I've been having three-monthly B12 injections for almost three years now; a few days ago, for the first time, I had an outbreak of hives about an hour after my jab. I wonder if anyone has any suggestions about why this might have happened all of a sudden?
For context: I've never previously been prone to hives, but over the past two years, while I've been quite unwell due to hypothyroidism and chronic fatigue, I've had them develop four times after consuming, respectively, cod in tomato sauce, quorn in curry sauce, antibiotics, and a mince pie. I haven't had hives for several months, until this jab.
Oh, before I forget: the day following my jab, I ate from the same loaf, butter dish, milk carton and jam jar for breakfast without any reaction, so I think it was to do with the jab rather than food.
I'd be very grateful if anyone has any insights or experience with this.