Dehydrated; ear ringing/Tinnitus; She was in bed for 3 days because of her symptoms; Cannot function at her work; Vertigo; Falling because of the dizziness; She has been falling because of the dizziness; Arm pain; nausea/throwing up 4 times a night; cannot retain food or fluids/could not keep down bread and soup; Fever; This spontaneous case was reported by a consumer and describes the occurrence of DEHYDRATION (Dehydrated) in a 38-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.    On an unknown date, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, the patient experienced DEHYDRATION (Dehydrated) (seriousness criterion medically significant), TINNITUS (ear ringing/Tinnitus), MOBILITY DECREASED (She was in bed for 3 days because of her symptoms), IMPAIRED WORK ABILITY (Cannot function at her work), VERTIGO (Vertigo), FALL (Falling because of the dizziness), DIZZINESS (She has been falling because of the dizziness), VACCINATION SITE PAIN (Arm pain), NAUSEA (nausea/throwing up 4 times a night), VOMITING (cannot retain food or fluids/could not keep down bread and soup) and PYREXIA (Fever). The patient was treated with PROMETHAZINE (PHENERGAN [PROMETHAZINE]) for Adverse event, at an unspecified dose and frequency and DIAZEPAM (VALIUM) for Adverse event, at an unspecified dose and frequency. At the time of the report, DEHYDRATION (Dehydrated), TINNITUS (ear ringing/Tinnitus), MOBILITY DECREASED (She was in bed for 3 days because of her symptoms), IMPAIRED WORK ABILITY (Cannot function at her work), VERTIGO (Vertigo), FALL (Falling because of the dizziness), DIZZINESS (She has been falling because of the dizziness), VACCINATION SITE PAIN (Arm pain), NAUSEA (nausea/throwing up 4 times a night), VOMITING (cannot retain food or fluids/could not keep down bread and soup) and PYREXIA (Fever) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Body temperature: increased (High) Fever.         No Concomitant medication was reported. Treatment medication included steroids for a  adverse event.  The patient experienced fever, nausea, arm pain, ear ringing, tinnitus, vertigo, "and all that." She was in bed for 3 days because of her symptoms. She had been throwing up 4 times a night due to the nausea and vertigo. She cannot function at her work and has been falling because of the dizziness. She had not been able to eat and retain food. She had been to the emergency department at least 3 times because she cannot retain food or fluids, becomes dehydrated, and needs IV fluids. She could not retain bread and soup yesterday, because she couldn't swallow and would choke. She had received a brain MRI (Magnetic resonance imaging), CT (Computed tomography) scans of her head. Nobody can figure out what was wrong and they keep blaming it on the side effects of the shot. Her most recent ER visit was last night. She has not been hospitalized for her symptoms because there are not beds available.  This case concerns a 38-year-old, female patient with no relevant medical history reported, who experienced the unexpected event of dehydration. The event occurred on an unknown number of days after the second dose of mRNA-1273. The rechallenge was not applicable since the event happened after the second dose. The benefit-risk relationship of mRNA-1273 in not affected by this report.   This case was linked to MOD-2021-346429 (Patient Link).; Sender's Comments: This case concerns a 38-year-old, female patient with no relevant medical history reported, who experienced the unexpected event of dehydration. The event occurred on an unknown number of days after the second dose of mRNA-1273. The rechallenge was not applicable since the event happened after the second dose. The benefit-risk relationship of mRNA-1273 in not affected by this report.