Itchiness around the neck after 2nd dose/Itchy high on her neck in hairline after 2nd dose; Arm started to hurt really bad after 2nd dose; Arm was very warm below the injection site after 2nd dose/Arm was so hot for a while after 2nd dose; Arm was quite pink after 2nd dose; Rash starting around neck after 2nd dose/Rash from neck down into back after 2nd dose; knocked her out; This spontaneous case was reported by a consumer and describes the occurrence of PRURITUS (Itchiness around the neck after 2nd dose/Itchy high on her neck in hairline after 2nd dose), VACCINATION SITE PAIN (Arm started to hurt really bad after 2nd dose), VACCINATION SITE WARMTH (Arm was very warm below the injection site after 2nd dose/Arm was so hot for a while after 2nd dose), VACCINATION SITE ERYTHEMA (Arm was quite pink after 2nd dose) and RASH (Rash starting around neck after 2nd dose/Rash from neck down into back after 2nd dose) in an 83-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 021c21a and 008ca1a) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No medical history was provided by reporter.  Previously administered products included for Flu: Flu shot (after a flu shot over 20 years ago she woke up with a rash all over her body. She says she hasn't taken a flu shot since that time.). Past adverse reactions to the above products included Rash all over with Flu shot.   On 04-May-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 01-Jun-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient experienced PRURITUS (Itchiness around the neck after 2nd dose/Itchy high on her neck in hairline after 2nd dose), VACCINATION SITE PAIN (Arm started to hurt really bad after 2nd dose), VACCINATION SITE WARMTH (Arm was very warm below the injection site after 2nd dose/Arm was so hot for a while after 2nd dose), VACCINATION SITE ERYTHEMA (Arm was quite pink after 2nd dose), RASH (Rash starting around neck after 2nd dose/Rash from neck down into back after 2nd dose) and SOMNOLENCE (knocked her out). The patient was treated with DIPHENHYDRAMINE HYDROCHLORIDE (BENADRYL [DIPHENHYDRAMINE HYDROCHLORIDE]) for Adverse event, at a dose of 1 dosage form. At the time of the report, PRURITUS (Itchiness around the neck after 2nd dose/Itchy high on her neck in hairline after 2nd dose), VACCINATION SITE PAIN (Arm started to hurt really bad after 2nd dose), VACCINATION SITE WARMTH (Arm was very warm below the injection site after 2nd dose/Arm was so hot for a while after 2nd dose), VACCINATION SITE ERYTHEMA (Arm was quite pink after 2nd dose), RASH (Rash starting around neck after 2nd dose/Rash from neck down into back after 2nd dose) and SOMNOLENCE (knocked her out) outcome was unknown.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   No concomitant medications were provided by reporter.  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.  For the event somnolence the drug diphenhydramine is a co suspect.   Most recent FOLLOW-UP information incorporated above includes: On 02-Aug-2021: Follow-up received on 02-AUG-2021 contains No new information.; 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.  For the event somnolence the drug diphenhydramine is a co suspect.