Just the first of the Pfizer vaccine-No reaction at all except arm soreness; This is a spontaneous report received from a contactable reporter(s) (Other HCP). The reporter is the patient.  A 66 year-old female patient received bnt162b2 (BNT162B2), intramuscular, administered in deltoid left, administration date 12Jan2021 10:00 (Lot number: EL3246) as dose 1, single for covid-19 immunisation. Relevant medical history included: "bladder cancer" (ongoing), notes: AE: Bladder cancer, Chemo used for it; "melanoma", start date: Aug2008, stop date: Sep2010, notes: AE: Melanoma; "merkel cell carcinoma", start date: 2011, stop date: 2012, notes: AE: merkel cell carcinoma, Partial removal of R ear; "antihistamine" (unspecified if ongoing). Concomitant medication(s) included: CLARITIN [CLARITHROMYCIN] taken for antiallergic therapy. The following information was reported: PAIN IN EXTREMITY (non-serious), outcome "unknown", described as "Just the first of the Pfizer vaccine-No reaction at all except arm soreness".  Additional Information: Additional Information: Patient wanted to know what to ado about booster as she had cancer but like to take it. Her doctor advised that she could take anti histamine prior to shot & then take chances & got it. Patient did provide information to you regarding the reported adverse event(s) with the use of the product and considered Pfizer product does not had a causal effect to the adverse event. Vaccination Facility Type was hospital. Patient had 1st covid 19 vaccine on 12Jan2021 without any problems. The second dose was given on 02Feb2021 around 1030. Patient was leaving after waiting my 15 minutes and heart started to race. Heart rate was initially 130. My face became hot and flushed. Felt tingling in her head and down left arm. Was given a clarity and then transported to emergency room. The symptoms subsided in about 20minutes. Oxygen saturation and BP were normal slight shortness of breath. The patient described all the signs and symptoms of the anaphylactic reaction as: blood pressure (BP) initial 144/59 and Respiratory rate was 18. Heart Rate (HR) was 130 Pulse or on 2L oxygen, oxygen saturation was 98%. The 2nd time anaphylactic reaction, the BP was 120/64 hear rate was 84, oxygen saturation was 99%. The time course of the anaphylactic reaction was described as follows: 10:30 vaccine given at 10: 45-10: 50 HR increase 130 face flushed and with numbness of head and Left arm. Claritin (antihistamine) given along with peptid. Numbness continued and sent to emergency room (ER). The patient sat in ER for 3 hours and the numbness lasted 30minutes. O2 was placed on, and the patient's physical condition were stable. Slight SOB (Short of breath) noted when heart rate elevated. The patient was hospitalized (just in emergency department). The patient was not admitted to an Intensive Care Unit. Multiorgan involvement was yes which included respiratory, respiratory distress, tachypnoea, short of breath. There was no bilateral wheeze (bronchospasm), stridor, upper airway swelling involved. There was no increased use of accessory respiratory muscles. There was no recession, cyanosis, grunting, dry cough, hoarse voice. The patient had difficulty breathing (without wheeze or stridor), she felt slight tightness in chest making her difficulty to breath. There was no sensation of throat closure, sneezing, rhinorrhea, measured hypotension, shock. There was cardiovascular disorder was involved. She had tachycardia with heart rate elevated >120. There was no capillary refill time> 3 second, no reduced central pulse volume, no decreased level of consciousness, loss of consciousness, dermatological/mucosal, generalized urticaria (hives). The patient experienced generalized erythema with face was beet red and hot. There was no angioedema (not hereditary) involved, no generalized pruritus with skin rash involved, no generalized pruritus without skin rash involved, no localized injection site urticaria involved, no red and itchy eyes involved. Generalized prickle sensation was present in the patient. She felt numbness and prickle sensation of head and one arm. The patient had no gastrointestinal disorder, had no diarrhea, no abdominal pain, no nausea, no vomiting. The patient asked if she should get the booster shot. The reported events required the initiation of new medication or other treatment or procedure and the patient just had one time dose of Antihistamine and oxygen. The following laboratory tests or diagnostic studies was performed. Mast cell tryptase, Immune makers (e.g. total IgE levels), Complement activation test, Hematology on 02Feb2021 with results of NH-12.6, 39.5 WBC (Reference Ranges: Normal 5.8), Clinical chemistry on 02Feb2021. And other relevant tests were performed on 02Feb2021, EKG with results of normal, Na-141, K-3.8, Cl-104, Co2-28, BUN-13, Creatine-0.6, Glucose-104. Past Medical History The patient was taking any medications routinely prior to the event being reported: Yes; Depakote, Lipitor, ASA. Patient received the first of the the Pfizer vaccine- No reaction at all except arm soreness. Patient did not received any recent vaccine for SARS-CoV2 other than Pfizer-BioNTech COVID-19 Vaccine prior to the event being reported.  Patient received no any other vaccines around the time of Pfizer-BioNTech COVID-19 Vaccine vaccination.  No follow-up attempts are possible. No further information is expected.