1022 - Patient received her 1st Pfizer vaccine by RN.  She noted a history of vasovagal syncope to needles in the past (did not seem like it was complete syncope to all needle sticks per RN).  RN offered for her to lie down, but she said she felt ok sitting.  She did not endorse any history of severe allergies or reactions to injectables in the past; she was asked the necessary questions prior to vaccination.  We later learned she has Crohn?s and is on immunosuppressant Imuran for this disorder.  1023ish ? walked to checkout area  1025 - While sitting at the checkout registering for her second shot she started to feel faint and checkout staff called for help  1026 - RNs were getting the BP cuff on her. She appeared obtunded and slouching in her chair- eyes closed. Gentle sternal rub and she was able to open her eyes and tell us what her name was and ask to call her dad. BP 90/58. Cold cloths placed on her neck. Continuous pulse ox monitor placed, showing 99%.  1030 - Still drowsy and diaphoretic. Able to tell us that "she passes out when she gets shots" C/O nausea and vomited. Still in and out of awareness. NP is site coordinator is now present and suggests taking patient by wheelchair to safer and more private area for evaluation in SR Room.  Patient able to stand and transfer to wheelchair, which we did slowly and carefully.  1034 ? Now in safer and more private area SR room with NP and RN and Dr. Firemen are here and assessing the scene with medic assessing patient. Ambulance in route, about 5 - 10 minutes out per radio communication.  Checking BP every 2  minutes.  Now is 68/44. C/O nausea and vomited. Pulse ox won?t pick up.  Patient with decreasing LOC, eyes rolling back in head, unable to maintain posture seated, and not able to describe symptoms to us (unknown if she felt itchy but no obvious cutaneous manifestations).  Unable to visualize oropharynx.  1037- BP 57/40. NP administered Epi pen 0.3 mg dose to L lateral thigh due to s/s of systemic allergic reaction/anaphylaxis including 3 known body systems: hypotension (cardiovascular), vomiting (GI), and decreased LOC (neuro). No IV fluids immediately available but were preparing to obtain.  Staff getting cot for patient to lie down.  Provider spoke with her mom on the phone and informed her of event. Mom confirmed that she has often before passed out with vaccines and blood draws. Dad was on his way to center and rerouted to ER.  1038 - BP 68/45 Talking to medics and able to tell them she ate breakfast and that she has a hx of Crohn's and takes a monthly injection. Informed provider that her dad was on his way. EMS team here to transport to ER.  We were preparing to put her on a cot so help with her blood pressure/blood flow when she started to stabilize and EMS arrived with stretcher.    1040 - BP 97/53.  Patient is now alert and talking to us.  Says she has had syncope in the past ?but never anything like this.?    1041 - BP 115/53. Patient still alert and talking.  Oriented x 3.  1042 - Transported to ER by EMS ambulance on stretcher.  DEBRIEF: Somewhat atypical (no obvious cutaneous manifestations) and rapid, severe reaction.  Ddx vasovagal vs anaphylaxis.  Response to epi consistent with anaphylaxis reversal.  Perhaps immunosuppressant medication contributed to severity and rapidity of reaction.