Most common muscle relaxers can be taken with Wellbutrin (bupropion), but all of them carry some level of interaction risk because they affect the central nervous system. The key is understanding which combinations pose minor, manageable concerns versus which ones require extra caution. No muscle relaxer is completely free of interaction potential with Wellbutrin, but several are routinely prescribed alongside it with appropriate monitoring.
Why Wellbutrin Interacts With Muscle Relaxers
Wellbutrin is classified as a central nervous system (CNS) stimulant-type antidepressant, and muscle relaxers work by depressing CNS activity to reduce muscle spasms. When you combine these, the muscle relaxer can amplify certain Wellbutrin side effects like dizziness, poor concentration, drowsiness, unusual dreams, and trouble sleeping. The Mayo Clinic specifically lists muscle relaxants among the drug categories that can worsen these side effects when taken with bupropion.
Wellbutrin also lowers the seizure threshold, meaning it makes seizures slightly more likely than baseline. This is the most clinically significant concern. Any additional CNS-active drug, including muscle relaxers, can compound that risk. The practical effect is that your prescriber needs to weigh the type of muscle relaxer, your dose of Wellbutrin, and your personal seizure risk factors before greenlighting the combination.
Cyclobenzaprine (Flexeril)
Cyclobenzaprine is one of the most commonly prescribed muscle relaxers and, despite theoretical concerns, has a reasonable safety track record alongside Wellbutrin. The main worry is serotonin syndrome, a rare but serious reaction that can happen when two drugs that boost serotonin activity overlap. Cyclobenzaprine is structurally similar to older antidepressants and has mild serotonin effects of its own.
However, a case series published in the Journal of Medical Cases tracked patients taking cyclobenzaprine alongside various psychotropic medications, including bupropion, over roughly 24 to 25 accumulated patient-years. The researchers found no evidence of serotonin syndrome or other significant adverse reactions across that entire observation period. Their conclusion was “cautious optimism” about combining cyclobenzaprine with serotonin-active medications. The one exception they flagged was MAO inhibitors, which are a different class of antidepressant from Wellbutrin.
This doesn’t mean the combination is risk-free, but it does suggest that for most people, cyclobenzaprine alongside Wellbutrin is a workable option when a prescriber is monitoring for symptoms.
Tizanidine (Zanaflex)
Tizanidine carries a moderate interaction rating with bupropion. The interaction here is less about serotonin and more about how your body processes these drugs. Wellbutrin affects certain liver enzymes, and when you quit smoking while on Wellbutrin (a common scenario, since one form of bupropion is prescribed specifically for smoking cessation), your tizanidine levels can shift. Smoking speeds up the breakdown of tizanidine, so when you stop, more tizanidine stays in your system, potentially increasing sedation and blood pressure drops.
If you’re prescribed both, your doctor may need to adjust the tizanidine dose over time, particularly if your smoking status changes. The combination is used in practice but requires closer follow-up than some other options.
Baclofen
Baclofen works differently from most other muscle relaxers. It acts on GABA receptors in the spinal cord rather than working centrally in the brain the way cyclobenzaprine does. This mechanism makes it less likely to interact with Wellbutrin’s serotonin and dopamine activity. The general CNS depression concern still applies: combining baclofen with Wellbutrin can increase drowsiness and dizziness. But baclofen doesn’t carry the same serotonin syndrome risk that cyclobenzaprine does, which makes it a commonly considered option for people on antidepressants.
Methocarbamol (Robaxin)
Methocarbamol is a milder muscle relaxer that works through general CNS depression rather than targeting specific neurotransmitter systems. It doesn’t have significant serotonin activity, so the serotonin syndrome concern is essentially off the table. The remaining issue is the additive sedation that comes with any CNS depressant paired with Wellbutrin. For short-term muscle spasm relief, methocarbamol is often considered one of the lower-risk options alongside bupropion because of its relatively simple mechanism and shorter duration of action.
What Side Effects to Watch For
Regardless of which muscle relaxer you take with Wellbutrin, there are overlapping side effects to be aware of. Increased drowsiness is the most common, especially in the first few days. You may also notice more pronounced dizziness when standing up, difficulty concentrating, or disrupted sleep patterns. These effects tend to be strongest when you first start the muscle relaxer or when doses change.
The more serious concern is seizure risk. Wellbutrin already lowers the seizure threshold in a dose-dependent way, meaning higher doses carry greater risk. Adding a CNS depressant can further alter that threshold. Signs of a seizure include sudden uncontrollable shaking, loss of consciousness, confusion, or staring spells. If you have a history of seizures, head injury, eating disorders, or alcohol withdrawal, the combination requires especially careful consideration.
Serotonin syndrome is the other rare but serious risk, primarily with cyclobenzaprine. Symptoms include agitation, rapid heart rate, elevated body temperature, muscle twitching or rigidity, and in severe cases, loss of coordination. These symptoms typically develop within hours of starting or increasing a dose.
Practical Considerations
If you’re already on Wellbutrin and need a muscle relaxer for an acute injury or chronic spasm, the conversation with your prescriber will typically focus on a few factors: how long you’ll need the muscle relaxer, what dose of Wellbutrin you’re on, and whether you have any additional seizure risk factors. Short-term use of a muscle relaxer (a week or two for a back spasm, for example) carries less cumulative risk than long-term daily use.
Timing can also help. Taking the muscle relaxer at bedtime, when you’d be sleeping through the peak sedation anyway, is a common strategy to minimize daytime drowsiness. Avoiding alcohol entirely while on both medications reduces the CNS depression load significantly.
Non-drug alternatives are also worth considering as complements or substitutes. Heat therapy, physical therapy, gentle stretching, and topical pain relievers don’t interact with Wellbutrin at all and can reduce how much oral muscle relaxer you actually need.