Yes, you can generally take ibuprofen and a muscle relaxer together. This combination is commonly prescribed for conditions like acute back pain and muscle spasms, and clinical trials have found it to be safe and well tolerated in most adults. That said, the combination does come with more side effects than ibuprofen alone, and certain people should avoid it entirely.
Why the Combination Works
Ibuprofen and muscle relaxers target pain through different pathways. Ibuprofen reduces inflammation and pain at the site of injury, while muscle relaxers work in the brain and spinal cord to calm muscle spasms and reduce tightness. Because they act on separate systems, taking both can provide broader relief than either one alone.
Clinical research supports this. Studies on acute low back pain have found that adding a muscle relaxer to an anti-inflammatory like ibuprofen provides better short-term pain relief than the painkiller by itself. One trial specifically tested ibuprofen (400 mg) combined with a muscle relaxer (chlorzoxazone 500 mg) three times daily for seven days and found the combination safe and effective for back pain with muscle spasm. No serious adverse events were reported, and over 96% of patients tolerated the combination well.
It Depends on Which Muscle Relaxer
Not all muscle relaxers pair equally well with ibuprofen. The results vary depending on the specific drug.
Cyclobenzaprine (Flexeril): A randomized, double-blind trial tested cyclobenzaprine plus ibuprofen against ibuprofen alone for acute muscle strains. The combination didn’t actually improve pain relief. Pain scores dropped nearly identically in both groups over 48 hours. What did change was the side effect rate: 42% of patients on the combination reported nervous system side effects like drowsiness and dizziness at 24 hours, compared to just 18% on ibuprofen alone. So for acute strains, adding cyclobenzaprine may not be worth the extra drowsiness.
Tizanidine (Zanaflex): A study of 105 patients with acute low back pain found that tizanidine plus ibuprofen was more effective than ibuprofen alone for moderate to severe pain. An interesting bonus: patients taking tizanidine actually had fewer stomach-related side effects than those on ibuprofen with a placebo. Tizanidine appears to have a protective effect on the stomach lining. The tradeoff was more drowsiness and other nervous system effects.
Chlorzoxazone and methocarbamol (Robaxin): Both have been studied alongside ibuprofen with generally good safety profiles. In fact, a combination product containing methocarbamol (500 mg) and ibuprofen (200 mg) is sold over the counter in some countries for muscle and back pain, with a recommended dose of one to two tablets every four to six hours, up to six tablets in 24 hours.
Side Effects to Expect
The most common side effects from combining these medications fall into two categories: stomach issues from the ibuprofen side and drowsiness from the muscle relaxer side.
Ibuprofen can cause gastritis, stomach pain, bloating, and heartburn. At higher doses or with prolonged use, it carries a risk of ulcers and gastrointestinal bleeding, sometimes without warning symptoms. Muscle relaxers add drowsiness, dizziness, mental fog, weakness, and impaired coordination. When you stack both drugs together, you’re essentially accepting both sets of side effects at once.
The drowsiness is worth taking seriously. It can impair your ability to drive, operate equipment, or stay alert at work. Alcohol makes this significantly worse. If you’re taking both medications, avoid drinking.
Who Should Avoid This Combination
While the combination is generally safe for healthy adults, several groups face higher risks.
- Adults over 65: The American Geriatrics Society’s Beers Criteria, a widely used guide for medication safety in older adults, flags both ibuprofen and skeletal muscle relaxers as potentially inappropriate for this age group. Ibuprofen increases bleeding risk in older patients, while muscle relaxers raise the risk of sedation, falls, and fractures. Taking both together compounds these concerns. If ibuprofen is used in older adults, the recommended over-the-counter limit is 1,200 mg per day for no more than seven days.
- People with kidney disease: Ibuprofen can reduce blood flow to the kidneys. In healthy people this is rarely a problem, but in those with existing kidney disease, it can trigger acute kidney failure.
- People with liver cirrhosis: The liver processes both ibuprofen and most muscle relaxers. Liver cirrhosis, especially with fluid buildup, makes the kidneys heavily dependent on the same chemical signals that ibuprofen blocks. This can lead to sudden kidney problems on top of the liver issues.
- People with heart failure: Ibuprofen can cause fluid retention and worsen heart failure. It should be avoided or used very cautiously in this group.
- People taking blood pressure medications: The combination of ibuprofen with certain blood pressure drugs (particularly ACE inhibitors or diuretics) can stress the kidneys.
Timing and Practical Tips
You’ve probably heard you should take ibuprofen with food to protect your stomach. This advice is extremely common, but the evidence behind it is surprisingly thin. A systematic review in the British Journal of Clinical Pharmacology found no proof that food actually reduces stomach irritation from ibuprofen. What food does do is slow absorption and reduce the peak concentration of the drug in your blood, which can delay and weaken pain relief. If your stomach handles ibuprofen fine on its own, taking it without food will likely get you faster results.
If you do experience stomach discomfort from ibuprofen, eating a small amount beforehand is a reasonable practical choice, even if the formal evidence is lacking. The muscle relaxer can typically be taken at the same time as the ibuprofen without any timing concerns.
For most acute pain situations, this combination is meant to be short-term. Clinical trials have generally studied it over periods of 7 to 14 days. Muscle relaxers lose their effectiveness over longer periods and are not intended for chronic use, and prolonged ibuprofen use increases the risk of stomach bleeding and kidney problems.
When the Combination May Not Help
Adding a muscle relaxer doesn’t always improve things. The cyclobenzaprine research is a good example: for simple muscle strains, ibuprofen alone worked just as well, and the muscle relaxer only added drowsiness. Muscle relaxers tend to be more useful when there’s a clear spasm component to the pain, such as the tight, cramping sensation that can accompany acute back injuries. If your pain is more of a general ache or soreness without spasm, ibuprofen alone may be all you need.