ended up getting poison ivy after the booster dose; her triglycerides were high; one of her thyroids was a little low; This is a spontaneous report from a contactable consumer (patient) from a Pfizer sponsored program. A 74-year-old female patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE lot number: ER8734) via an unspecified route of administration, administered on the left arm on 25Sep2021 (at the age of 74-year-old) as dose 3 (booster), single for COVID-19 immunization. Medical history included allergy and COVID-19 back in Jul2020. The patient's concomitant medications were not reported. The patient previously received first dose of Comirnaty on 29Jan2021 (LOT: EL8982, injected in her left arm) and second dose of Comirnaty on 19Feb2021 (LOT: EL9267, injected in her right arm) for COVID-19 immunisation. Patient ended up getting poison ivy after the booster dose and was prescribed 21 tablets of Methylprednisolone 4mg. She stated that she received the booster dose of the Pfizer Covid-19 vaccine because of her age, not because of her immune system. Patient was asking if the Methylprednisolone interacts with the Pfizer Covid-19 vaccine and should you not take it? Patient said she saw her primary care provider the other day when she didn't know she had poison ivy, so the reaction wouldn't be on her record, and she was actually not the one who prescribed the Prednisone, clarified later to Methylprednisolone. She said she had been tested for COVID and had tested negative, then her family got together for the 04Jul, and her son in law thought he had a sinus and ear infection, but it was COVID and all nine of them got it. She said it took a while to get over it, so she wanted to try to prevent getting it again by getting the vaccine. Poison Ivy: Caller said she was tested prior to getting the shot. She said she was always so careful with gloves and everything. She said she got her vaccine dose, then saw her internist on Monday but she didn't think it would be a problem, and she already had a Medpak on hand since they go to a cabin in the boonies, which her husband's doctor wrote it for them so they could have it if they needed it, they would have it. She said she didn't talk about poison ivy with her then. She said that the poison ivy has been the worst case she has ever had, so she didn't know if having had the booster dose made her more prone or not able to fight off the poison ivy. She said she called to ask should she not take the dose pack now, since she can just get thru this, it was just the fact that this is the worst case she has ever had, it has spread like crazy. She said she wondered if having had Pfizer vaccine had anything to do with her not being able to fight off poison ivy. She said she was curious if Pfizer had any research or people complaining about this, or if maybe it is just a coincidence. AE Treatment: Caller said she has treated the poison ivy with nothing but Benadryl spray, clarified to generic Relief Spray or Diphenhydramine Hydrochloride 2%. She said she has used it probably several times a day to treat the poison ivy. She says that the poison ivy has been progressive stuff, it was not there when she got the injection then several days later or two days later it was on her neck and forehead and further down on her leg, it was really weird, without her being in further contact with anything. Investigations: Caller says she recently had lab tests that said her triglycerides were high and one of her thyroids was a little low, but everything else was within normal limits, so she doesn't think any of those are significant for her immune response. Outcome of the events was unknown.  Follow-up attempts are completed. No further information is expected.