Itchiness as a side effect of the COVID vaccine?

My mother received the Pfizer vaccine for both the initial two shot as well as the booster, which she received several months ago. Since then, she’s had terrible itchiness all over. She saw her primary care physician this week, who told her that this was a known side effect. Anyone else seen this? Any idea how to resolve this? She scratches so much as to cause bleeding. And the doctor advised her not to get the second booster.

I’ve heard of having mild allergic reactions (i.e. not anaphylactic shock or something damaging on its own), but not something that would continue that long.

Googling it, there seems to be some suggestion that the shot might allow dormant herpes to reappear, causing itching due to interaction with the nerves. Perhaps that has something to do with it?

Honestly it seems like something to ask the doctor. If they know it’s a side effect, and it hasn’t gone away by now, they really should be considering treatment of some kind. If it’s nerve based, they might give a nerve medication. If it’s allergy based, there’s always creams and allergy medicine.

My mother was prescribed something this week but didn’t like the drowsiness it caused. And she has many allergies so prescribing stuff is always an issue.