Received Oct 30, 2025
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| COVID19 | COVID19 (COVID19 (MODERNA)) | MODERNA | UNK | — | IM |
I was sick for a while; brain fog/ brain fogging; I just haven't been the same/felt different after receiving the vaccine/something's been different with me in the last few years; This spontaneous case was reported by a consumer and describes the occurrence of ILLNESS (I was sick for a while), BRAIN FOG (brain fog/ brain fogging) and IMMUNISATION REACTION (I just haven't been the same/felt different after receiving the vaccine/something's been different with me in the last few years) in a 68-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis. Previously administered products included for Product used for unknown indication: COVID-19 VACCINE (Patient had the vaccines from several different places at the time.). Past adverse reactions to the above products included No adverse effect with COVID-19 VACCINE. In 2021, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular use) 1 dosage form. On an unknown date, the patient experienced ILLNESS (I was sick for a while), BRAIN FOG (brain fog/ brain fogging) and IMMUNISATION REACTION (I just haven't been the same/felt different after receiving the vaccine/something's been different with me in the last few years). At the time of the report, ILLNESS (I was sick for a while), BRAIN FOG (brain fog/ brain fogging) and IMMUNISATION REACTION (I just haven't been the same/felt different after receiving the vaccine/something's been different with me in the last few years) outcome was unknown. Concomitant medication was not provided. It was reported that the patient was a poor narrator and asked whether brain fog was one of the side effects of the SPIKEVAX. She explained that she had felt different after receiving the vaccine. She mentioned that she was unsure whether she had contracted COVID-19 but had been sick for a while. She stated that after taking the vaccine, she hadn't felt the same and wanted to know if brain fog could be a side effect, as she had heard such claims. She believed the vaccine she received was administered in 2021 but wasn't certain and said she would need to confirm with her daughter. She expressed concern that something had changed in her over the past few years and noted that others had observed this as well. She further added that the connection was poor and she couldn't hear well on her end. She recalled receiving vaccines from several different locations where she had gone with her daughter. She admitted that her daughter would have better knowledge of the details, as she herself didn't remember them clearly. It was unknown if the patient experienced any additional symptoms or events. Treatment medication was not reported. Most recent FOLLOW-UP information incorporated above includes: On 20-Oct-2025: Live follow-up received and significant information includes added reporter phone number, added medical history, new event brain fog added, updated suspect drug and updated narrative On 23-Oct-2025: Upon internal review on 24-Oct-2025, it was identified that the case MOD-2025-790537 (US-MODERNATX-MOC20251024000012) was created inadvertently as an initial case instead of adding follow up to the already existing case MOD-2025-790427 (US-MODERNATX-MOC20251021000013). Hence, all the information from the case MOD-2025-790537 (US-MODERNATX-MOC20251024000012) has been added and merged into the retained case MOD-2025-790427 (US-MODERNATX-MOC20251021000013) as a follow-up. The case MOD-2025-790537 (US-MODERNATX-MOC20251024000012) will be deleted from the safety database. Live Follow-up received contains no new information. On 23-Oct-2025: Live follow-up received and non-significant information includes reference ids added.