Key takeaways:
Baclofen interacts with many different medications, including alcohol, opioids, and benzodiazepines.
Baclofen interactions can lead to excessive sleepiness, dizziness, and confusion. In severe situations, it can cause trouble breathing and low blood pressure.
Always talk to your healthcare provider or pharmacist before starting a new medication. They can review your current medication list for potential interactions.
Baclofen is a muscle relaxant. It’s FDA approved to treat muscle spasms caused by multiple sclerosis. It's also approved to treat spinal cord injuries. It’s available as a tablet and oral liquid (Fleqsuvy, Ozobax). It's also available as an intrathecal injection (Gablofen, Lioresal intrathecal). “Intrathecal” means it’s injected into the fluid surrounding the spinal cord.
Like most medications, baclofen has drug interactions to be aware of. Interactions can occur with other medications and substances that have similar effects on the body. This includes sleepiness, dizziness, and weakness. In rare instances, this can lead to severe side effects like difficulty breathing.
Below we’ll discuss a few medications and substances that can interact with baclofen. But this isn’t a complete list. Talk to your healthcare provider and pharmacist before starting baclofen. Provide them with an updated list of all your medications. They can help you check for possible baclofen interactions.
1. Alcohol
Muscle relaxers, like baclofen, may interact with alcohol. Drinking alcohol while taking baclofen can cause weakness, dizziness, and confusion.
Baclofen and alcohol impact the central nervous system (CNS). The CNS consists of your brain and spinal cord. Medications and substances that lower the activity of the CNS can cause symptoms:
Lowered concentration
Confusion
Headache
Dizziness
Slowed speech
Problems with coordination
Worsening memory
Slowed breathing
When alcohol and baclofen are combined, these side effects are more likely. If you drink alcohol, talk with your healthcare provider before starting baclofen. They can provide guidance on how much alcohol, if any, is safe to drink with your medication.
2. Opioids
Opioids are a class of medications that are usually used to treat moderate to severe pain. Examples of opioids include oxycodone (Oxycontin, Roxicodone), morphine (MS Contin, Kadian), and tramadol (Ultram).
Individually, opioids and baclofen can both cause your brain to slow down. In 2016, the FDA warned about the risk of combining opioids with other medications that affect the brain. This includes baclofen. They warned that a combination of these medications can cause serious side effects. Slowed and ineffective breathing is possible, and can lead to death in severe cases.
If you take opioids, it’s a good idea to have Narcan (naloxone) on hand at all times. This is especially important if you're taking opioids with a medication that amplifies opioid effects. You can get Narcan without a prescription at your local pharmacy in every state. And in some states, you can get Narcan for free.
Before starting baclofen, make sure to tell your healthcare provider if you’re taking opioids. They may recommend you slowly lower your opioid dose if baclofen is needed. Or they may recommend another medication besides baclofen. It's important to note that the prescribing information for intrathecal baclofen has a specific warning about epidural morphine. Epidural morphine is administered into the spine. Combining these two products can cause difficulty breathing and low blood pressure.
3. Benzodiazepines
Benzodiazepines (BZDs) are a group of medications that treat many health conditions, including anxiety, panic disorder, and more. A few examples of medications in this class include alprazolam (Xanax), clonazepam (Klonopin), and lorazepam (Ativan).
Like opioids, BZDs can slow down your brain, and cause similar side effects as those caused by baclofen. This can lead to more serious symptoms such as slow and shallow breathing, and even death.
If you take BZDs, talk with your healthcare provider before starting baclofen. They may recommend stopping your BZD or adjusting the dose. Or they may recommend avoiding baclofen. But, don’t make any changes to your medications without talking to your healthcare provider. Stopping medications like BZDs abruptly can be dangerous.
4. Sleep medications
Sleep medications — like zolpidem (Ambien) and doxylamine (Unisom Sleep Tabs) — can cause excessive sleepiness when taken with baclofen. Medications that aren’t approved for sleep (but cause sleepiness as a side effect) can also interact with baclofen. This includes trazodone, diphenhydramine (Benadryl), and gabapentin (Neurontin).
Excessive sleepiness can lead to trouble with coordination. It can also impact your ability to complete daily tasks. If you take sleep medication, let your healthcare provider know before starting baclofen. They may recommend you avoid one of these medications entirely.
If you need baclofen and a sleep medication, avoid activities that require you to be alert until you know how the combination affects you. That includes driving and operating heavy machinery.
5. Barbiturates
Barbiturates are a group of medications that treat seizures and sleep problems. Examples include phenobarbital and pentobarbital. Pentobarbital is only used in hospitals because it’s given through a vein.
Barbiturates slow down brain activity and can cause drowsiness on their own (which is what they’re often used for). When combined with baclofen, the risk for severe drowsiness is higher.
If you need a barbiturate, your healthcare provider may recommend stopping baclofen slowly. Or, they may ask you to monitor closely for side effects. These include extreme sleepiness, confusion, or trouble breathing.
6. Other muscle relaxers
There are multiple other muscle relaxers available besides Baclofen. Examples include methocarbamol, cyclobenzaprine (Fexmid, Amrix), and tizanidine (Zanaflex). While these medications don’t all necessarily work just like baclofen, they have a similar effect of muscle relaxation. They can also cause dizziness and drowsiness. When combined with baclofen, these effects can be amplified.
In general, it’s best to avoid taking multiple muscle relaxers at once. If you’re taking baclofen and not feeling relief, talk to your healthcare provider. They may recommend an alternative option.
The bottom line
Baclofen can interact with other medications and substances that slow down brain activity. This includes alcohol, benzodiazepines, and opioids. Baclofen can also interact with sleep medications and barbiturates. These interactions can cause excessive sleepiness, dizziness, or confusion. More seriously, it can drop your blood pressure too low and cause trouble breathing.
Before starting baclofen, talk with your healthcare provider and pharmacist. They can help you check for possible baclofen interactions. But even if an interaction is possible, these medications may still be necessary. Your provider can help you weigh the risks and benefits.
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References
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United States Drug Enforcement Administration. (n.d.). Barbiturates.
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