POSSIBLE ALLERGIC REACTION (Received second pfizer vaccine yesterday and developed angioedema with tongue involvement - hospitalized.    Admission Date: 8/31/2021 Discharge Date: 09/04/2021 Presented to ED - transferred and admitted to hospital.  60-year-old woman significant past medical history of tonsillar squamous cell carcinoma with resection on immunotherapy as well as oropharyngeal dysphasia presents emergency department today with increasing swelling of her lips and tongue symptoms 1st started 12 hours after receiving Pfizer vaccination as a booster no problems with the other vaccinations.  This morning despite taking Benadryl last night noticed increasing swelling although very gradually worsening swelling in this prompted presentation is not on any ACE-inhibitor medications or arbs has never had a reaction like this before I do favor angioedema as a cause for her symptoms here today although allergic reaction is very possible in will treat with Benadryl, Pepcid, Solu-Medrol patient is also febrile emergency department but denies any clear source on history with recent COVID-19 vaccination I feel is most likely related to this.  PRESENTING PROBLEM: Angioedema of lips, sequela  Angioedema, initial encounter  HOSPITAL COURSE: 60 year old female with history of tonsillar squamous cell carcinoma status post surgical resection, currently on treatment with immunotherapy (nivolumab), HTN, and oropharyngeal dysphagia who is admitted to the ICU for management of angioedema requiring intubation and mechanical ventilation following COVID vaccination administration. She presented initially to the ED with increasing swelling of her tongue and lips which first started about 12 hours after receiving her 3rd Pfizer booster vaccination on 8/30/2021. Pt reportedly had no problems or adverse effects with her first two vaccinations. The morning after the 3rd vaccination, she noted increasing swelling despite having taken Benadryl the night before. She noted to the ED provider that she had never had a reaction to this before, and that she does not take chronic ACE inhibitor or ARB medication. There were concerns for airway protection, and the decision was made to intubate the pt. Intubation was performed in the ED with the assistance of Anesthesia. Intubation was initially attempted with the fiberoptic bronchoscope, but was unsuccessful. Anesthesia was eventually able to intubate the pt orotracheally with the Glidescope. The view was not easy to obtain due to secretions and edema, but a 7.0 ETT was finally passed successfully. Pt was otherwise treated with Benadryl, Pepcid, and IV solumedrol.   CT showed large ventral abdominal wall hernia with new large thick walled cystic mass measuring 19cm - General surgery and Interventional radiology consulted plan to work up as outpatient.  Extubated 9/2.   Transferred to the floor to the IM service. There continued to improve and was weaned off of oxygen. Continued prednisone taper per ICU recs. Will send on zyrtec as well. SLP evaluated- patient was able to transition to moist ground and thin liquids diet. Providing BMX at d/c. HH SLP to follow at home as well. At this time she is stable, improved, and ready for d/c home.