Is this sudden red blothchy rash all over an allergic reaction-to what?

[preciousgirl]

I was wondering if anyone could give me ideas on what my rash is coming from. I got 4 trigger point injections with Marcaine done 3 weeks ago for the first time ever for Fibromyalgia. That was on a Friday. The next day-Saturday (about 27hrs later), I discovered that I had several red blotchy rashes all over most of my upper body(chest, breasts, stomach, whole back, shoulders and upper arms, and face. It lasted a few minutes and then disappeared just on its own. It has continued to come back like that everyday and again leave in a few minutes-sometimes up to an hr or so but then keeps coming back more than once a day everyday for the past 3 weeks.The only other thing that I have done differently besides getting those trigger point injections, is that I did increase my Vicoden pills from 1 a day up to 3 a day that Saturday that I got the rash later that evening.That is also the day after the day I got the trigger point injections). It has now been 3 weeks with this red blotchy rash that comes and goes sporadically throughout the day everyday and I don't know what it's from. I tried decreasing the Vicoden back down to 1 pill a day and taking Claritin in day and Benadryl at night and its still not going away and keeps coming back everyday.

So my question is what do you think this rash is and what is it being caused from? Do you think it's an allergic reaction from the trigger point injections or from the Vicoden or neither? My doctor doesn't know what the rash could be from and said he didn't think it was from the Vicoden because I had already been taking 1Vicoden pill a day for 2 months with no rashes up until the day I increased it to 3 pills a day which he says shouldn't make a difference bc if I was allergic, that should've happened even when I was just on 1Vicoden a day. Does anyone know what this sudden red blotchy rash could be from?I would love to know if anyone has any ideas or suggestions.