Allergies and itching; Red rashes on face and neck; Mast cells disease; Inflammation of the stomach; Allergies and itching; Palpitations; Diarrhea; Abdominal cramping; Red/Itchy eyes; Red/Itchy eyes; Sneezing/runny nose; Sneezing/runny nose; Difficulty breathing; Difficulty swallowing; Prickling/tingling; Numbness; Feeling hot; Flushing; Cough; Chills; This spontaneous case was reported by a consumer and describes the occurrence of ALLERGY TO VACCINE (Allergies and itching), RASH ERYTHEMATOUS (Red rashes on face and neck), WHITE BLOOD CELL DISORDER (Mast cells disease), GASTRITIS (Inflammation of the stomach) and PRURITUS (Allergies and itching) in a 79-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 042L204 and 023MO4) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included Redness and Trembling. Concurrent medical conditions included Small intestinal bacterial overgrowth (SIBO).   On 26-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 23-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date, the patient experienced ALLERGY TO VACCINE (Allergies and itching), RASH ERYTHEMATOUS (Red rashes on face and neck), WHITE BLOOD CELL DISORDER (Mast cells disease), GASTRITIS (Inflammation of the stomach), PRURITUS (Allergies and itching), PALPITATIONS (Palpitations), DIARRHOEA (Diarrhea), ABDOMINAL PAIN (Abdominal cramping), EYE PRURITUS (Red/Itchy eyes), OCULAR HYPERAEMIA (Red/Itchy eyes), SNEEZING (Sneezing/runny nose), RHINORRHOEA (Sneezing/runny nose), DYSPNOEA (Difficulty breathing), DYSPHAGIA (Difficulty swallowing), PARAESTHESIA (Prickling/tingling), HYPOAESTHESIA (Numbness), FEELING HOT (Feeling hot), FLUSHING (Flushing), COUGH (Cough) and CHILLS (Chills). At the time of the report, ALLERGY TO VACCINE (Allergies and itching), RASH ERYTHEMATOUS (Red rashes on face and neck), WHITE BLOOD CELL DISORDER (Mast cells disease), GASTRITIS (Inflammation of the stomach), PRURITUS (Allergies and itching), PALPITATIONS (Palpitations), DIARRHOEA (Diarrhea), ABDOMINAL PAIN (Abdominal cramping), EYE PRURITUS (Red/Itchy eyes), OCULAR HYPERAEMIA (Red/Itchy eyes), SNEEZING (Sneezing/runny nose), RHINORRHOEA (Sneezing/runny nose), DYSPNOEA (Difficulty breathing), DYSPHAGIA (Difficulty swallowing), PARAESTHESIA (Prickling/tingling), HYPOAESTHESIA (Numbness), FEELING HOT (Feeling hot), FLUSHING (Flushing), COUGH (Cough) and CHILLS (Chills) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood immunoglobulin E: 3 (abnormal) IU/ml results confirmed on dilution. On an unknown date, Histamine level: high (High) High.         The patient did not had any history of anaphylaxis, hypersensitivity, asthma and hay fever.  No concomitant medications were reported.  No treatment medication were reported.   Most recent FOLLOW-UP information incorporated above includes: On 03-Aug-2021: Follow up information received contains significant information. Added Lab data, current condition, additional adverse events were added. Added Batch number, Updated start date for both the dosage of the suspect vaccination. Patient's race information were updated.; Sender's Comments: Very limited information regarding the events has been provided at this time.  Further information is not expected.