Received Dec 1, 2025
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| COVID19 | COVID19 (COVID19 (MODERNA MNEXSPIKE)) | MODERNA | UNK | — | IM |
palpitations/heart flutters/continuous flutters; continuous flutters; felt miserable; a lack of energy and appetite; His arm aching; Lack of energy; he then began to feel achy all over, with every bone; This spontaneous case was reported by a consumer and describes the occurrence of PALPITATIONS (palpitations/heart flutters/continuous flutters) and CARDIAC FLUTTER (continuous flutters) in a 75-year-old male patient who received mRNA-1273.251 (Spikevax LP.8.1 PFS) for COVID-19 prophylaxis. The occurrence of additional non-serious events is detailed below. Suspect product included Pre-filled Syringe injection for COVID-19 prophylaxis. Previously administered products included for Product used for unknown indication: Influenza vaccine (flu shot within 4 weeks.). Past adverse reactions to the above products included No adverse effect with Influenza vaccine. On 20-Nov-2025, the patient received dose of mRNA-1273.251 (Spikevax LP.8.1 PFS) (Intramuscular use) 1 dosage form. On an unknown date, the patient started Pre-filled Syringe (unknown route) at an unspecified dose. In November 2025, the patient experienced PALPITATIONS (palpitations/heart flutters/continuous flutters) (seriousness criterion medically significant), CARDIAC FLUTTER (continuous flutters) (seriousness criterion medically significant), FEELING ABNORMAL (felt miserable), DECREASED APPETITE (a lack of energy and appetite), PAIN IN EXTREMITY (His arm aching), ASTHENIA (Lack of energy) and MYALGIA (he then began to feel achy all over, with every bone). In November 2025, FEELING ABNORMAL (felt miserable), DECREASED APPETITE (a lack of energy and appetite) and ASTHENIA (Lack of energy) had resolved. At the time of the report, PALPITATIONS (palpitations/heart flutters/continuous flutters), PAIN IN EXTREMITY (His arm aching) and MYALGIA (he then began to feel achy all over, with every bone) had not resolved and CARDIAC FLUTTER (continuous flutters) outcome was unknown. DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In November 2025, Heart rate: Low heart rate and abnormal heart rhythm.. The action taken with mRNA-1273.251 (Spikevax LP.8.1 PFS) (Intramuscular use) was unknown. Concomitant medication was not provided. The patient was 75 years old and had always been in good shape. It was reported that the patient had felt fine for about 12 hours after receiving the vaccine and had not experienced any symptoms initially. It was stated that he later began to feel achy all over, with pain in every bone and his arm. According to the reporter, he had experienced a lack of energy and appetite and had felt miserable, which lasted for approximately 12 to 24 hours. Also mentioned that his Apple Watch and Holter monitor, which were used to check for atrial fibrillation, had indicated heart flutters, palpitations, and a low heart rate. She added that the cardiologist had called twice the previous night because his heart had been experiencing continuous flutters and a low heart rate. It was unknown if the patient experienced any additional symptoms or events. The recommendation was to start blood thinners on 25-Nov-2025 and to schedule a shock treatment for Friday due to the abnormal heart rhythm.; Reporter's Comments: The benefit-risk relationship of product is not affected by this report.
Test Date: 202511; Test Name: Heart rate; Result Unstructured Data: Low heart rate; Test Date: 202511; Test Name: Heart rate; Result Unstructured Data: abnormal heart rhythm.