Baclofen Side Effects

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 immediately if any of the following side effects occur:

Less common or rare

  1. Bloody or dark urine
  2. chest pain
  3. clumsiness, unsteadiness, trembling, or other problems with muscle control
  4. fainting
  5. false sense of well-being
  6. mental depression or other mood changes
  7. pounding heartbeat
  8. ringing or buzzing in the ears
  9. seeing or hearing things that are not there
  10. skin rash or itching
  11. slurred speech or other speech problems
  12. swelling of the ankles
  13. unexplained muscle stiffness
  14. unusual excitement

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

  1. Blurred vision
  2. dizziness
  3. drowsiness
  4. irregular, fast or slow, or shallow breathing
  5. lightheadedness
  6. loss of strength or energy
  7. muscle pain or weakness
  8. pale or blue lips, fingernails, or skin
  9. seizures
  10. sleepiness or unusual drowsiness
  11. trouble breathing
  12. unusual weak feeling

Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Confusion
  2. constipation
  3. dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  4. headache
  5. increased need to urinate
  6. nausea
  7. passing urine more often
  8. sweating
  9. trouble sleeping
  10. unusual tiredness or weakness

Less common or rare

  1. Diarrhea
  2. loss of appetite
  3. muscle or joint pain
  4. numbness or tingling in the hands or feet
  5. stomach pain or discomfort
  6. stuffy nose
  7. weight gain

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

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.