Baclofen: Side Effects, Uses & Monitoring
Baclofen injection (intrathecal) is indicated for use in the management of severe spasticity.
- Data source
- FDA labeling via NIH DailyMed (label 11ba5575…)
- Label version
- current
- Last reviewed
- 2026
Reported adverse reactions
Reactions listed in current FDA labeling, with the highest frequency reported across summarized placebo-controlled trials.
| Adverse reaction (as reported in labeling) | Reported frequency* |
|---|---|
| Vomiting | 6.2% |
| Somnolence | 5.7% |
| Hypotonia | 5.4% |
| Paresthesia | 2.4% |
| Dizziness | 1.7% |
| Nausea and vomiting | 1.6% |
| Headache | 1.6% |
| Nausea | 1.4% |
| Hypotension | 1% |
| Back pain | 0.9% |
| Urinary retention | 0.7% |
| Asthenia | 0.7% |
| Convulsion | 0.5% |
| Confusion | 0.5% |
| Ambylopia | 0.5% |
| Fever | 0.5% |
| Thinking abnormal | 0.5% |
| Agitation | 0.5% |
| Chills | 0.5% |
| Tremor | 0.5% |
*Highest percentage reported for the active moiety across placebo-controlled trial tables in current FDA labeling. Values reflect trial reporting, not your individual risk.
Labeled uses (from FDA prescribing information)
Baclofen injection (intrathecal) is indicated for use in the management of severe spasticity. Patients should first respond to a screening dose of intrathecal baclofen prior to consideration for long term infusion via an implantable pump. For spasticity of spinal cord origin, chronic infusion of baclofen injection (intrathecal) via an implantable pump should be reserved for patients unresponsive to oral baclofen therapy, or those who experience intolerable CNS side effects at effective doses. Patients with spasticity due to traumatic brain injury should wait at least one year after the injury before consideration of long term intrathecal baclofen therapy. Baclofen injection (intrathecal) is intended for use by the intrathecal route in single bolus test doses (via spinal catheter or lumbar puncture) and, for chronic use, only in implantable pumps approved by the FDA specifically for the administration of baclofen injection (intrathecal) into the intrathecal space. Spasticity of Spinal Cord Origin: Evidence supporting the efficacy of baclofen injection (intrathecal) was obtained in randomized, controlled investigations that compared the effects of either a single intrathecal dose or …
Conditions associated with Baclofen in labeling
Frequently Asked Questions
What is Baclofen used for?
FDA labeling lists the approved uses shown above under "Labeled uses." This summary is informational; only a qualified prescriber can determine whether a medication is appropriate for you.
What are the most commonly reported side effects of Baclofen?
The table above shows adverse reactions and the highest frequencies reported in placebo-controlled trials summarized in current FDA labeling for Baclofen. Individual risk varies.
Does Baclofen require lab monitoring?
Monitoring needs vary. Ask your healthcare provider whether any lab tests apply while taking Baclofen.
Where does this information come from?
All clinical facts on this page were extracted from the current FDA-registered product labeling for this ingredient, published by manufacturers through NIH DailyMed. See the source link below.
Medical disclaimer: Educational content extracted from public FDA labeling. Not medical advice. Always consult a qualified healthcare professional before starting, stopping, or changing any medication.