5 Baclofen Side Effects: Symptoms, Risks and Management

Oral baclofen (Lioresal) has long been a cornerstone in the management of muscle spasticity, offering relief from spinal cord lesions and multiple sclerosis. This FDA-approved medication effectively alleviates reversible spasticity, flexor spasms, clonus, and associated pain, making it a valuable medication in neurological treatment.

Yet, since prescriptions for non-opioid therapies like baclofen are on the rise, patients need to be aware of its potential downsides. Muscle weakness, nausea, drowsiness, and paraesthesia are common adverse effects impacting 10% and 75% of patients. Baclofen abuse and dependence can also happen.

Whether you are a patient or a healthcare provider, continue reading to learn about the most important side effects of baclofen so you can maximize its benefits while minimizing its risks.

Table Of Contents:

• Baclofen Overview
• 5 Baclofen Side Effects in Adults
• Baclofen Side Effects in the Elderly
• Can Baclofen Cause Weight Gain?
• Does Baclofen Cause Weight Loss?
• Baclofen Long Term Side Effects
• What Are The Side Effects Of Baclofen? – Final Thoughts
• People Also Ask

Baclofen Overview

Baclofen is a muscle relaxant and antispastic agent that works as a gamma-aminobutyric acid (GABA) agonist. This action mimics GABA, a neurotransmitter that inhibits nerve transmission in the brain. It results in decreased muscle excitability and reduced spasticity, relieving painful muscle contractions and improving patient mobility and comfort.

Baclofen is FDA-approved for the treatment of reversible spasticity, particularly in conditions like multiple sclerosis and spinal cord lesions. It is often prescribed to manage:

• Flexor Spasms: Sudden, involuntary contractions of the muscles that flex the limbs.
• Clonus: Rapid, rhythmic muscle contractions.
• Concomitant Pain: Pain associated with muscle spasms and spasticity.

In addition to its primary uses, baclofen is sometimes prescribed off-label for other conditions, such as alcohol use disorder, hiccups, and certain neuropathic pain syndromes due to its central nervous system (CNS) depressant effects. These CNS depressant effects may cause collateral issues.

Let’s review five side effects of baclofen:

5 Baclofen Side Effects in Adults

Results suggest that oral baclofen is highly effective for many patients with spasticity, regardless of the underlying disease or severity. However, baclofen adverse effects impact many patients, limiting its usefulness and affecting treatment adherence.

Here, we provide a list of common side effects to help you understand what to expect while taking your baclofen pill:

• Drowsiness/Transient Sedation

The most probable side effect you can feel under baclofen treatment is sleepiness. Two main factors cause this sleepiness: 1) GABA inhibition and 2) anticholinergic effects.

As we mentioned, baclofen mechanism of action reduces nerve transmission in the brain and spinal cord. This inhibition decreases neuronal excitability, alleviating muscle spasticity. However, it also results in a general depressant effect on the central nervous system (CNS), leading to drowsiness.

Additionally, baclofen has anticholinergic effects, which block the action of acetylcholine, a neurotransmitter involved in many functions, including muscle movement and alertness. The combination of CNS depressant and anticholinergic effects contributes to baclofen’s overall sedative impact.

Fortunately, the drowsiness is considered transient sedation because it typically occurs at the start of treatment or when baclofen dosage increases and often diminishes as the body adjusts to the medication over time. To manage this baclofen side effect, consider the following strategies:

• Start with a low dose and gradually increase it as tolerated to allow the body to adjust.
• Take baclofen doses during periods of low activity or before bedtime.
• Avoid consuming alcohol and other CNS depressants, which can exacerbate drowsiness.
• Refrain from high-focus activities such as driving or machinery operation.
• Regularly consult with your doctor to monitor your sedation and adjust the dosage if necessary.

• Headache

Blockage of acetylcholine by cyclobenzaprine also affects the regulation of muscle activity and vasodilation, which can lead to vasoconstriction (narrowing of blood vessels), reducing blood flow to the brain and potentially causing cyclobenzaprine side effects such as headaches.

Headaches shouldn’t be severe, and you may manage them at home with:

• Your doctor’s approval, take over-the-counter medication (Tylenol or Advil).
• Applying a cold or warm compress to the forehead or neck.
• Avoid combining cyclobenzaprine with other CNS depressants without medical advice.
• Regular exercise can help reduce tension and prevent headaches.
• Limit screen time to rest your eyes and reduce visual overstimulation.

• Nausea and Vomiting

Nausea, vomiting, and hiccups are troubling complications associated with sedation and general anesthesia. Baclofen can cause nausea due to its effects on the brain’s chemoreceptor trigger zone (CRTZ), which is not protected by the blood-brain barrier.

As a GABA agonist, baclofen alters neurotransmitter activity, impacting the brain’s vomiting center and leading to feelings of nausea. Additionally, baclofen’s muscle relaxant properties can affect the smooth muscles of the gastrointestinal tract, potentially slowing down gastric motility and causing gastrointestinal discomfort, contributing to nausea.

To manage this side effect of baclofen, you can:

• Take baclofen with small meals or snacks to reduce stomach irritation.
• Drink plenty of water throughout the day to stay hydrated.
• Take natural remedies like ginger tea or peppermint to soothe the stomach and reduce nausea.
• Consult with your doctor about using over-the-counter or prescription anti-nausea medications if necessary.
• Identify and avoid foods or smells that trigger nausea, as individual sensitivities vary.

• Confusion

This baclofen side effect is also caused by the medication’s central nervous system (CNS) depressant effects.

This depression can affect cognitive functions, leading to confusion, especially when the dosage is high or increased too rapidly. Additionally, baclofen’s impact on the balance of neurotransmitters in the brain can disrupt normal cognitive processes, contributing to feelings of disorientation and confusion.

To manage baclofen-induced confusion, consider the following strategies:

• Regularly monitor cognitive function and report any significant changes to a healthcare provider.
• Ensure adequate hydration, as dehydration can exacerbate confusion and other side effects.
• Maintain a balanced diet to support overall brain health and cognitive function.
• Review all medications to identify potential baclofen interactions that could exacerbate confusion.
• Establish a routine and use organizational tools (like calendars and reminders) to manage daily activities.
• Avoid consuming alcohol and other CNS depressants, which can worsen confusion and cognitive impairment.

• Rapid Heart Beat

Baclofen can affect blood pressure due to its impact on the central nervous system (CNS) and the autonomic nervous system.

As a gamma-aminobutyric acid (GABA) agonist, baclofen reduces neuronal excitability, influencing the autonomic regulation of blood pressure. Research on anesthetized rats has shown that low doses of baclofen can produce a transient fall in blood pressure and heart rate, while higher doses result in a marked and prolonged increase in blood pressure and heart rate.

This response is due to baclofen’s effect on the central sympathetic nervous system, which, depending on the dosage, can lead to vasodilation or vasoconstriction.

• Regularly checking your blood pressure with home monitors.
• Follow a balanced diet rich to support overall cardiovascular health.
• Reduce salt intake, avoid high-fat foods, and limit caffeine overconsumption.
• Engage in regular physical activity to help maintain healthy blood pressure levels.
• Avoid consuming alcohol and other CNS depressants that could worsen blood pressure issues.
• Report any severe or persistent symptoms to your healthcare provider.

Baclofen Side Effects in the Elderly

An increasing number of analyses report that drugs with anticholinergic effects are associated with an increased risk of cognitive impairment and all-cause mortality in older people. In the Anticholinergic Burden (ACB), baclofen has been assigned two points, indicating a moderate anticholinergic burden.

This score is a useful tool to raise awareness of the anticholinergic effects of different medicines. Drugs are assigned one, two, or three points based on their anticholinergic potency. The higher the score, the greater the anticholinergic effect.

Anticholinergics should be prescribed with caution, as elderly patients are more likely to experience adverse effects such as:

• Constipation: Reduced gastrointestinal motility.
• Urinary Retention: Impaired bladder function due to anticholinergic effects.
• Dry Mouth/Eyes: Decreased saliva and tear production due to anticholinergic effects.
• Sedation: Increased sleepiness and drowsiness.
• Confusion and Delirium: Altered mental status due to CNS depressant effects.
• Photophobia: Sensitivity to light can be exacerbated by baclofen.
• Falls: Increased risk due to sedation and impaired motor function.
• Reduced Cognition: Cognitive impairment that can be potentially misdiagnosed as dementia.

Can Baclofen Cause Weight Gain?

Drugs that act on the central nervous system can frequently cause changes in appetite and energy expenditure, potentially leading to weight changes.

Information from research studies shows an association between weight gain and the use of baclofen. If you have a condition for which baclofen is prescribed, such as a spinal cord injury or multiple sclerosis, it may be challenging to exercise. Limited physical activity can contribute to baclofen weight gain.

Does Baclofen Cause Weight Loss?

Baclofen has been shown to cause weight loss through several mechanisms potentially. Research indicates that baclofen can reduce fat intake when access to food is limited to brief periods under non-food-deprived conditions. Baclofen can reduce the size of a fat binge as induced by limited access. This appetite suppression may contribute to weight loss.

Another study concluded that weight loss is a possible side effect of baclofen. The researchers noted that baclofen suppresses cravings for pure fat but does not help regulate binge eating of foods high in sugar. This dual effect explains why baclofen can contribute to weight loss in some individuals while allowing for baclofen and weight gain in others.

Baclofen Long Term Side Effects

Baclofen has several potential long-term side effects. Understanding these adverse effects can ensure that patients and healthcare professionals can safely and effectively use baclofen over extended periods.

• Patients may develop a tolerance to baclofen, requiring higher doses to achieve the same therapeutic effect.
• Long-term use of baclofen can lead to physical dependence.
• Abrupt discontinuation may cause baclofen withdrawal symptoms, including hallucinations and seizures.
• Prolonged use may affect cognitive functions, leading to memory issues and confusion.
• Patients might experience mood swings, depression, or emotional instability.
• Chronic use of baclofen can result in persistent muscle weakness
• Long-term baclofen use can slow gastrointestinal motility, leading to chronic constipation.
• Baclofen can potentially lead to chronic blood pressure issues.

What Are The Side Effects Of Baclofen? – Final Thoughts

Adverse events with oral baclofen are common, affecting between 10% and 75% of patients.

These side effects, such as muscle weakness, nausea, confusion and drowsiness, are well-known, reversible, and generally dose-related. Despite these potential side effects, baclofen remains an effective treatment for spasticity, with its benefits often outweighing the drawbacks when used correctly.

If you or a loved one is considering baclofen to manage spasticity or any other condition, consult a healthcare provider to understand the potential benefits and risks.

People Also Ask

Can baclofen cause weight loss?

Yes, baclofen can cause weight loss by reducing appetite and fat intake. Studies show it can suppress cravings for fatty foods, though this effect is less common.

Does baclofen cause water retention?

Baclofen is not typically associated with water retention. The most common side effects involve the central nervous system and gastrointestinal tract.

Can baclofen cause heart problems?

High doses of baclofen can lead to heart issues like increased heart rate and blood pressure due to its effects on the central sympathetic nervous system.

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