Condition aggravated; chest pain; Intermittent Tachycardia; heart palpitation; lightheadedness; Very Tired; Sore Injection; This spontaneous case was reported by a consumer and describes the occurrence of TACHYCARDIA (Intermittent Tachycardia) in a 39-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 023C21A and 092B21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Nerve pain (Since 3.5 years) in 2017, Drug allergy (Allergy to Codine), Drug allergy (Allergy to dimatap (old formulation)), Drug allergy (Allergy to imetrix) and Vertigo (Definite increase in lightheaded and dizzy) since 2016. Concomitant products included GABAPENTIN for Nerve pain.   On 05-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 03-May-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 05-Apr-2021, the patient experienced FATIGUE (Very Tired) and VACCINATION SITE PAIN (Sore Injection). On 20-Apr-2021, the patient experienced TACHYCARDIA (Intermittent Tachycardia) (seriousness criterion medically significant), PALPITATIONS (heart palpitation), DIZZINESS (lightheadedness) and CHEST PAIN (chest pain). On an unknown date, the patient experienced CONDITION AGGRAVATED (Condition aggravated). The patient was treated with METOPROLOL for Heart rate, at a dose of 25 milligram. On 06-Apr-2021, FATIGUE (Very Tired) and VACCINATION SITE PAIN (Sore Injection) had resolved. At the time of the report, TACHYCARDIA (Intermittent Tachycardia) and PALPITATIONS (heart palpitation) had not resolved and DIZZINESS (lightheadedness), CONDITION AGGRAVATED (Condition aggravated) and CHEST PAIN (chest pain) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 20-Apr-2021, Heart rate: 100 breaths per minute.     The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.       Concomitant product use also included tea containing Ashwaganda Roots, Ginger Roots. The patient visited ER 3 times for intermittent Tachycardia, the first time being on 20 April 2021. The patient was treated with IV fluids for Intermittent Tachycardia. Patient was given a stress test On May 11, 2021. The patient underwent unspecified blood test on 20-APR-2021 and 23-APR-2021 and results were not reported. On 20-APR-2021 and 23-APR-2021, Chest X-ray was done and results were not reported. On 27-APR-2021 and 19-MAY-2021, Echocardiogram was done and the results were not reported. On 20-APR-2021, 23-APR-2021, 26-APR-2021 and 27-APR-2021 Electrocardiogram was done and the results were not reported.  Company comment: This case concerns a 39 year-old  female subject with  medical history of neurophaty and vertigo, who experienced the serious unexpected event of tachycardia and other non serious events. The events occurred 15  days after receiving the first dose of spikevax. At the time of the report the event was not resolved. Rechallenge is negative for this event, since had not resolved at the time patient received the second dose. Patient´s medical history of vertigo and the concomitant use of gabapentin and herbal roots remains as confounders for the event. The benefit-risk relationship of spikevax is not affected by this report.   Most recent FOLLOW-UP information incorporated above includes: On 03-May-2021: Upon internal review on 12-Oct-2021, Suspect product ( Dose 2 ) details were updated from 05-Mar-2021 to 03-May-2021. On 03-May-2021: Upon internal review on 16-SEP-2022 non significant corrections performed to update case received from field On 28-May-2021: Follow-up received on 28/5/21.Follow-up contains treatment information and second dose information. On 01-Jun-2021: Follow-up received on 01/06/2021.Follow-up contains patient demographic details, lab data, vaccine and facility information concomitant medication and additional adverse events.; Sender's Comments: This case concerns a 39 year-old  female subject with  medical history of neurophaty and vertigo, who experienced the serious unexpected event of tachycardia and other non serious events. The events occurred 15  days after receiving the first dose of spikevax. At the time of the report the event was not resolved. Rechallenge is negative for this event, since had not resolved at the time patient received the second dose. Patient´s medical history of vertigo and the concomitant use of gabapentin and herbal roots remains as confounders for the event. The benefit-risk relationship of spikevax is not affected by this report.