From the Guidelines
Baclofen is contraindicated in patients with a history of hypersensitivity to the drug or its components, and its use should be avoided in patients with certain medical conditions, such as seizure disorders, psychotic disorders, or schizophrenia, due to potential adverse effects. The medication should be used with caution in patients with renal impairment, as it is primarily excreted by the kidneys, and dose adjustments may be necessary 1. Patients with respiratory insufficiency should also avoid baclofen, as it may depress respiratory function.
Key Considerations
- Baclofen may worsen skeletal muscle spasticity due to rheumatic disorders, cerebral palsy, Parkinson's disease, or stroke, although it can be considered for severe spastic hypertonia that does not respond to other interventions 1
- The medication can lower the seizure threshold, making it a concern for patients with seizure disorders 1
- Baclofen can exacerbate psychiatric symptoms in patients with psychotic disorders or schizophrenia, and its use should be carefully considered in these cases
- Pregnant women should use baclofen only if clearly needed, as safety during pregnancy is not established
Mechanism of Action and Withdrawal
Baclofen works by activating GABA-B receptors in the spinal cord, reducing the release of excitatory neurotransmitters and decreasing muscle tone. Abrupt discontinuation can cause serious withdrawal symptoms, including hallucinations, seizures, and high fever, so the medication should always be tapered gradually when stopping treatment 1.
Treatment Guidelines
According to the American Heart Association/American Stroke Association guidelines, oral antispasticity agents like baclofen can be useful for generalized spastic dystonia, but may result in dose-limiting sedation or other side effects 1. Intrathecal baclofen therapy may be considered for severe spastic hypertonia that does not respond to other interventions, and targeted injection of botulinum toxin into localized muscles can be recommended to reduce spasticity and improve range of motion 1.
From the FDA Drug Label
Hypersensitivity to baclofen. The contraindications for Baclofen are:
- Hypersensitivity to baclofen 2
From the Research
Contraindications for Baclofen
The following are contraindications for Baclofen:
- Patients with a history of stroke or cerebral hemorrhage 3
- Patients with severe respiratory depression 3
- Patients with a history of epilepsy or seizure disorders, as Baclofen may potentiate seizures 4
- Patients with advanced nephropathy, as Baclofen toxicity has been reported in patients with renal dysfunction 5
- Patients with hypotension, as Baclofen may cause a decrease in blood pressure 3
- Patients with peptic ulcer disease, as Baclofen may cause gastrointestinal side effects 3
Precautions for Baclofen Use
The following precautions should be taken when using Baclofen:
- Patients should be monitored for signs of toxicity, such as somnolence, confusion, and respiratory depression 5
- Patients should be started on a low dose and gradually titrated upwards to minimize adverse effects 3
- Patients with renal impairment should be closely monitored for signs of toxicity, as Baclofen is primarily excreted by the kidneys 5
- Patients should be advised to avoid driving or operating heavy machinery while taking Baclofen, as it may cause drowsiness and impaired cognitive function 3
Special Considerations
The following special considerations should be taken into account when using Baclofen:
- Baclofen should be used with caution in patients with a history of substance abuse, as it may be habit-forming 3
- Baclofen should be used with caution in patients with a history of psychiatric disorders, as it may cause psychiatric side effects such as hallucinations and anxiety 6
- Baclofen should be used with caution in patients with a history of muscular dyskinesia, as it may cause or exacerbate this condition 6