Knocked out; Lot of blood on the cotton; Bruise; Stiff; Knot in my arm; Lump; Pretty painful; Arm is sore or Really sore; Now I am knocked out and wants to get up; Bruising; Injection site knot/mass; Nauseous; This spontaneous case was reported by a consumer and describes the occurrence of LOSS OF CONSCIOUSNESS (Knocked out) in a 56-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 091D21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included Cancer (cancer almost two years ago (radiation)) and Radiation therapy. Concurrent medical conditions included Trigeminal neuralgia (no medication for it).    On 26-Jul-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, the patient experienced LOSS OF CONSCIOUSNESS (Knocked out) (seriousness criterion medically significant), HAEMORRHAGE (Lot of blood on the cotton), CONTUSION (Bruise), MUSCULOSKELETAL STIFFNESS (Stiff), NODULE (Knot in my arm), MASS (Lump), PAIN (Pretty painful), PAIN IN EXTREMITY (Arm is sore or Really sore), SOMNOLENCE (Now I am knocked out and wants to get up), INJECTION SITE BRUISING (Bruising), INJECTION SITE INDENTATION (Injection site knot/mass) and NAUSEA (Nauseous). At the time of the report, LOSS OF CONSCIOUSNESS (Knocked out), HAEMORRHAGE (Lot of blood on the cotton), CONTUSION (Bruise), MUSCULOSKELETAL STIFFNESS (Stiff), NODULE (Knot in my arm), MASS (Lump), PAIN (Pretty painful), PAIN IN EXTREMITY (Arm is sore or Really sore), SOMNOLENCE (Now I am knocked out and wants to get up), INJECTION SITE BRUISING (Bruising), INJECTION SITE INDENTATION (Injection site knot/mass) and NAUSEA (Nauseous) outcome was unknown.        The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.       Concomitant medication included: Vitamins. No treatment medication was reported.  Patient had the vaccine first dose on Monday (26Jul2021)and it was not very comfortable. This was pretty painful, she flinched. She could not imagine why and then she stayed in the store and she started getting nauseous. She got a cup of water. Her arm was getting stiff so she went to the grocery (store) and she was trying to keep her arm mobile. She did not want it to lock up on her. She finally took the cotton off and there was a lot of blood on the cotton. Then when she came home she said her arm was sore. There was a lump there so she looked in the mirror and she had a bruise and a knot in her arm. Her cousin (who was a nurse) said she should report that. She went to bed yesterday at 5:30/ 6pm and it was 9:45pm when she woke up she thought it was 3 am in the morning. She was knocked out and she wanted to get up. She was not sure if the vaccine was done properly. It was really sore. She did not feel the same when she had her flu shot last time. Done in right arm.  Company Comment: Although the date of onset was not reported. There is evidence of temporal relationship between the reported events and mRNA-1273, based on the vaccine administered date and date of report, hence, causal association cannot be excluded.; Sender's Comments: Although the date of onset was not reported. There is evidence of temporal relationship between the reported events and mRNA-1273, based on the vaccine administered date and date of report, hence, causal association cannot be excluded.