Some people may also experience pruritus, or severe itching, as a symptom of fibromyalgia. 
Itching may occur in fibromyalgia due to certain nerve fibers being activated and causing an itching sensation. Itching and pain share a common pathway positioned in the spinal cord. ... Initially, scratching relieves the itch, but with constant scratching the skin becomes damaged. 
Just as there is no one cause for fibromyalgia, there isn’t a cause for the unexplained itching. Itching is one possible way your nerves can react to the condition.

It’s also possible that itching could be a side effect of medication you are taking for fibromyalgia, such as pregabalin (Lyrica), duloxetine (Cymbalta), or milnacipran (Savella). Always let your doctor know about any side effects that you experience, even if they are not listed as known side effects. Your doctor may need to adjust your dosage or change your medication.

I take Quercetin daily for my itching and allergy relief.
https://draxe.com/nutrition/quercetin/.
Instead of scratching I massage the area and use ice to calm the area.
Here’s a massage tool I use for my back needs. (Theracane)

Yes I've had that itching problem in the beginning of my fibro. Doctors weren't helpful tried all kinds of creams and Benadryl allergy meds, along with icing. Something to do with the nervous system I had read. Allodynia. I had no sign of any rashes just scratching myself raw. It finally just slowed down and went away and of course other fibro problems started. And now I see my oldest daughter going through the same thing itching, she's taking muscle relaxers But that just makes her sleepy so she's not scratching as much. 😕

I know the feeling, I just got over that and I had it for months, my doctor said it was allergies. The medication he prescribed me made it so worse. I stop it. I bought this cream while in the pharmacy waiting for my meds, because it had even started down there, but I couldn’t put the cream there😭 I ended up buying the children Benadryl and taking it at night and the children chewable tables for the day time. It’s helped me my so much that I keep me some just in case it starts back, which it has my 👼🏻 It’s finally went away! What a relief, Sounds like this may be part of the fybro! Oh well, what else is new😩 I’ll be Praying for you to feel better ❤️‍🩹 I took a picture of the items I used, so now when the itching comes back I have it there 🥺😩🤧take care my Angel💞try not to scratch it will made it worse😩

Thanks everyone for the input!
AnnaMarie I have tried Benadryl in the past and it made me too groggy, but did seem to help. Didn't think of the children's dosage. I may try it. Thank you!
I don't think I'm allergic to any of my meds as I have been taking the same ones for years. But I suppose I could have developed one. My doctors have had zero suggestions for how to deal with the itching.
Hjberry thanks for the info on pruritus, new to me.
Unfortunately the consensus seems to be to kind of wing it with whatever over the counter remedy works for you. Sorry so many of you also have this!
Wishing everyone a low pain non-itchy day😊