Patient experienced an anaphylactic reaction to the COVID-19 Pfizer vaccine.  (difficulty breathing, swelling of face and throat, rash - within 4 hours; emergency treatment sought)  Immediately after administering the COVID-19 booster dose - patient complained of some tightness is the throat and was shaking.  Office Notes:   "He was feeling some tightness in his throat when I arrived and was talking to him.  He was not having any respiratory distress.  We examined the heart lungs and he appeared to have a regular rate and rhythm along with normal breath sounds.  No wheezing audible. I asked him if he had a history of anxiety which he stated he did. I also asked if he had any reaction to the 1st or 2nd COVID-19 vaccinations and he stated he did not. We discussed that this could just be an anxiety provoked reaction. I reassured the patient that everything looks good and sounds good Obviously we cannot examine the inside of his throat to look at his airway but I advised him to drink some water while he waited the 15 minutes he was also sent after receiving the COVID vaccination. I checked on the patient multiple times throughout the 15 minutes.  Each time I spoke with him his symptoms were improving.  We discussed that if he was having an anaphylactic reaction the water would not improve the symptoms and it would have worsened.  I gave him reassurance that this is likely just related to anxiety and there is no indication for us to call EMS or inject steroids at this time.  He was advised that if his symptoms were worsening he should call 911 for further evaluation.  Patient in agreement the plan."  Telemedicine appointment 2 hours after vaccine - "Wheezing, some dyspnea, throat feels tight after COVID 19 vaccination 2 hours ago. I have escalated patient to in person at the ER. His parents will drive him now."  When to Emergency Department - 4.11.22 - DIAGNOSIS at time of disposition: 1. Anaphylaxis due to COVID-19 vaccine.  HISTORY OF PRESENT ILLNESS: Patient is a 25-year-old male with the chief complaint of a possible allergic reaction. Patient explains that this morning he received his booster dose of the Pfizer COVID-19 vaccination. Patient describes that immediately after the shot he noticed chest tightness and sore throat, describing this as tight. He notified his PCP of his symptoms who told him they were likely related to anxiety and told him to take a dose of his anxiety medication when he returned home. Patient describes that upon returning home he noticed continued chest tightness along with wheezing. He also describes a rash to his neck, abdomen, and back. Patient notes that he took a dose of Benadryl and Ativan around 1130. He notes that he was not feeling particularly anxious prior to the vaccination. He received both doses of the Pfizer COVID-19 vaccination in March 2021 and April 2021 without similar reaction. He notes that he tested positive for COVID-19 February 2022. Denies fever. He reports that he does have peanut allergies and has an EpiPen at home. 1336:  On exam he does have some bilateral expiratory wheezing, rash on his back neck and arms with some urticaria where he has scratched the rash.  Oropharynx is clear, voice is normal and there is no oral swelling.  Some erythema to the posterior pharynx noted I did order IV Solu-Medrol, IV Benadryl and Pepcid, fluids and albuterol for wheezing.  I do not feel patient needs EpiPen at this time. 1338:  Patient's rash was worsening, he started having swelling around his eyes.  He continued to have wheezing.  We decided to give him epinephrine and move him to a monitored room.  Patient was placed on a cardiac monitor, administered epinephrine will continue to monitor his symptoms. 1620:  Patient was reassessed around 3:30 p.m., his rash had resolved, he was having no sensation of throat swelling, wheezing had resolved and he fell back to baseline.  Will continue to monitor the patient until around 4:30 p.m  1636:   Patient reassessed again, no recurrent symptoms, no wheezing, pulse ox 99%, no facial swelling, no rash.  I did offer to observe the patient for an hour or 2 longer but they were comfortable going home at this point in time with no recurrent symptoms.  I will prescribe prednisone 40 mg for 2 more days, have him continue Benadryl every 6 hours and follow up with this with his doctor.  He has an EpiPen at home that is not expired and he is educated about symptoms that require using it and calling 911. He is welcome to come back with any new or worsening symptoms.  He is advised never to receive a COVID-19 vaccine again due to the severe allergy.  + elevated BP - to be evaluated by PCP.