LOSS OF CONSCIOUSNESS, FAINTED; HEART WAS RACING; DIZZY; VOMITING; CANKER SORE UNDER TONGUE; HEADACHE; NAUSEA; FATIGUE; INFLAMMATION ON LEFT EYE; FALL ON BED; SMALL HIVES UNDER EYE; This spontaneous report received from a patient concerned a 63 year old female. The patient's weight, height, and medical history were not reported.  The patient's concurrent conditions included seasonal allergies, and codeine allergy. The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 1802068, expiry: UNKNOWN) dose was not reported, administered on 05-MAR-2021 to left arm as prophylactic vaccination. No concomitant medications were reported.  On 06-MAR-2021, after vaccination, she felt fine all day and night. The next morning she woke up and felt sick. She had nausea, headache, hive under eye. She laid back down and tried to sleep. A few hours later, she woke up to use the bathroom. She was very nauseous and dizzy. She lost consciousness and fell trying to get to the bathroom. She fell on her bed and was uninjured. The paramedics took her to the hospital. She was given medication for nausea, headache, and IV fluids. She gave blood for lab tests and they came back normal. No COVID test was administered. When she felt better, she was released. A few days later, she discovered her tongue was sore and red. She called her primary care physician (PCP). PCP said the red and sore tongue was probably related to allergies. Two weeks later, her tongue was not sore, but still red. They advised her to get a second opinion with another HCP. She was going to visit her allergy specialist.. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from loss of consciousness, fainted, heart was racing, dizzy, headache, nausea, fatigue, inflammation on left eye, and small hives under eye on MAR-2021, and vomiting on 07-MAR-2021, and had not recovered from canker sore under tongue, and the outcome of fall on bed was not reported. This report was serious (Hospitalization Caused / Prolonged).  Additional information was received from the patient on 23-Mar-2021. The following information was updated and incorporated into case narrative: Patient's medical history added as seasonal allergies and codeine allergy, Vaccination site as left arm added; Additional events as small hives under eye, fall on bed; lab test of blood work added; Event outcome of loss of consciousness, fainted, heart was racing, dizzy, headache, nausea, and fatigue was updated to recovered/resolved.; Sender's Comments: v1: Follow up information received updates  patient's medical history (seasonal allergies and codeine allergy), Vaccination site as left arm; Additional events (small hives under eye and fall on bed), laboratory test (Blood Work); Event outcome  (loss of consciousness, fainted, heart was racing, dizzy, headache, nausea and fatigue was updated to recovered/resolved). This updated information does not alter prior causality assessment of reported events 20210323730-COVID-19 VACCINE AD26.COV2.S-headache, nausea and fatigue. These events are labeled and are therefore considered potentially related. 20210323730-COVID-19 VACCINE AD26.COV2.S-loss of consciousness, fainted, heart racing, dizzy, vomiting, canker sore under tongue. These events are considered unassessable. The events have a compatible/suggestive temporal relationship, are unlabeled, and have unknown scientific plausibility. There are no information on any other factors potentially associated with the events.