Left Arm Had A Lump; Left Arm Was Very Itchy; Left Arm Was Red; Mastitis; Deathly Sick; Sleeping All Night; Not Eating Or Drinking A Lot; Very Dizzy; This spontaneous case was reported by a consumer and describes the occurrence of MASTITIS (Mastitis), ILLNESS (Deathly Sick), SOMNOLENCE (Sleeping All Night), DECREASED APPETITE (Not Eating Or Drinking A Lot) and DIZZINESS (Very Dizzy) in an 81-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 017C21A and 039C21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included Mastitis (breast infections infection flared up 4-jun-2021). Concurrent medical conditions included Lipoma and Hypertension. Concomitant products included AMOXICILLIN, CLAVULANIC ACID (AMOXCLAV [AMOXICILLIN;CLAVULANIC ACID]), FISH OIL, PARACETAMOL (TYLENOL), AMLODIPINE, ROSUVASTATIN CALCIUM (CRESTOR), VALSARTAN (DIOVAN), HYDROCHLOROTHIAZIDE, METFORMIN and TRIAMCINOLONE for an unknown indication.   On 28-May-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 29-Jun-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 04-Jun-2021, the patient experienced MASTITIS (Mastitis), ILLNESS (Deathly Sick), SOMNOLENCE (Sleeping All Night), DECREASED APPETITE (Not Eating Or Drinking A Lot) and DIZZINESS (Very Dizzy). On 09-Jun-2021, the patient experienced VACCINATION SITE MASS (Left Arm Had A Lump), VACCINATION SITE PRURITUS (Left Arm Was Very Itchy) and VACCINATION SITE ERYTHEMA (Left Arm Was Red). On 08-Jun-2021, ILLNESS (Deathly Sick), SOMNOLENCE (Sleeping All Night), DECREASED APPETITE (Not Eating Or Drinking A Lot) and DIZZINESS (Very Dizzy) had resolved. At the time of the report, MASTITIS (Mastitis) was resolving and VACCINATION SITE MASS (Left Arm Had A Lump), VACCINATION SITE PRURITUS (Left Arm Was Very Itchy) and VACCINATION SITE ERYTHEMA (Left Arm Was Red) outcome was unknown.            Concomitant products included Blood pressure medications and water pill.  On an unknown date, patient was treated with Antibiotic for Mastitis at an unspecified dose and frequency.  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. Patient's history of Mastitis prior to vaccination may be a confounding factor to the event mastitis.   This case was linked to MOD-2021-254125 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 30-Jun-2021: Follow-up received on 30-JUN-2021 contains NNI On 12-Jul-2021: Followed up received on 12-JUL-2021 that contains significant information that includes concomitant medication Amlodipine 10 mg, Crestor 5 mg, Diovan, Hydrochlorothiazide 25 mg, Metformin 500 mg, Triamcinolone 0.025%; 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. Patient's history of Mastitis prior to vaccination may be a confounding factor to the event mastitis.