I get a rash on my arm every time I

Patient: I get a rash on my arm every time I donate blood, draw blood, get vaccinated, or get a mantoux test. At first I thought it was an allergy to iodine so I opted out for the other option but still end up with rashes. It doesn’t seem life threatening, just really uncomfortable for a week or so. Is this sort of rash other people may experience? Might it be the type of material the needle is made out of that I’m reacting to?

Symptoms: Itchy rash around site of needle poke

Doctor: