Guillain-Barré syndrome; orthostatic light headedness; Difficulty in walking; didnot feel great; Itching; short term memory; chest tightness; Brain fog; Numbness; Tingling; Pain; swelling of hands; joint pain; fatigue; swelling at injection site; Injection site pain; headache; Nausea; rash; Chills; This spontaneous case was reported by a consumer and describes the occurrence of GUILLAIN-BARRE SYNDROME (Guillain-Barré syndrome) in a 41-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 030L20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No medical history information was provided by the reporter.  Concurrent medical conditions included Fruit allergy (Strawberries :Anaphylaxis + Angioedema), Seafood allergy (Shrimp) since 2012, Allergy to nuts (Walnuts[unsure]:Oral itching and jaw tightening.), Food allergy (Mushrooms[ nausea and vomiting]) since 1995, Anaphylaxis since 2012, Hay fever, Urticaria, Migraine, Diverticulosis since 2017, Connective tissue disorder NOS (Suspected), Eczema and Allergic rhinitis. Concomitant products included PLANTAGO OVATA (METAMUCIL [PLANTAGO OVATA]) for Diverticulosis, SUMATRIPTAN for Migraine, TRAMADOL for Pain, CETIRIZINE HYDROCHLORIDE (CETRIZINE) for an unknown indication.    On 28-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On an unknown date, the patient experienced DIZZINESS POSTURAL (orthostatic light headedness), GAIT DISTURBANCE (Difficulty in walking), GUILLAIN-BARRE SYNDROME (Guillain-Barré syndrome) (seriousness criterion medically significant), FEELING ABNORMAL (didnot feel great), PRURITUS (Itching), AMNESIA (short term memory), CHEST DISCOMFORT (chest tightness), FEELING ABNORMAL (Brain fog), HYPOAESTHESIA (Numbness), PARAESTHESIA (Tingling), ARTHRALGIA (joint pain), FATIGUE (fatigue), VACCINATION SITE SWELLING (swelling at injection site), VACCINATION SITE PAIN (Injection site pain), HEADACHE (headache), NAUSEA (Nausea) and RASH (rash). At the time of the report, DIZZINESS POSTURAL (orthostatic light headedness), GAIT DISTURBANCE (Difficulty in walking), GUILLAIN-BARRE SYNDROME (Guillain-Barré syndrome), FEELING ABNORMAL (didnot feel great), PRURITUS (Itching), AMNESIA (short term memory), CHEST DISCOMFORT (chest tightness), FEELING ABNORMAL (Brain fog), PARAESTHESIA (Tingling), ARTHRALGIA (joint pain), FATIGUE (fatigue), VACCINATION SITE SWELLING (swelling at injection site), VACCINATION SITE PAIN (Injection site pain), HEADACHE (headache), NAUSEA (Nausea) and RASH (rash) outcome was unknown and HYPOAESTHESIA (Numbness) had not resolved.        The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) was unknown.       Lab test include: Cardiovascular evaluation include tilt table test, Rheum workup, Ultrasound were known to cause Rheum.  No treatment information was provided.   This case was linked to MOD-2021-058060 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 11-May-2021: Follow-up Information received contains No New Information. On 14-Jul-2021: Updated Reporter address. Updated Patient demographics[Height, Weight, Race, Ethinicity ] .Added medical history include  Allergies, current medical conditions. Added concomitant medications. Added Vaccine facility information. Added new Events.; 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.