It was discovered yesterday that my thyroid levels are TOO LOW, meaning that I may now have hyperthyroidism; Absolutely miserable as if I had a horrible flu type illness; Unable to eat; Sore throat; Malaise, just laid in bed for days.; Body aches; Headache; I awoke with a fever of over 102 degrees; This spontaneous case was reported by a consumer and describes the occurrence of HYPERTHYROIDISM (It was discovered yesterday that my thyroid levels are TOO LOW, meaning that I may now have hyperthyroidism) in a 51-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 019B21A and 011A21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Allergic reaction to analgesics (CODEINE), Penicillin allergy (PENICILLIN), Drug allergy (BUTALBITOL), Drug allergy (VIDODIN), Drug allergy (OXYCODONE,), Drug allergy (HYDROCODONE.), Trauma (Soft tissue damage permanent, 15 fracture including 3 spine, shattered clavicle) since 05-Jun-2019, Hypertension since 2000, Hypothyroidism (went from hypo to hyperthyroid in less than six months time) since 1995, Movement disorder since 05-Jun-2019 and Brain injury since 05-Jun-2019.   On 03-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 31-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 31-Mar-2021, the patient experienced INFLUENZA LIKE ILLNESS (Absolutely miserable as if I had a horrible flu type illness), FEEDING DISORDER (Unable to eat), OROPHARYNGEAL PAIN (Sore throat), MALAISE (Malaise, just laid in bed for days.), MYALGIA (Body aches), HEADACHE (Headache) and PYREXIA (I awoke with a fever of over 102 degrees). On an unknown date, the patient experienced HYPERTHYROIDISM (It was discovered yesterday that my thyroid levels are TOO LOW, meaning that I may now have hyperthyroidism) (seriousness criterion medically significant). On 07-Apr-2021, INFLUENZA LIKE ILLNESS (Absolutely miserable as if I had a horrible flu type illness), FEEDING DISORDER (Unable to eat), OROPHARYNGEAL PAIN (Sore throat), MALAISE (Malaise, just laid in bed for days.), MYALGIA (Body aches), HEADACHE (Headache) and PYREXIA (I awoke with a fever of over 102 degrees) had resolved with sequelae. At the time of the report, HYPERTHYROIDISM (It was discovered yesterday that my thyroid levels are TOO LOW, meaning that I may now have hyperthyroidism) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 31-Mar-2021, Body temperature: 102 (High) 102 degree. On an unknown date, Blood thyroid stimulating hormone: low (Low) Too Low.         No concomitant and treatment medication were provided.  Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded. Further information has been requested.   This case was linked to MOD-2021-037324 (Patient Link).; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded. Further information has been requested.