I've never gotten a tattoo. It's very likely that the I would have an allergic reaction to the ink. Yes, antihistamines help with pain.

Benadryl does not help me w the pain, but it does w itching, swelling like hiving. When my allergies are really bad, i can take up to 6 a day w atarax. Atarax helps w the giving and itching as well. Keeps me up most time because it has the opposite affect on me. Till allergy season is over and i get it out of my system. Dr's told me it can do that when i have so much in my system. I have a decent size tattoo on my back, but it's never bothered me like that. I do know i cannot get anymore because of fibromyalgia.

I take Benadryl every night with magnesium helps sleeping and spasms,pain

I used to get it a lot with the red ink in my dragon tattoo and then it stopped. I have a black peony on my knee and it randomly gets raised in spots. It’s happened with one other one as well, and seems to be randomly. But some other tattoos have never had it happen.