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This page presents data from the FDA Adverse Event Reporting System (FAERS) and the FDA-approved drug label. A report submitted to FAERS does not prove a drug caused the reported event. Always consult a healthcare provider about medications.

Baclofen

gamma-aminobutyric acid-ergic agonist
Last updated: June 18, 2026
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Baclofen is a medication, a gamma-aminobutyric acid-ergic agonist. According to the FDA-approved label, Baclofen tablets, USP are useful for the alleviation of signs and symptoms of spasticity resulting from multiple sclerosis, particularly for the relief of flexor spasms and concomitant pain, clonus, and muscular rigidity. FAERS contains 84,530 submissions naming this drug from 2003 through 2026; the top three reactions cited are fatigue, pain, and drug ineffective.

Most-Reported Reactions

Counts of the reactions most often cited in FAERS submissions that named Baclofen. Inclusion here does not establish causation - submitters describe what was observed, not what was confirmed. One submission can list several reactions, so the totals exceed the report count.

FATIGUE 6,210 (7.3%) PAIN 5,689 (6.7%) DRUG INEFFECTIVE 5,531 (6.5%) FALL 5,456 (6.5%) NAUSEA 4,649 (5.5%) HEADACHE 4,391 (5.2%) GAIT DISTURBANCE 4,130 (4.9%) OFF LABEL USE 3,730 (4.4%) DIZZINESS 3,582 (4.2%) URINARY TRACT INFECTION 3,512 (4.2%) ASTHENIA 3,431 (4.1%) MULTIPLE SCLEROSIS RELAPSE 3,406 (4.0%) MUSCLE SPASMS 3,336 (3.9%) DIARRHOEA 3,086 (3.7%) VOMITING 2,860 (3.4%)

Patient Demographics

Patient sex and age across the FAERS submissions that named Baclofen. Percentages here are computed only from submissions where these fields were filled in - many leave them blank.

By Sex

Female Male Unknown

By Age Group

0-17 18-44 45-64 65+

Severity Outcomes

Severity flags recorded across the 84,530 FAERS submissions that named Baclofen. Each bar shows the count of those reports carrying that flag. A single case can carry more than one (a hospitalization that became life-threatening, for example), so these bars are independent rates - they don't sum to 100%. Inclusion of a case under any flag does not establish that the drug caused the outcome.

DEATH 6,360 (7.5%) HOSPITALIZATION 27,673 (32.7%) LIFE-THREATENING 2,725 (3.2%) DISABLING 2,137 (2.5%)

Submissions Per Quarter

Quarterly count of FAERS submissions that named Baclofen. Ups and downs on this chart can track prescribing volume, news cycles, or shifts in how reports get filed, rather than the drug becoming safer or more dangerous.

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026

From the FDA-Approved Label

Excerpts from the official FDA-approved prescribing information for Baclofen. This is the authoritative source on indications, warnings, and known adverse reactions.

Indications

Baclofen tablets, USP are useful for the alleviation of signs and symptoms of spasticity resulting from multiple sclerosis, particularly for the relief of flexor spasms and concomitant pain, clonus, and muscular rigidity. Patients should have reversible spasticity so that baclofen treatment will aid in restoring residual function. Baclofen tablets, USP may also be of some value in patients with spinal cord injuries and other spinal cord diseases. Baclofen tablets, USP are not indicated in the treatment of skeletal muscle spasm resulting from rheumatic disorders. The efficacy of baclofen in stroke, cerebral palsy, and Parkinson's disease has not been established and, therefore, it is not recommended for these conditions.

Warnings

a. Neonatal Withdrawal Symptoms: Withdrawal symptoms have been reported starting hours to days after delivery in neonates whose mothers were treated with oral baclofen throughout pregnancy. The symptoms of withdrawal in these infants have included increased muscle tone, tremor, jitteriness, and seizure. If the potential benefit justifies the potential risk to the fetus and oral baclofen is continued during pregnancy, gradua ly reduce the dose and discontinue baclofen before delivery. If slow withdrawal is not feasible, advise the parents or caregivers of the potential for neonatal withdrawal. b. Abrupt Drug Withdrawal: Hallucinations and seizures have occurred on abrupt withdrawal of baclofen. Therefore, except for serious adverse reactions, the dose should be reduced slowly when the drug is discontinued. c. Impaired Renal Function: Because baclofen is primarily excreted unchanged through the kidneys, it should be given with caution, and it may be necessary to reduce the dosage. d. Stroke: Baclofen has not significantly benefited patients with stroke. These patients have also shown poor tolerability to the drug. e. (continues in label)

Adverse Reactions (from label)

The most common is transient drowsiness (10 to 63%). In one controlled study of 175 patients, transient drowsiness was observed in 63% of those receiving baclofen compared to 36% of those in the placebo group. Other common adverse reactions are dizziness (5 to 15%), weakness (5 to 15%) and fatigue (2 to 4%). Others reported: Neuropsychiatric: Confusion (1 to 11%), headache (4 to 8%), insomnia (2 to 7%); and, rarely, euphoria, excitement, depression, hallucinations, paresthesia, muscle pain, tinnitus, slurred speech, coordination disorder, tremor, rigidity, dystonia, ataxia, blurred vision, nystagmus, strabismus, miosis, mydriasis, diplopia, dysarthria, epileptic seizure. Cardiovascular: Hypotension (0 to 9%). Rare instances of dyspnea, palpitation, chest pain, syncope. Gastrointestinal: Nausea (4 to 12%), constipation (2 to 6%); and rarely, dry mouth, anorexia, taste disorder, abdominal pain, vomiting, diarrhea, and positive test for occult blood in stool. Genitourinary: Urinary frequency (2 to 6%); and rarely, enuresis, urinary retention, dysuria, impotence, inability to ejaculate, nocturia, hematuria. (continues in label)

FDA label effective date: 2026-01-21

Disclaimer

AdverseEvent.ai is not affiliated with the FDA. Adverse-event counts come from the FDA Adverse Event Reporting System (FAERS). Drug labels come from the FDA drug label dataset. A report submitted to FAERS does not prove a drug caused the reported event — always consult a healthcare provider about medications. This site is for informational purposes only and is not medical advice.