@lynmen My doc prescribed duloxetine 60mg for back pain several years ago. I have chronic sciatica from spinal stenosis (narrowing of the spinal canal) and foraminal stenosis (narrowing of the openings at the sides of the vertebrae where nerve root bundles exit from the spine). The narrowing puts pressure on the nerve roots exiting in the lumbar region. I'm a golfer, and the sciatica really made it difficult to swing the club. I take a generic duloxetine (a Canadian generic manufacturer). The original drug (Cymbalta, from Lilly), worked wonders for me. Lilly stopped making Cymbalta about two years ago (reason: a 'business decision' - they wanted the platform for making another drug, and I'm guessing it was for the GLP-1 drug, Mounjaro). This decision upset many Cymbalta users like me because the generics did not work for some (quite a few) of us. So, I've tried a bunch of generics here in Canada, and none seem to be as effective as the original Cymbalta. In addition, the generics present a variety of challenges in terms of side effects, not from the 'duloxetine' (this was invented by Lily, and is a well known and standard formulation). So the generic side effects must be due to the non-medicinal additives, or to the way the timed-released mini--balls within the capsules are released inside the colon over the 24+hour period of release. Generic makers do things as cheaply as possible in order to save or make more money. So I would not be surprised that the drug-release mechanisms are different from the way Lilly made theirs. My experience is that, for example, the current generic I'm on uses a less subtle way to release the mini ball's bit of medication. With Cymbalta I never noticed a surge of drug release, ever. The generic I use has a release mechanism that I can often feel in my body as a SURGE of mild but noticeable nausea that lasts about 10 minutes then goes away a few times during the day and night. So my conclusion is that it's a crude release mechanism (dissolving of the wrapper around the little duloxetine balls). I was on Cymbalta for almost 10 years, and never once had a single problem or noticed anything like a 'surge' of medicine.
Anyway, yes Cymbalta was a miracle drug for my sciatica, but the generic duloxetine may not act as well as you hope. Try different generics if you don't like what was prescribed, I expect your pharmacist may have an idea about which supplier's timed duloxetine works best. Definitely worth a try. However, I wouldn't stay on a generic for more than two weeks or even less if you notice it's not helping. You don't want to get addicted to this drug unless it's really helping. It's difficult to wean yourself from it after a few months of use. The other thing I would add - the duloxetine is also an anti-depressant. You might notice, when coming off the drug, your demeanor has changed somewhat, that you're not as relaxed as you were while on the medication. It has happened to me. At my age (82) I'm probably going to be on this for life, which is ok by me. I just wish it was the original Cymbalta. Hope it works for you if you do try it. All the best.