Do over-the-counter muscle relaxers work?

OTC muscle relaxers | Benefits | Side effects | OTC vs. Rx

Have you ever fallen asleep in an awkward position and woken up with a stiff neck? It hurts or is almost impossible to turn to one side or another. Or maybe you’ve done a hard day of physical work and woke up the next morning with spasms in your lower back? Spasms are those painful, involuntary twitches in your muscles that typically result from an injury or overexertion. 

Minor irritations resulting in spasms or stiffness often resolve on their own over time, but more serious injuries may not. Often, you may need a muscle relaxant to stop the spasming and allow your muscles to loosen up and improve your range of motion. In fact, many times, your healthcare provider may recommend a combination of medications, physical therapy, or lifestyle modifications to treat pain, inflammation, and spasming. Muscle relaxers are almost exclusively prescription only in the United States, but if you wake up one morning with muscle pain, there may be some over-the-counter (OTC) options to help you.

Can you get muscle relaxers over the counter?

There are no medications with a Food and Drug Administration (FDA) approved indication for muscle relaxation available over the counter in the United States. However, you may find some relief from muscle spasms and pain with some OTC agents.

Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or pain relievers like acetaminophen can work to decrease the inflammation and pain associated with muscle injuries. This can provide some immediate relief for many ailments, but if the relief is not adequate, you may still need medical attention. Sometimes, there can be a more serious underlying condition, such as a spinal cord injury.

There is one OTC drug product that is sometimes used off-label (without FDA approval) as a muscle relaxant, and that is guaifenesin. This is the active ingredient in expectorant products such as the brand-name Mucinex. Guaifenesin is indicated as an expectorant that helps to thin and clear phlegm and mucus in the respiratory system. It is often recommended as a part of the treatment for sinus infections, bronchitis, and pneumonia. Although it has never been approved as a muscle relaxer, anecdotal data suggests it helped with spasms and pain in the upper neck and back. One placebo-controlled clinical study compared typical daily doses of either 600 mg or 1200 mg of guaifenesin twice daily to placebo in patients experiencing acute pain and muscle spasms in their back, neck, or shoulders. The 1200 mg dose twice daily showed a 25% reduction in spasm and pain over placebo, and 16% more than the 600 mg dose. The results suggest there may be some clinically relevant use for guaifenesin as a muscle relaxer. This relief is only symptomatic and would not be addressing any more serious underlying issues.

If your healthcare provider determines you need a muscle relaxer, they will likely prescribe a prescription-only muscle relaxer. There are different types of prescription muscle relaxers, which aren’t a universal answer to all muscle ailments. Muscle relaxers generally work on one of two types of muscle conditions: spasticity or spasms. Spasticity refers to how stiff or rigid the muscles are and is typically a long-term or permanent condition of the muscle due to disorders such as cerebral palsy or multiple sclerosis. Spasms are a more temporary condition related to an acute injury or event.

There are three FDA-approved muscle relaxers approved to treat muscle spasticity. These are Lioresal (baclofen), Dantrium (dantrolene), and Zanaflex (tizanidine). Generally speaking, muscle relaxers either work through the central nervous system to block signals or work on the muscle fibers themselves. Baclofen and tizanidine block neuronal pathway signals in the brain and spinal cord. Dantrolene acts directly on the muscle. It is important to note that botulinum toxin, sometimes just called “Botox,” is FDA-approved to treat spasticity on a select few areas of extremities but is not recommended for general use as a muscle relaxant.

A larger group of muscle relaxant agents is approved for muscle spasm treatment. We don’t know the exact mechanisms of action for all muscle relaxers, and they can vary greatly in chemical structure. The data regarding the effectiveness of muscle relaxers is older, and coming to a definitive conclusion on their usefulness is challenging. Prescribers will oftentimes try other treatment options first or combine the muscle relaxer with other agents. Prescription muscle relaxers do have a significant amount of adverse events associated with them primarily due to their central nervous system action. The most common side effects are drowsiness, dizziness, muscle weakness, and headache. Rarely there are more serious side effects like seizures, anaphylactic shock, and allergic reactions. Seek immediate medical help if you show signs of an allergic reaction, such as swelling of the face, lips, or tongue. While muscle relaxers are most commonly available as oral tablets, some, like diazepam, are available as an injection as well.

The muscle relaxers for spasms include:

• Soma (carisoprodol)
• Lorzone (chlorzoxazone)
• Flexeril (cyclobenzaprine)
• Skelaxin (metaxalone)
• Robaxin (methocarbamol)
• Norflex (orphenadrine)
• Valium (diazepam)

**Some items on this list are available under multiple brand names

Read more about muscle relaxants here: List of muscle relaxants: Uses, common brands, and safety information (singlecare.com)

One last agent to mention is medicinal cannabis. There is supporting evidence that cannabis extract use has had a significantly positive effect on muscle cramps and spasms in patients with multiple sclerosis. These patients overall were able to take fewer prescription medications, including pain medications and muscle relaxers. Medicinal cannabis has limited availability, and if you feel it is right for you, you should speak to your prescriber.

What are the benefits of OTC muscle relaxers?

While there are no approved OTC muscle relaxers, you may find sufficient pain relief by taking drugs such as NSAIDs or guaifenesin. This will likely only be the case for mild, short-term irritations to the muscle. Drugs like NSAIDs and guaifenesin are easy to access without a prescription and have minimal side effects when taken as directed. Unlike prescription muscle relaxers, these medications do not have actions on the central nervous system and avoid side effects such as drowsiness and dizziness. When taking NSAIDs, even for just a short period, be sure to eat each time you take a dose to help protect your stomach from irritation.

Side effects and risks of OTC muscle relaxers 

Guiafenesin’s side effects are limited but can include:

• Prolonged cough
• Nausea and vomiting
• Diarrhea
• Stomach pain

Do not take more than the recommended dose. The maximum OTC recommended dose is 1200 mg twice daily. While guaifenesin can be taken for prolonged periods of time, its use as a muscle relaxer is not approved and should not be a long-term treatment choice. If you don’t experience relief within a day or two of taking guaifenesin, you should be speaking to your healthcare provider to make sure there isn’t a more serious issue going on.

Prescription muscle relaxers have more significant side effects and risks. They cause significant drowsiness and dizziness due to their actions in the brain and on the muscles. For this reason, some prescribers will suggest you only take these at night before bedtime. You should not drive or operate heavy machinery when you take them. If you have a history of seizure disorders, you should not take these drugs.

Some conditions may require the long-term use of muscle relaxants, such as cerebral palsy or multiple sclerosis. Most other acute injuries should only need a short-term course of muscle relaxers. 

OTC vs. RX muscle relaxers 

While there are no approved OTC muscle relaxers, drugs like ibuprofen, acetaminophen, or guaifenesin may be able to provide relief from mild muscle ailments. These drugs have minimal and mild side effects and are safe to use in the short term. However, if your spasms and pain are more serious and long-lasting, you should speak to your prescriber to see if prescription drugs would be a better option. Use caution with these treatments because they can cause significant drowsiness and impair your driving ability. 

Your medical provider can help you make the best choice for you. Be sure to let them know of all medications you are already taking and of any medical conditions you have been diagnosed with. If you do need a muscle relaxer, be sure to visit SingleCare’s website for the best pricing available.