GRAVES DISEASE; ATRIAL FIBRILLATION; SUBCENTIMETER THYROID NODULES IN THE RIGHT AND LEFT THYROID LOBE; CONSTELLATION OF NONSPECIFIC SYMPTOMS WITHIN 24 TO 48 HOURS AFTER VACCINATION; This spontaneous report received from a consumer via media via company representative in addition to information received from received from literature. This report concerned a 68 year old female. The objective of this study was to describe COVID-19 vaccines, either mRNA-based (Moderna) or non-mRNA-based (Johnson & Johnson), can cause Graves' disease. The clinical manifestations are similar to Graves' disease but without ocular manifestations. The patient's height, and weight were not reported. The patient's concurrent conditions included: normal thyroid function, and other pre-existing medical conditions included: Patient did not have any previous autoimmune thyroiditis or previous history of thyroid disease. On 25-FEB-2019, Laboratory data included: Thyroid stimulating hormone (NR: 0.45 - 4.5) 0.77 miU/mL which was normal thyroid function.  The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of administration, batch number: unknown and expiry: unknown) dose was not reported, 1 total, administered on 06-MAR-2021 for prophylactic vaccination. The batch number was not reported and has been requested. No concomitant medications were reported.  On 07-MAR-2021, the patient developed a constellation of nonspecific symptoms within 24 to 48 hours after receiving the vaccine. On 09-MAR-2021, Laboratory data included: Free T4 (NR: 0.82 - 1.77) 1.41 ng/dL, Thyroid stimulating hormone 0.23 m[iU]/mL, and WBC (NR: 3.4 - 10.8) 4.4 10^3/uL. After one month in APR-2021, Laboratory data included: Laboratory test (NR: not provided) 14.3 IU/L, 5.84 IU/mL, Laboratory test (NR: not provided) 14.3 IU/L, 5.84 IU/mL, and TSH (NR: 0.45 - 4.5) less than 0.01 mIU/ml. On 07-APR-2021, patient was re-evaluated and was found to be in atrial fibrillation. The patient's history was most remarkable for a relative paucity of hyperthyroid symptoms and no eye signs of Graves' disease. On 07-APR-2021, the patient had a suppressed Thyroid stimulating hormone, Free T4 3.6 ng/dl (NR: 0.6-1.3), and Free T3 13.8 pg/ml (NR: 2.5-3.9). Thyroid ultrasound showed subcentimeter thyroid nodules in the right and left thyroid lobe that corresponded to the area with decreased technetium uptake on the scan. A technetium thyroid scan showed inappropriately normal uptake bilaterally with a region of relative photon deficiency in the right and left thyroid lobes due to nodules. On an unspecified date, the patient experienced Graves disease. The patient was started on methimazole, beta-blocker, and apixaban due to the new onset of atrial fibrillation. Treatment medications (dates unspecified) included: methimazole, beta-blocker, and apixaban. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The outcome of the graves disease, atrial fibrillation, subcentimeter thyroid nodules in the right and left thyroid lobe and constellation of nonspecific symptoms within 24 to 48 hours after vaccination was not reported. The authors concluded that the overall incidence of Graves' disease after the COVID-19 vaccination is very low, thus the benefit of immunization overweighs the negligible risk. The clinicians must be vigilant for diagnosis of hyperthyroidism, including Graves' disease in patients presenting with overactive thyroid signs or symptoms after recent COVID-19 vaccination. This report was serious (Other Medically Important Condition).  Additional information was received from healthcare professional via literature article on 09-MAY-2022. The following information was updated and incorporated into the case narrative: Medically confirmed selected as yes, invalid yes deselected, reporter's added, lab data (TSH Receptor Ab, Thyroid peroxidase Ab and TSH) were added.; Sender's Comments: The follow up add: Medically confirmed selected as yes, invalid yes deselected, reporter's added, lab data (TSH Receptor Ab, Thyroid peroxidase Ab and TSH). This new information does not change prior causality assessment.  20220449219- COVID-19 VACCINE AD26.COV2.S-atrial fibrillation. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s). Therefore, this event(s) is considered unassessable. 20220449219- COVID-19 VACCINE AD26.COV2.S-Graves disease. The event(s) has an unknown/unclear temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s). Therefore, this event(s) is considered unassessable.