weakness/still has weakness; tingling throughout the body, arms legs and torso; no balance; diagnosed with vertigo likely from the equilibrium being off in the middle ear where "crystals can form; she couldn't walk- like a toddler / had to hang on to walls and furniture to walk; really bad dizziness/dizziness was like "being in an earthquake/"horrible" (dizziness); nausea; feels tired/sometimes still "feels tired"; light dizziness,dizziness "was like aswitch went off"; couldn't go to sleep during the night; This spontaneous case was reported by a consumer and describes the occurrence of VERTIGO (diagnosed with vertigo likely from the equilibrium being off in the middle ear where "crystals can form) and GAIT INABILITY (she couldn't walk- like a toddler / had to hang on to walls and furniture to walk) in a 72-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 016A21A and 016A21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included High cholesterol, Drug allergy (Vicodin) and Drug allergy (Codeine). Concomitant products included CALCIUM CARBONATE, COLECALCIFEROL (VITAMIN D 2000) for an unknown indication.   On 02-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 30-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 21-Apr-2021, the patient experienced DIZZINESS (light dizziness,dizziness "was like aswitch went off") and INSOMNIA (couldn't go to sleep during the night). On 22-Apr-2021, the patient experienced VERTIGO (diagnosed with vertigo likely from the equilibrium being off in the middle ear where "crystals can form) (seriousness criterion intervention required), GAIT INABILITY (she couldn't walk- like a toddler / had to hang on to walls and furniture to walk) (seriousness criterion intervention required), ASTHENIA (weakness/still has weakness), PARAESTHESIA (tingling throughout the body, arms legs and torso), BALANCE DISORDER (no balance), DIZZINESS (really bad dizziness/dizziness was like "being in an earthquake/"horrible" (dizziness)), NAUSEA (nausea) and FATIGUE (feels tired/sometimes still "feels tired"). The patient was treated with ONDANSETRON (ZOFRAN [ONDANSETRON]) (oral) ongoing since an unknown date for Vertigo and Nausea, at a dose of 1 dosage form. At the time of the report, VERTIGO (diagnosed with vertigo likely from the equilibrium being off in the middle ear where "crystals can form), GAIT INABILITY (she couldn't walk- like a toddler / had to hang on to walls and furniture to walk), DIZZINESS (light dizziness,dizziness "was like aswitch went off"), ASTHENIA (weakness/still has weakness), PARAESTHESIA (tingling throughout the body, arms legs and torso), BALANCE DISORDER (no balance), INSOMNIA (couldn't go to sleep during the night) and NAUSEA (nausea) outcome was unknown, DIZZINESS (really bad dizziness/dizziness was like "being in an earthquake/"horrible" (dizziness)) had resolved and FATIGUE (feels tired/sometimes still "feels tired") had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In April 2021, Blood test: unknown (Inconclusive) Results not provided but patient's blood work was taken while in the ER. In April 2021, Computerised tomogram: unknown (Inconclusive) Results not provided but patient diagnosed with vertigo.         Treatment administered in the Emergency Room (ER) included unspecified IV anti-vertigo medication and nausea medications.  The patient was discharged from the ER with over the counter motion sickness medication to treat vertigo and nausea, in addition to the oral Zofran.  At the time of the report the patient endorsed that she felt almost normal but that she was still experiencing weakness and sometimes still feels tired.  Company Comment: 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.   Most recent FOLLOW-UP information incorporated above includes: On 23-Jul-2021: Contact information confirmed.; 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.