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Baclofen Side Effects

Medically reviewed by Drugs.com. Last updated on Oct 24, 2023.

Applies to baclofen: oral packet, oral solution, oral suspension, oral tablet. Other dosage forms:

Serious side effects of Baclofen

Along with its needed effects, baclofen 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 while taking baclofen:

Less common or rare

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

Symptoms of overdose

Other side effects of Baclofen

Some side effects of baclofen 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

Less common or rare

For Healthcare Professionals

Applies to baclofen: compounding powder, intrathecal solution, oral granule, oral liquid, oral solution, oral suspension, oral tablet.

Cardiovascular

Common (1% to 10%): Cardiac output decreased, hypotension, hypertension, diminished cardiovascular functions, peripheral edema

Rare (less than 0.1%): Arrhythmias, palpitations, chest pain

Frequency not reported: Bradycardia, orthostatic hypotension[Ref]

Dermatologic

Common (1% to 10%): Rash, hyperhidrosis, urticaria/pruritus, facial edema

Uncommon (0.1% to 1%): Alopecia, diaphoresis

Frequency not reported: Rash, sweating, contact dermatitis, skin ulcer[Ref]

Endocrine

Common (1% to 10%): Ovarian cysts are palpable in 4% of women treated with for up to one year[Ref]

Gastrointestinal

Very common (10% or more): Nausea (especially at start of therapy) (up to 11%)

Common (1% to 10%): Dry mouth, GI disorder/disturbance, constipation, diarrhea, retching, vomiting, increased salivation

Uncommon (0.1% to 1%): Dysphagia, dehydration, ileus, decreased taste sensation

Rare (less than 0.1%): Colicky abdominal pain, anorexia

Frequency not reported: GI hemorrhage[Ref]

Genitourinary

Very common (10% or more): Urinary retention (up to 12%)

Common (1% to 10%): Urinary incontinence, urination impaired, sexual dysfunction, urinary frequency, enuresis, dysuria

Rare (less than 0.1%): Erectile dysfunction

Frequency not reported: Dysuria, abnormal ejaculation, oliguria, vaginitis[Ref]

Hematologic

Frequency not reported: Leukocytosis, petechial rash[Ref]

Hepatic

Rare (less than 0.1%): Disorders of hepatic function (e.g., increased AST)[Ref]

Immunologic

Common (1% to 10%): Pneumonia

Uncommon (0.1% to 1%): Septicemia[Ref]

Metabolic

Common (1% to 10%): Decreased appetite

Frequency not reported: Blood glucose increased[Ref]

Musculoskeletal

Very common (10% or more): Hypotonia (up to 52%), lower extremity weakness (up to 15%), disturbances of gait and balance

Common (1% to 10%): Muscular weakness, myalgia, upper extremity weakness, back pain, muscular hypertonia[Ref]

Nervous system

Very common (10% or more): Somnolence (up to 28%), drowsiness (up to 18%), headache (up to 16%), seizures (especially on discontinuation of therapy) (up to 15%), sedation, dizziness (up to 12%)

Common (1% to 10%): Fatigue, ataxia, tremor, lightheadedness, lassitude, exhaustion, numbness/itching/tingling, slurred speech, lethargy, hypertonia, paresthesia

Rare (less than 0.1%): Dysarthria, dysgeusia, syncope, dyskinesia, coma, potentially life-threatening withdrawal symptoms (as a result of sudden interruption of drug delivery)[Ref]

Other

Common (1% to 10%): Tinnitus, pain, asthenia

Uncommon (0.1% to 1%): Accidental injury, weight loss

Very rare (less than 0.01%): Hypothermia

Frequency not reported: Drug withdrawal syndrome

Uncommon (0.1% to 1%): Subdural hemorrhage, accidental injury, weight loss[Ref]

Ocular

Common (1% to 10%): Nystagmus, visual impairment, accommodation disorder, blurred vision, double vision, amblyopia[Ref]

Psychiatric

Common (1% to 10%): Confusional state, hallucination, depression, insomnia, euphoric mood, nightmare, personality changes

Uncommon (0.1% to 1%): Memory loss/impairment, suicidal ideation, attempted suicide

Rare (less than 0.1%): Excitement[Ref]

Renal

Very rare (less than 0.01%): Kidney calculus[Ref]

Respiratory

Common (1% to 10%): Respiratory depression, hypoventilation, dyspnea, bradypnea, feeling of pressure in the chest[Ref]

Frequently asked questions

References

1. Product Information. Lioresal (baclofen). Medtronic Neurological. 2001.

2. Product Information. Lioresal Intrathecal (baclofen). Medtronic Neurological. 2001.

3. Cerner Multum, Inc. UK Summary of Product Characteristics.

4. Pharmaceutical Society of Australia. APPGuide online. Australian prescription products guide online. http://www.appco.com.au/appguide/default.asp 2006.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.