In the U.S.—

In Canada—

• Antispastic analgesic (in trigeminal neuralgia)

Baclofen (BAK-loe-fen) is used to help relax certain muscles in your body. It relieves the spasms, cramping, and tightness of muscles caused by medical problems such as multiple sclerosis or certain injuries to the spine. Baclofen does not cure these problems, but it may allow other treatment, such as physical therapy, to be more helpful in improving your condition.

Baclofen acts on the central nervous system (CNS) to produce its muscle relaxant effects. Its actions on the CNS may also cause some of the medicine's side effects. Baclofen may also be used to relieve other conditions as determined by your doctor.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For baclofen, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to baclofen. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Studies on birth defects with baclofen have not been done in humans. However, studies in animals have shown that baclofen, when given in doses several times the human dose, increases the chance of hernias and incomplete or slow development of bones in the fetus, and of lower birth weight.

Breast-feeding—Baclofen passes into the breast milk. However, this medicine has not been reported to cause problems in nursing babies.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of baclofen in children with use in other age groups.

Older adults—Side effects such as hallucinations, confusion or mental depression, other mood or mental changes, and severe drowsiness may be especially likely to occur in elderly patients, who are usually more sensitive than younger adults to the effects of baclofen.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking baclofen, it is especially important that your health care professional know if you are taking any of the following:

• Antidepressants, tricyclic (amitriptyline [e.g., Elavil]), amoxapine [e.g., Asendin], clomipramine [e.g., Anafranil], desipramine [e.g., Pertofrane], doxepin [e.g., Sinequan], imipramine [e.g., Tofranil], nortriptyline [e.g., Aventyl], protriptyline [e.g., Vivactil], trimipramine [e.g., Surmontil]) or
• Central nervous system (CNS) depressants (medicines that causes drowsiness)—The chance of side effects may be increased

• Diabetes mellitus (sugar diabetes)—Baclofen may raise blood sugar levels

• Epilepsy or
• Kidney disease or
• Mental or emotional problems or
• Stroke or other brain disease—The chance of side effects may be increased

Dosing—

The dose of baclofen will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of baclofen. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage form (tablets):
  • For muscle relaxation:
    • Adults and teenagers—At first, the dose is 5 milligrams (mg) three times a day. Then, each dose may be increased by 5 mg every three days until the desired response is reached. No more than 80 mg should be taken within a twenty-four-hour period.
    • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, and you remember within an hour or so of the missed dose, take it as soon as you remember. However, if you do not remember until later, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Do not suddenly stop taking this medicine. Unwanted effects may occur if the medicine is stopped suddenly. Check with your doctor for the best way to reduce gradually the amount you are taking before stopping completely.

This medicine will add to the effects of alcohol and other CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; other muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are using baclofen.

This medicine may cause drowsiness, dizziness, vision problems, or clumsiness or unsteadiness in some people. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert, well-coordinated, and able to see well.

For diabetic patients:

• This medicine may cause your blood sugar levels to rise. If you notice a change in the results of your blood or urine sugar test or if you have any questions about this, check with your doctor.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• Less common or rare
  • Bloody or dark urine;  chest pain;  fainting;  hallucinations (seeing or hearing things that are not there);  mental depression or other mood changes;  ringing or buzzing in the ears;  skin rash or itching 
  
  

• Symptoms of overdose
  • Blurred or double vision;  convulsions (seizures);  muscle weakness (severe);  shortness of breath or unusually slow or troubled breathing;  vomiting 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Confusion;  dizziness or lightheadedness ;  drowsiness;  nausea;  unusual weakness, especially muscle weakness 
  
  

• Less common or rare
  • Abdominal or stomach pain or discomfort;  clumsiness, unsteadiness, trembling, or other problems with muscle control ;  constipation;  diarrhea ;  difficult or painful urination or decrease in amount of urine;  false sense of well-being;  frequent urge to urinate or uncontrolled urination;  headache;  loss of appetite;  low blood pressure;  muscle or joint pain;  numbness or tingling in hands or feet;  pounding heartbeat;  sexual problems in males;  slurred speech or other speech problems ;  stuffy nose;  swelling of ankles;  trouble in sleeping;  unexplained muscle stiffness;  unusual excitement ;  unusual tiredness;  weight gain 
  
  

Some side effects may occur after you have stopped taking this medicine, especially if you stop taking it suddenly. Check with your doctor immediately if any of the following effects occur:

• Convulsions (seizures);  hallucinations (seeing or hearing things that are not there);  increase in muscle spasm, cramping, or tightness;  mood or mental changes;  unusual nervousness or restlessness  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although this use is not included in product labeling, baclofen is used in certain patients with trigeminal neuralgia (severe burning or stabbing pain along the nerves in the face); also called ''tic douloureux.''

There is no additional information relating to proper use, precautions, or side effects for this use of baclofen.