side effects from Moderna Vaccine; diarrhea; vision issues; balance issues; Could the combo of vaccine and Hetlioz could have cause this reaction; This spontaneous case was reported by a physician and describes the occurrence of VACCINATION COMPLICATION (side effects from Moderna Vaccine) in an elderly male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product TASIMELTEON (HETLIOZ) capsule for Circadian rhythm sleep disorder and Sleep disorder.    The patient's past medical history included Circadian rhythm sleep disorder. Concurrent medical conditions included Blindness, both eyes (impaired level not further specified) and Penicillin allergy. Concomitant products included METFORMIN HYDROCHLORIDE, PIOGLITAZONE HYDROCHLORIDE (ACTOPLUS MET) for an unknown indication.   On an unknown date, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form and TASIMELTEON (HETLIOZ) (Oral) 20 milligram once a day. On an unknown date, the patient experienced VACCINATION COMPLICATION (side effects from Moderna Vaccine) (seriousness criterion hospitalization), DIARRHOEA (diarrhea), VISUAL IMPAIRMENT (vision issues), BALANCE DISORDER (balance issues) and DRUG INTERACTION (Could the combo of vaccine and Hetlioz could have cause this reaction). The patient was hospitalized for 2 days due to VACCINATION COMPLICATION. At the time of the report, VACCINATION COMPLICATION (side effects from Moderna Vaccine), DIARRHOEA (diarrhea), VISUAL IMPAIRMENT (vision issues), BALANCE DISORDER (balance issues) and DRUG INTERACTION (Could the combo of vaccine and Hetlioz could have cause this reaction) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Heart rate: low (Low) Heart rate decreased.  For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered VACCINATION COMPLICATION (side effects from Moderna Vaccine), DIARRHOEA (diarrhea), VISUAL IMPAIRMENT (vision issues), BALANCE DISORDER (balance issues) and DRUG INTERACTION (Could the combo of vaccine and Hetlioz could have cause this reaction) to be possibly related.    No Treatment Medication reported.  Heltilioz was first shipped on 02-Jul-2014.  The causal relationship between Heltlioz and side effects were reported as not related.  Concentration for ACTOPLUS MET in the SD was given as 15-500 milligram..  Company Comment - This case concerns an elderly male patient with no relevant medical history, who experienced the unexpected serious event of Vaccination complication. The event occurred an unknown number of days after the second dose of mRNA-1273 vaccine. The details of the event were not provided. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This case concerns an elderly male patient with no relevant medical history, who experienced the unexpected serious event of Vaccination complication. The event occurred an unknown number of days after the second dose of mRNA-1273 vaccine. The details of the event were not provided. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.