GUILLIAN BARRE; This spontaneous report was received from a consumer (the patient's wife) and concerned a 42 year old male. The patient's weight was 170 pounds and his height was 76 inches. The patient was a non-smoker, a non-drinker, had no known allergies and no prior or underlying medical history or past medications. The patient received COVID-19 vaccine Ad26.CoV2.S (suspension for injection, route of admin not reported, batch number reported as unknown), dose not reported administered once in total to the left arm on 12-MAY-2021 for prophylactic vaccination. The batch number was not reported and has been requested. No concomitant medications were reported.  On 12-MAY-2021 (same day post-vaccination), the patient felt tired, but felt better on the second day (13-MAY-2021). On 14-MAY-2021, two days post vaccination, the patient went to work (works as a landscaper) where he fell over and twisted his ankle. This happened again later during the day and after a few days, he felt that his feet were not picking up (like Frankenstein syndrome). Patient could not move his toes and his feet felt sloppy like a drop foot. After 2 weeks, on 26-MAY-2021, the patient started experiencing tingling and numbness in his arms and had to wake up in the middle of the night to shake his arm. The patient's physician referred him to a neurologist, the neurologist thought that it could be a case of transverse myelitis and asked him to go to the emergency room (ER) immediately. At the ER, all his tests were run such as x-rays, magnetic resonance imaging (MRI), coronavirus disease (COVID-19) test, together with unspecified blood work and neurological tests, the results of which were not provided. The patient was diagnosed with Guillain-Barre syndrome and was hospitalized on 04-JUN-2021 where he was being treated with immunoglobulins (product unspecified) and was discharged on 08-JUN-2021 (duration of hospitalization: 5 days). On 17-JUN-2021 in the morning, patient fell in his garage. At the time of reporting, patient couldn't lift his toes. Patient was perfectly healthy prior to the shot. Patient was getting mentally affected as everything felt like labor and work seemed burdensome. At the time of the report, all his symptoms were ongoing. The action taken with COVID-19 vaccine Ad26.CoV2.S was not applicable. The patient had not recovered from Guillain-Barre syndrome. This report was serious (caused/prolonged hospitalization). This case, from the same reporter is linked to 20210637283.; Sender's Comments: V0: This spontaneous report received from the patient's wife concerns a 42-year-old male who was hospitalized for Guillain-Barre syndrome (GBS) 23 days after receiving Janssen Covid-19 vaccine. He does not smoke or drink alcohol, does not have underlying medical conditions, and was not taking concomitant medications. Two days post vaccination, he fell and injured his ankle twice while at work as a landscaper. After a few more days, he felt difficulty lifting his feet and could not move his toes. Fourteen days post-vaccination, tingling and numbness began in his arms, and he was referred to a neurologist who then referred him to the emergency room (ER) out of concern for possible transverse myelitis. At the ER, x-rays, MRI, Covid-19 tests, and other unspecified blood & neurologic tests were performed; results not reported. Twenty-three days post-vaccination, he was diagnosed with GBS and hospitalized. He was treated with immunoglobulins and was discharged 4 days later. Nine days after discharge, the patient fell in his garage and could not lift his toes. At the time of this report, the patient had not recovered. Information regarding potential etiologies of GBS is insufficient, and the occurrence of the events could represent background incidence of such events in the general population. Considering the temporal relationship, the events are assessed to have an indeterminate relationship with vaccination.