HYPOTHERMIA; LOSS OF TASTE; ARM WAS LIKE ROCK SOLID; RASH ON LEFT ARM AND WENT ALL OVER THE BODY; HURTING ARM; WEAKNESS; FEVER; FLUCTUATING BLOOD GLUCOSE LEVEL; LIGHT HEADED; DIARRHEA; This spontaneous report received from a patient concerned a 45 year old male. The patient's height, and weight were not reported. The patient's past medical history included sinus surgery, and spine surgery, and concurrent conditions included type 2 diabetes mellitus, allergy to pecan walnut, allergic to pollen, allergic to lobster/oyster, allergic to molds, allergic to dust, and allergic to cat hair. The patient experienced drug allergy when treated with doxycycline.  The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 041A21A, expiry: UNKNOWN) dose was not reported, 1 total administered on 05-APR-2021 16:00 to left arm for prophylactic vaccination. No concomitant medications were reported.  On 05-APR-2021, within 1-2 hours after getting vaccinated the patient experienced a rash on left arm where he got the vaccine and it went all over the body. On the same day, his temperature was 95.1 F On 05-APR-2021, he also experienced weakness that lasted for a week. His arm was hurting and was like rock solid for almost ten days. The patient was feeling light headed that started on the same day of vaccination and could be due to low glucose level. The patient had diarrhea that started the same day as vaccination and was still ongoing. The patient's blood glucose was going up and down since the vaccination. On 05-APR-2021 at 23:05, his blood glucose level was 249 mg/dl. On 05-APR-2021 around midnight the patient had a fever of 101.9F. The patient experienced fever for first three days after vaccination, for which he took Tylenol for three days as directed by his physician. The patient took Tylenol 500 mg for every four hours total he took 5 pills on day one. The next day he took 3 pills of Tylenol 500 mg. On 06-APR-2021 at 8:00, his blood glucose level was 349 mg/dl and then he took his medication and it went down to 169 mg/dl. The patient stated that since vaccination his blood glucose has been unstable and the blood glucose readings are between 47 to 389 mg/dl. On 06-APR-2021, his temperature reading was 94.3 F. The patient also experienced loss of taste on the day after vaccination which has resolved now. His taste came back about a week or 10 days. The patient was not sure if the loss of taste is due to his allergy or the vaccine. On 07-APR-2021, the patient's temperature was 99.7 F. On 07-APR-2021, he took 500 mg every 6 hours. The patient took Tylenol for only three days and fever stopped after three days. On 07-APR-2021 the patient experienced hypothermia of 94.3 F. On 18-APR-2021 at 6:30, his glucose level was 95 mg/dl. The patient said that he had such unstable blood glucose readings only when he had an infection going on. On Friday the patient was going to see his endocrinologist. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from hypothermia, loss of taste, arm was like rock solid, hurting arm, and weakness on APR-2021, and fever on 07-APR-2021, had not recovered from diarrhea, and fluctuating blood glucose level, and the outcome of rash on left arm and went all over the body and light headed was not reported. This report was serious (Other Medically Important Condition).; Sender's Comments: V0 20210438172- COVID-19 VACCINE AD26.COV2.S- Hypothermia, Fluctuating blood glucose level. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: MEDICAL HISTORY.