This spontaneous case was reported by a consumer and describes the occurrence of ANAPHYLACTIC REACTION (anaphylaxis) and HEADACHE (headache/breakthrough headaches) in a 25-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 030L20A and 025J20A) for COVID-19 vaccination. Concomitant products included BUSPIRONE HYDROCHLORIDE (BUSPAR) and SERTRALINE HYDROCHLORIDE (ZOLOFT) for an unknown indication. On 30-Dec-2020, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 27-Jan-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 12-Nov-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 14-Nov-2021, the patient experienced ANAPHYLACTIC REACTION (anaphylaxis) (seriousness criteria hospitalization and medically significant) and HEADACHE (headache/breakthrough headaches) (seriousness criterion hospitalization). The patient was hospitalized on 15-Nov-2021 due to ANAPHYLACTIC REACTION and HEADACHE. The patient was treated with EPINEPHRINE from November 2021 to November 2021 for Anaphylactic reaction, at a dose of UNKNOWN; PREDNISONE on 12-Jan-2022 for Adverse event, at a dose of 40 milligram; PREDNISONE for Adverse event, at a dose of 30 milligram; PREDNISONE for Adverse event, at a dose of 20 milligram; PREDNISONE for Adverse event, at a dose of 10 milligram; PREDNISONE in November 2021 for Adverse event, at an unspecified dose and frequency; METOPROLOL SUCCINATE (TOPROL XL) ongoing from 22-Nov-2021 for Tachycardia, at a dose of 50 milligram once a day; ALBUTEROL [SALBUTAMOL] ongoing since an unknown date for Adverse event, at an unspecified dose and frequency; ALBUTEROL [SALBUTAMOL] ongoing since an unknown date for Adverse event, at an unspecified dose and frequency; MONTELUKAST SODIUM (SINGULAIR) ongoing since an unknown date for Adverse event, at a dose of 10 milligram once a day; CETIRIZINE HYDROCHLORIDE (ZYRTEC [CETIRIZINE HYDROCHLORIDE]) in November 2021 for Adverse event, at a dose of 10 milligram four times per day; FAMOTIDINE (PEPCID [FAMOTIDINE]) for Inflammation, at a dose of 20 milligram twice a day; UBROGEPANT (UBRELVY) for Headache, at a dose of 50 milligram; ESZOPICLONE (LUNESTA) for Adverse event, at a dose of 2 milligram once a day; TRAZODONE for Adverse event, at a dose of 50 milligram once a day; CLARITHROMYCIN (CLARITIN [CLARITHROMYCIN]) for Adverse event, at a dose of 10 milligram once a day; DIPHENHYDRAMINE HYDROCHLORIDE (BENADRYL [DIPHENHYDRAMINE HYDROCHLORIDE]) for Adverse event, at a dose of 50 milligram once a day; FLUTICASONE FUROATE, UMECLIDINIUM BROMIDE, VILANTEROL TRIFENATATE (TRELEGY) for Adverse event, at a dose of 1 dosage form once a day; OXYGEN from November 2021 to November 2021 for Anaphylactic reaction, at an unspecified dose and frequency; FUROSEMIDE (LASIX [FUROSEMIDE]) for Fluid retention, at a dose of 20 milligram once a day and ATOGEPANT for Headache, at a dose of 1 dosage form once a day. At the time of the report, ANAPHYLACTIC REACTION (anaphylaxis) had not resolved and HEADACHE (headache/breakthrough headaches) outcome was unknown. For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments. The patient's symptoms started on 14-Nov-2021, but they didn't get worse until 15-Nov-2021. She went into anaphylaxis and was hospitalized for 5 nights and 6 days starting 15-Nov-2021. She hasn't been better unfortunately. She had been on steroids since 15Nov2021. She was tachycardia and on beta blockers to keep her from anaphylaxis and breathing ok. Her hives started on 14-Nov-2021. Her face started swelling, and her airwaves started to swell. It got worse from there. The patient had received epinephrine twice in the hospital. She was on oxygen for about 4 days. She was up 20 pounds since the symptoms started. She could drop 15-20 pounds in a day because she was retaining fluid. If she stopped taking Zyrtec, her hands got red, bumpy, and itchy again. Her tongue would get small little bumps too. She also had headache and breakthrough headaches. If the dose of prednisone had been decreased to 10 mg, she started getting wheezy and her O2 (oxygen) saturation dropped. Treatment medicine includes steroids since 15-Nov-2021 and prednisone as taper dose and EpiPen but patient didn't take it. Company comment include: This case concerns a 25-year-old female patient with no medical history provided, who experienced serious expected event of Anaphylactic reaction and serious unexpected event of Headache. The events occurred two days after the patient had received the third dose of the mRNA-1273 vaccine. The patient developed urticaria, swelling of the face and respiratory tract. However, as the symptoms worsened during the next day, the patient went to hospital and was hospitalized due to anaphylaxis. The patient was hospitalized for 6 days. The treatment medications included steroids, beta blockers, epinephrine, cetirizine, prednisone and oxygen therapy. The patient also gained 20 pounds since the symptoms started, due to fluid retention and was treated with Lasix. It was stated that the patient also had headache and breakthrough headaches, which was treated with Qulipta and Ubrelvy. In addition, the patient also started to take the following medications as treatment: Albuterol (inhaler and nebulizer), Singulair, Pepcid, Lunesta, Trazodone, Claritin, Benadryl and Trelegy. At the time of this report, the event of Anaphylactic reaction had not resolved, while the outcome of the event of Headache remained unknown. The re-challenge is not applicable as the events occurred following the third dose of the vaccine. The benefit-risk relationship of the mRNA-1273 vaccine is not affected by this report. Sender's Comments: This case concerns a 25-year-old female patient with no medical history provided, who experienced serious expected event of Anaphylactic reaction and serious unexpected event of Headache. The events occurred two days after the patient had received the third dose of the mRNA-1273 vaccine. The patient developed urticaria, swelling of the face and respiratory tract. However, as the symptoms worsened during the next day, the patient went to hospital and was hospitalized due to anaphylaxis. The patient was hospitalized for 6 days. The treatment medications included steroids, beta blockers, epinephrine, cetirizine, prednisone and oxygen therapy. The patient also gained 20 pounds since the symptoms started, due to fluid retention and was treated with Lasix. It was stated that the patient also had headache and breakthrough headaches, which was treated with Qulipta and Ubrelvy. In addition, the patient also started to take the following medications as treatment: Albuterol (inhaler and nebulizer), Singulair, Pepcid, Lunesta, Trazodone, Claritin, Benadryl and Trelegy. At the time of this report, the event of Anaphylactic reaction had not resolved, while the outcome of the event of Headache remained unknown. The re-challenge is not applicable as the events occurred following the third dose of the vaccine. The benefit-risk relationship of the mRNA-1273 vaccine is not affected by this report.