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Anything I should know about before trying Flexeril longterm?


Senior Member
I have huge issues with increased muscle tone and spasms and I loved how I felt on Baclofen but it sadly flared my immune mediated SFN. I have yet to see anecdotes of Flexeril flaring neuropathy and Im crossing my fingers that it can increase a bit of muscle function like baclofen did.

I hope its enough with 5mg twice a day. Though some take up to 10mg 3x a day etc. Is there anything I should be aware of? I have pretty good benefit from valium but Im terrified of benzos, so I dont want to take that long term.

"Understanding Flexeril (Cyclobenzaprine)​

Flexeril is the brand name for Cyclobenzaprine, a prescription muscle relaxer that is similar to a class of Antidepressant drugs called Tricyclic Antidepressants."

Can I mess up my brain by taking Flexeril like with benzos?


Senior Member
New York, NY
I didn’t know that Baclofen can cause SFN to worsen or flare. Is that a common side effect?

In any case, I have been on Baclofen, Methocarbamol and Flexeril at various times. Flexeril is the most effective for muscle stiffness and pain in my experience, whereas baclofen doesn’t seem to do much for me except lift my mood slightly.

The only issue with Flexeril is that it is the most sedating of those three meds. Even a 5mg dose makes me drowsy. You might try it first at night for that reason.

It’s chemically closer to tricyclic antidepressants like doxepin than to benzodiazepines. Doxepin seems to be associated with dementia and is usually not prescribed to elderly patients for that reason, but I don’t know if the same applies to Flexeril.


Senior Member
I have not tried baclofen, but I have noticed that phenibut (which I have not taken as a consistent regimen, but as a handful of one-off doses) did seem to worsen my immune-mediated SFN, especially the day after. So perhaps there is something about GABA-B agonism that interacts with SFN in some way?

In any case, as the poster above pointed out, cyclobenzaprine (Flexeril) has a quite different set of mechanisms, which overlap to a degree with the tricyclics -- 5-HT receptor antagonism, alpha-adrenergic antagonism, antihistamine and antimuscarinic. The latter two in particular contribute heavily to sedation, but presumably you get somewhat acclimated to that effect over time.

As for whether it might worsen your SFN, it's hard to say. I wouldn't think any of those effects would cause a problem, necessarily. I've actually ready that M1 muscarinic antagonism enhances nerve growth, though I'm not sure if that would actually happen with this particular drug.