fatigue; they have experienced brain fog; he experienced splitting headache; Adverse Effect/obscure reaction; This spontaneous case was reported by a consumer and describes the occurrence of FATIGUE, FEELING ABNORMAL, HEADACHE, and VACCINATION COMPLICATION in a 22-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 025C21A and 041B21A) for COVID-19 vaccination.     No Medical History information was reported.   On 13-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 11-May-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date, the patient experienced FATIGUE (seriousness criterion hospitalization), FEELING ABNORMAL (seriousness criterion hospitalization), HEADACHE (seriousness criterion hospitalization), and VACCINATION COMPLICATION (seriousness criterion hospitalization). The patient was hospitalized from 09-Sep-2021 to sometime in September 2021 due to FATIGUE, FEELING ABNORMAL, HEADACHE, and VACCINATION COMPLICATION. The patient was treated with TYLENOL for Adverse event, at an unspecified dose and frequency; REGLAN for Adverse event, at an unspecified dose and frequency; MAGNESIUM for Adverse event, at an unspecified dose and frequency; AJOVY for Adverse event, at an unspecified dose and frequency; FIORICET for Adverse event, at an unspecified dose and frequency; NARATRIPTAN for Adverse event, at an unspecified dose and frequency; ZONISAMIDE for Adverse event, at an unspecified dose and frequency; NURTEC for Adverse event, at an unspecified dose and frequency and AMOXICILLIN for Adverse event, at a dose of 15 day course. At the time of the report, FATIGUE, FEELING ABNORMAL, HEADACHE, and VACCINATION COMPLICATION had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood test Normal. On an unknown date, Electroencephalogram Normal. On an unknown date, Lumbar puncture Normal. On an unknown date, Magnetic resonance imaging Normal. On an unknown date, Sleep study Normal.         No concomitant medications were reported.  In treatment details, two steroid packs was also prescribed by the HCP's.  Patient reported that he had been experiencing splitting headaches since five months.  Patient reported that he was fine after first dose.  Patient reported that he had been to a ton of doctors including 3 neurologists, 1 PCP, and 1 ENT.  He had been to emergency room three times.  His first visit to ER was in the month of August as his symptoms got progressively worse. On 09-Sep-2021, patient visited ER for the third time and the stay was for 36 hours.  Patient's neurologist think that they are not migraines, in there opinion they are obscure reaction to second dose.  This case concerns a 22-year-old, male with unknown medical history, who experienced the unexpected serious (hospitalization criteria) events of headache, fatigue, feeling abnormal and vaccine adverse reaction. The event occurred after the second dose of mRNA-1273 Moderna vaccine (Spikevax) with no exact latency known. The rechallenge was not applicable since this events happened after the second dose and no further dose is expected. The benefit-risk relationship of mRNA-1273 Moderna vaccine in not affected by this report.