Baclofen (Intrathecal)

Intrathecal baclofen is used to help relax certain muscles in your body, relieving muscle tightness caused by medical conditions such as multiple sclerosis or cerebral palsy.


Intrathecal baclofen is used to help relax certain muscles in your body, relieving cramping, spasms, and muscle tightness associated with medical problems such as cerebral palsy, multiple sclerosis, or other spinal injuries. Intrathecal baclofen treats these symptoms, but is not a cure. Your doctor may recommend additional treatment, such as physical therapy, to help improve your condition. Intrathecal baclofen works by acting on the central nervous system (CNS) to produce muscle relaxant effects, which can potentially cause some of the side effects of this medication.

Usually, your muscles receive electrical signals from your nerves that tell them when to relax and when to tense. However, in patients with spasticity, or similar conditions, these signals become uneven and it's typically because the nerves have been damaged, which causes the muscles to tense up when you don't want them to. Baclofen restores the normal signals and helps you move your muscles more easily, as well as more normally. Intrathecal baclofen is delivered by a drug pump that flows directly into the spinal fluid in your back. It's typically only given under the direction of a licensed healthcare professional, or under the supervision of one--and only after oral baclofen has proved to be futile, or more damaging.

Condition(s) Treated

Muscle spasms caused by:

  • Multiple Sclerosis
  • Cerebral Palsy
  • Other Spinal Injuries/Diseases

Type of Medicine

  • Antispastic agent

Side Effects

Certain medications can cause some unwelcome side effects. Not all of these side effects will occur in all patients, but if they do occur, they may require immediate medical attention. More common side effects of this nature include convulsions (seizures). Less common or rare side effects of this nature include:

  • Blurred vision or double vision
  • Fainting
  • Mental depression
  • Muscle weakness
  • Ringing or buzzing in the ears
  • Hearing, seeing, or feeling things that aren't there
  • Troubled breathing or shortness of breath

Symptoms of an overdose include:

  • Convulsions (seizures)
  • Drowsiness, dizziness, or lightheadedness
  • Increased watering of the mouth
  • Mental confusion
  • Muscle weakness
  • Nausea and/or vomiting
  • Shortness of breath or troubled breathing

Some side effects that occur do not require immediate medical attention. Typically, these side effects tend to go away on their own, as your body adjusts to the medication. Your doctor may be able to help you find ways to reduce or prevent some of these side effects. Talk to your doctor if any of the following side effects become bothersome or last too long--or if you have any questions about them. Some of the more common side effects include:

  • Constipation
  • Difficulty urinating
  • Dizziness
  • Headache
  • Nausea and/or vomiting
  • Tingling or numbness in hands or feet
  • Sleepiness

Less common side effects of this nature include:

  • Unsteadiness, clumsiness, trembling, or other problems with muscle control
  • Diarrhea
  • Difficulty sleeping
  • Lightheadedness or dizziness, especially when standing up from a lying or sitting position
  • Dry mouth
  • Frequent urge to urinate
  • Irritation of the skin at the site where the pump is located
  • Itching of the skin
  • Sexual problems
  • Slurred speech or other speech problems
  • Swelling of the feet, ankles, or lower legs
  • Shaking or trembling

After you stop taking baclofen, it can still cause side effects to occur that may require medical attention. Check with your doctor during this time if you notice any side effects not listed. Some side effects may occur in some patients and not others.


The dosage will vary from patient to patient. Follow all directions provided by your doctor or the directions on the label. The following information is a general guideline for how the medication should be taken. Do not change your dose unless your doctor tells you to do so.

The amount of medication you take will depend on the strength. The number of doses you take per day, the length of time you take the medication and the time allowed between doses is all determined by the medical problem you're treating.

Intrathecal baclofen is given by injection into the space around the spinal cord. It's given using a drug pump implanted under your skin by a medical professional, who will also fill and refill the pump with medication periodically. The pump is made of a catheter (a small tube) and a pump. The surgeon puts the device under the skin of your belly near your waistline. The device is usually a round, metal disc about three inches around and one inch thick.

If you're taking this medication alone at home, be sure to learn the proper preparation and usage instructions your doctor or healthcare professional provides. Prior to using this medication, check the product for particles or discoloration. If you notice either, do not use the liquid. Be sure you're properly storing any medical supplies, as well as the medication itself.

Avoid using this medication for long periods of time, as it may have adverse reactions, or it might not work well. Tell your doctor if the medication suddenly stops working well. Also, talk to your doctor if your condition does not improve, or if you have signs of an infection (e.g., fever, chills, pain/swelling/redness/warmth at the pump site).

For cerebral spasticity, adults must show a positive response to an Intrathecal test dose during the initial test phase. The test first dose will be 50 mcg (in a volume of 1 mL) injected into the pump over at least one minute. The patient will be observed for 4 to 8 hours for a positive response. The second test dose will be 75 mcg (1.5 mL) administered 24 hours after the first test dose. The third test dose will be 100 mcg (2 mL) administered 24 hours after the second test dose.


Certain medications should not be used simultaneously, however, in some cases, it may be necessary, even if an interaction may occur. In this case, your doctor might want to change the dosage of your medication, or other precautions might be taken to ensure you're safe while taking this medication with other medications. Tell your doctor if you're taking any of the medications listed below before starting baclofen.

  • Alfentanil
  • Anileridine
  • Bromazepam
  • Buprenorphine
  • Butorphanol
  • Codeine
  • Dihydrocodeine
  • Donepezil
  • Doxylamine
  • Fentanyl
  • Flibanserin
  • Hydrocodone
  • Hydromorphone
  • Levorphanol
  • Meperidine
  • Methadone
  • Morphine
  • Mophine Sulfate Liposome
  • Oxycodone
  • Oxymorphone
  • Pentazocine
  • Periciazine
  • Propoxyphene
  • Remifentanil
  • Sodium Oxybate
  • Sufentanil
  • Tapentadol
  • Tramadol
  • Zolpidem

Certain medications can also interact with food, tobacco, or alcohol. Talk to your doctor about your use of tobacco and alcohol while taking this medication, as well as the foods you regularly eat.

Some medical conditions can also affect the use of baclofen. Tell your doctor immediately if you have any medical problems like the ones listed below, especially:

  • Difficulty breathing
  • Stroke or other brain disease
  • Communication difficulties
  • Spinal cord injuries (at or above T-6)
  • History or withdrawal symptoms
  • Epilepsy
  • Kidney disease
  • Emotional or mental problems
  • Spinal lesions
  • Parkinson's disease

Having any of these conditions prior to taking baclofen can make certain conditions worse, such as Parkinson's or stoke. Some of these conditions can make side effects worse or increase your risk of getting them.


Before taking baclofen, talk to your doctor about the potential risks of the medication and determine whether the risks are worth the good the medication will do.

Tell your doctor if you have any allergic reactions to this medication or any other medications. Also, inform your doctor if you have allergies to anything else, including foods, animals, dyes or preservatives. Read the label or package ingredients carefully on nonprescription medications to be sure you're not taking anything you're allergic to.

This medication may not be safe for children under 4 years old. If you think you may be pregnant, tell your doctor immediately. Breastfeeding women should also take caution while taking this medication, as this medication may pose a small risk to the baby when it passes through the breast milk.

Keep your regular appointments with your doctor so that he or she can check your progress. This is especially important during the first few weeks of treatment with baclofen. At this point, the dosage may change to meet your individual needs.

Make sure to keep all of your appointments to refill the pump. If it's not refilled on time, the muscle tightness may return and early withdrawal symptoms may appear. Some of these symptoms include:

  • Itching skin
  • Decreased blood pressure
  • Seizures
  • Crawling, burning, numbness, itching, pricking, "pins and needles", or tingling feeling
  • Sweating
  • Blurred vision
  • Confusion
  • Unusual weakness or tiredness
  • Faintness, dizziness, or lightheadedness when standing from a sitting or lying down position

Check with your doctor before taking Intrathecal baclofen, as this medication can add to the effects of alcohol or other CNS depressants (medications that make you drowsy or less alert). Examples of CNS depressants include antihistamines or medicine for hay fever, allergies, or colds; barbiturates; anesthetics, including some dental anesthetics; sedative, tranquilizers, or sleeping medication; medicine for seizures; prescription pain medication or narcotics; and other muscle relaxants.

Intrathecal baclofen can cause a false sense of well-being, dizziness, drowsiness, lightheadedness, clumsiness or unsteadiness, or vision problems. Be sure you know you your body will react to this medication before driving, using heavy machinery, or doing anything else that requires you to remain well-coordinated, alert, and/or able to see well.

Intrathecal baclofen can also cause dryness of the mouth. Patients have tried sugarless candy or gum to relieve this side effect. You can also try melting bits of ice in your mouth or using a saliva substitute. If your dry mouth lasts for longer than two weeks, talk to your doctor or dentist. Ongoing dryness of the mouth can increase your risk for dental disease, including fungus infections, decay, and gum disease.

Do not take baclofen if you need muscle tone for safe balance and movement during any activities. Do not suddenly stop taking this medication, as you could experience highly unpleasant withdrawal symptoms, as previously mentioned.

Using baclofen can increase your risk of developing an ovarian cyst. Talk to your doctor about what specific risks you have.

Taking baclofen with drugs that can make you tired or slow down your breathing can cause serious side effects, or death. Ask your doctor about taking a sleeping pill, prescription cough medication, narcotic pain medication, muscle relaxer, or medication for seizures, depression or anxiety. Other drugs can interfere with baclofen, such as prescription and nonprescription (over-the-counter) medications, herbal products, and vitamins. Tell your doctor about any of these types of drugs you're starting or stopping while on baclofen.


Store this medication away from moisture and heat.


Intrathecal baclofen is a greatly beneficial drug for patients suffering from muscle spasms caused by certain medical conditions, such as cerebral palsy, multiple sclerosis, and other spinal cord injuries. It works by helping to relax the muscles. Typically given to patients who cannot tolerate the side effects of or who do not respond to baclofen taken by mouth, Intrathecal baclofen

When taken correctly, Intrathecal baclofen can provide the relief of side effects and symptoms, which may have taken a toll on everyday activities in the patient's life. Whether the patient suffers from multiple sclerosis or cerebral palsy, Intrathecal baclofen can help alleviate the symptoms associated with these conditions, such as muscle spasms and tightness. This medication can help improve quality of life for patients suffering from multiple sclerosis or cerebral palsy. To achieve these results, the patient must work with the doctor to determine the most effective course of treatment.

Last Reviewed:
December 22, 2017
Last Updated:
April 02, 2018