivation to participate in all maintenance requirements over the long term.
  1. Shop for a pump provider who has a lot of experience implanting and troubleshooting these systems.
  1. Make sure the management philosophy, style and availability of the pump manager is what you expect and are comfortable with.

[Back to Table of Contents]