This spontaneous case was reported by a consumer and describes the occurrence of SINUS TACHYCARDIA (sinus tachycardia), DYSPNOEA (short of breath), LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (My normal activities have been impacted like gardening, running the vacuum, cooking, putting up groceries or dishes), WEIGHT DECREASED (Burned more calories) and VACCINATION COMPLICATION (Laid on couch) in a 51-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 046C21A and 046C21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Drug allergy (Sulfa allergy).   On 03-Sep-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 01-Oct-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 01-Oct-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced VACCINATION SITE PAIN (sore arm). On 02-Oct-2021, the patient experienced SINUS TACHYCARDIA (sinus tachycardia), VACCINATION COMPLICATION (Laid on couch), DIZZINESS (light headed), MYALGIA (body aches), PYREXIA (fever) and CHILLS (chills). On 03-Oct-2021, the patient experienced RASH (rash that went from under bra to waist line then spread up chest to neck line to bottom part of hair line and shoulders/At the hospital, I noticed that I had developed a rash / red flushing around my midsection). On 12-Oct-2021, the patient experienced DYSPNOEA (short of breath) and LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (My normal activities have been impacted like gardening, running the vacuum, cooking, putting up groceries or dishes). On an unknown date, the patient experienced WEIGHT DECREASED (Burned more calories). The patient was treated with POTASSIUM for Adverse event, at an unspecified dose and frequency and MAGNESIUM for Adverse event, at an unspecified dose and frequency. At the time of the report, SINUS TACHYCARDIA (sinus tachycardia) had not resolved, DYSPNOEA (short of breath), LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (My normal activities have been impacted like gardening, running the vacuum, cooking, putting up groceries or dishes), WEIGHT DECREASED (Burned more calories), VACCINATION COMPLICATION (Laid on couch), DIZZINESS (light headed) and VACCINATION SITE PAIN (sore arm) outcome was unknown, RASH (rash that went from under bra to waist line then spread up chest to neck line to bottom part of hair line and shoulders/At the hospital, I noticed that I had developed a rash / red flushing around my midsection) had resolved and MYALGIA (body aches), PYREXIA (fever) and CHILLS (chills) was resolving.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 02-Oct-2021, Heart rate: 11o (abnormal) Abnormal, 120 (abnormal) abnormal and 135 (abnormal) abnormal. On 03-Oct-2021, Heart rate: 105-108 (abnormal) abnormal and about 77 (normal) After putting on drip to lower heart rate.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered SINUS TACHYCARDIA (sinus tachycardia), DYSPNOEA (short of breath), LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (My normal activities have been impacted like gardening, running the vacuum, cooking, putting up groceries or dishes), WEIGHT DECREASED (Burned more calories), VACCINATION COMPLICATION (Laid on couch), DIZZINESS (light headed), RASH (rash that went from under bra to waist line then spread up chest to neck line to bottom part of hair line and shoulders/At the hospital, I noticed that I had developed a rash / red flushing around my midsection), VACCINATION SITE PAIN (sore arm), MYALGIA (body aches), PYREXIA (fever) and CHILLS (chills) to be possibly related.    Patient went to the Emergency Room on 03-OCT-2021 where tests were conducted and she was released with a diagnosis of sinus tachycardia. They performed an ECG, CT Scan, EKG, Chest  X-ray, Basic metabolic panel, Troponin T, D-Dimer, Complete blood count with differential.  Patinet took a cold shower, drank cold water, performed deep breathing exercises, and held her breath for a beat before exhaling as attempts to lower my heart rate. These attempts would work just for a very few moments.  The patient also stated that just take potassium and magnesium supplement  No concomitant medications were reported  Patient was given IV drip to lower my heart rate.   This case was linked to MOD-2021-344291 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 12-Oct-2021: Follow-up information received on12-OCT-2021, Patient demographic details , Medical history , event outcome and additional events updated.; Sender's Comments: This case concerns a 51-year-old non-pregnant female with a BMI of 29.3, with no previous relevant medical history, who experienced the unexpected non serious AESI event Sinus tachycardia and other expected non serious events after the second dose of a proper schedule of administration (28 days between doses) of Moderna COVID-19 vaccine. The diagnosis of Sinus tachycardia was made in an ER room after performing ECG, CT Scan, EKG, Chest X-ray, Basic metabolic panel, Troponin T, D-Dimer and Complete blood count. Heart rate was between 105 to more than 130 bpm. The patient did not required hospitalization. The events´ onset was 1 day after the second dose. At the time of the report the event Sinus tachycardia was ongoing. For the event Sinus tachycardia the rechallenge is not applicable as per it was reported after the second dose and no further doses are expected. The benefit-risk relationship of Covid19 Moderna vaccine is not affected by this report.