No single muscle relaxer has been proven superior to another for back pain. Systematic reviews comparing the major options found no pattern suggesting one works better than the rest, and many of the trials behind these drugs were low quality with inconsistent methods. That said, muscle relaxers as a class do provide meaningful short-term relief for acute back pain, and the American College of Physicians recommends them alongside anti-inflammatory drugs like ibuprofen and naproxen as a first-line option when medication is needed.
So the real question isn’t which one works best. It’s which one fits your situation, given the differences in side effects, safety risks, and sedation levels.
How Muscle Relaxers Work for Back Pain
Most muscle relaxers prescribed for back pain belong to a category called antispasmodics. These include cyclobenzaprine, methocarbamol, metaxalone, and carisoprodol. They don’t act directly on your muscles. Instead, they work in your brain and spinal cord, dialing down the nerve signals that cause muscles to tighten and spasm. Cyclobenzaprine, the most commonly prescribed, reduces muscle tension by acting on the brainstem. Carisoprodol blocks nerve activity in the spinal cord and a brain region that controls automatic motor responses.
A separate category, antispasticity medications, includes baclofen and tizanidine. These were originally designed for conditions like multiple sclerosis and spinal cord injuries, where muscles become rigid due to damaged nerve pathways. They sometimes get prescribed off-label for back pain, but they target different problems and carry different risks.
The Most Commonly Prescribed Options
Cyclobenzaprine is the workhorse of back pain prescriptions. It has the most clinical data behind it and is the most widely studied for acute low back pain specifically. It’s effective at reducing spasm and improving sleep, which matters because back pain often disrupts rest. The tradeoff is significant drowsiness. Many people feel groggy, foggy, or dizzy, especially in the first few days.
Methocarbamol is another popular choice and is available over the counter in some countries. It tends to cause less sedation than cyclobenzaprine, though the evidence supporting its effectiveness is more limited. Metaxalone has the reputation of being the least sedating muscle relaxer available, with lower rates of dizziness and drowsiness than other options in its class. For people who need to stay functional during the day, these two are often preferred, even if the proof of their effectiveness isn’t as robust.
Tizanidine works well for spasm relief but commonly causes dry mouth and can affect the liver. The FDA recommends liver enzyme testing at baseline and one month after reaching the maximum dose. Baclofen is effective for spasticity-related tightness but tends to cause muscle weakness as a side effect, which can be counterproductive when you’re trying to stay active through a back pain episode.
Carisoprodol deserves special mention because of its risks. Your body converts it into meprobamate, a sedative with known potential for dependence. The DEA classified carisoprodol as a Schedule IV controlled substance in 2011 after finding that its risks, including respiratory depression, cognitive impairment, and addiction, mirror those of other controlled central nervous system depressants. Most prescribers now avoid it when safer alternatives exist.
Adding a Muscle Relaxer to an Anti-Inflammatory
Many people assume that combining a muscle relaxer with an NSAID like naproxen will produce better results than either drug alone. A study of 320 emergency room patients with severe low back pain tested exactly this. All participants took naproxen for 10 days, and one group added cyclobenzaprine while another added an opioid pain reliever. A third group added a placebo. The result: no difference between the three groups in pain relief or functional improvement. Adding cyclobenzaprine on top of naproxen didn’t help more than naproxen by itself.
This doesn’t mean muscle relaxers are useless. It suggests that for many people, a good anti-inflammatory may be doing most of the heavy lifting, and a muscle relaxer’s main added value may be helping with sleep or providing relief when NSAIDs alone aren’t enough or can’t be tolerated.
Side Effects All Muscle Relaxers Share
Every muscle relaxer on the market causes some degree of central nervous system depression. In clinical trials of acute low back pain, patients taking muscle relaxers were about twice as likely to experience dizziness and drowsiness compared to those on placebo. Overall adverse effects were 50% more common. These aren’t occasional side effects; they’re the norm for this drug class.
The sedation can be dangerous when combined with alcohol. Both substances slow brain activity, heart rate, and breathing. Mixing them intensifies those effects and can lead to severely reduced motor coordination, slowed breathing, memory problems, and increased risk of overdose. Opioid pain relievers compound these same risks. If you’re taking a muscle relaxer, treating it like a medication that impairs you the way alcohol does is the safest approach.
Risks for Adults Over 65
Muscle relaxers land on the Beers Criteria, a widely used list of medications considered potentially inappropriate for older adults. The core concerns are sedation, confusion, drops in blood pressure when standing, and a higher risk of falls and fractures. A large retrospective study of Kaiser Permanente patients aged 65 to 99 found that baclofen carried a 69% greater risk of injury outcomes compared to cyclobenzaprine, and tizanidine carried a 34% greater risk. Among the options studied, cyclobenzaprine appeared to be the relatively safer choice in this age group, though all muscle relaxers pose elevated risks for older adults.
How Long You Should Take Them
Muscle relaxers are meant for short-term use. Most prescriptions cover one to two weeks, aligned with the typical timeline of an acute back pain flare. Providers keep courses brief partly because of habituation risk with certain drugs, and partly because the sedating side effects become harder to justify once the acute spasm phase passes. There’s little evidence supporting long-term muscle relaxer use for chronic back pain, and the American College of Physicians guidelines specifically frame them as a tool for acute and subacute episodes.
If your back pain persists beyond a few weeks, the treatment conversation typically shifts toward physical therapy, exercise, and other approaches that address the underlying cause rather than masking the spasm with medication.
Choosing Based on Your Priorities
- If sedation is your biggest concern: Metaxalone and methocarbamol are the least sedating options, though the evidence behind their effectiveness is thinner than for cyclobenzaprine.
- If you want the most studied option: Cyclobenzaprine has the deepest evidence base for acute low back pain. Expect drowsiness, especially early on.
- If you’re over 65: All muscle relaxers carry elevated risks. If one is necessary, cyclobenzaprine appears to have a lower injury risk than baclofen or tizanidine in this population.
- If you’re already taking an NSAID that’s helping: Adding a muscle relaxer may not improve your pain or function meaningfully. The benefit may be limited to nights when spasm disrupts sleep.
- If a provider suggests carisoprodol: Be aware of its controlled substance status and dependence potential. Safer alternatives exist for most people.
The “best” muscle relaxer for back pain is less about which drug is pharmacologically superior and more about which one matches your tolerance for side effects, your daily demands, and how your body responds. Since no head-to-head trial has crowned a winner, the decision is practical, not scientific.