Abdomen hurts every time I eat something I just have pain in stomach; every time I eat something it just goes right through me, my stomach starts hurting and I go to the bathroom, peeing out of bed; Diarrhea; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient.  A 58-year-old male patient received BNT162b2, BNT162b2 omi ba.4-5 (BNT162B2, BNT162B2 OMI BA.4-5), on 06Jun2023 as dose 3 (booster), single (Batch/Lot number: unknown) at the age of 58 years, in left arm for covid-19 immunisation. The patient's relevant medical history included: "I have heart disorder already" (ongoing); "blood pressure" (unspecified if ongoing); "cholesterol" (unspecified if ongoing); "swelling on my leg" (unspecified if ongoing); "I don't get dehydrated" (unspecified if ongoing). Concomitant medication(s) included: ASPIRIN (E.C.) taken for peripheral swelling; CALCIUM taken for dehydration; MINERAL taken for dehydration. Vaccination history included: Bnt162b2 (DOSE 1, SINGLE), for Covid-19 immunization; Bnt162b2 (DOSE 2, SINGLE), for Covid-19 immunization. The following information was reported: DIARRHOEA (non-serious) with onset 07Jun2023, outcome "not recovered", described as "Diarrhea"; ABDOMINAL PAIN UPPER (non-serious), outcome "not recovered", described as "Abdomen hurts every time I eat something I just have pain in stomach; every time I eat something it just goes right through me, my stomach starts hurting and I go to the bathroom, peeing out of bed". Relevant laboratory tests and procedures are available in the appropriate section. Therapeutic measures were taken as a result of diarrhoea, abdominal pain upper.  Additional Information: Consumer stated, "I just have some medical issues that I wish, I want to know, I didn't know this was a trial drug that I was just given, went to get the booster of Pfizer (Clarified as Pfizer COVID 19 Booster) because that is what I had in the first two shots and I had no problem but ever since I had the shot the very right next day I have had diarrhea for about a week and a half now it won't go away. My abdomen hurts every time I eat something I just have pain in my stomach. I have heart disorder already so it is kind of making me nervous because of all those, what is happening is, it seems like its not getting better. I do not know what to do, should I go to the hospital? Why did not they tell me this was a trial thing before they gave me the shot. They gave me this paper after they gave me the shot, and sent me home and I was reading it and it is like a trial basis. I wish I would have know I would have not taken it or haven't given to me because I already have a heart condition." When paraphrased the concern: Consumer stated, "I have been experiencing every day since I had it done on Monday, Tuesday of last week and I still have it, every time I eat something it just goes right through me, my stomach starts hurting and I go to the bathroom, peeing out of my bed. I was already down for a week. I have taken stuff like Tums and stuff (Unspecified medication) but it's not helping." Consumer stated, "They just give a shot in the shoulder. Mine was left because I am right handed so she put it in my left." Date and time: Consumer stated, "It was in the morning 06Jun2023 and it was 9 or 10 in the morning. More likely nine so that was earlier I was like the only one in there " Lab work: Consumer stated, "Yes I had actually, it was before I got the shot, they give me an EMG for my legs. EMG I do not know it is electro, to measure muscle growth and stuff." Other medical condition and concomitant medication: Consumer stated, "I am taking other medicine but it is just routine medicine, one for blood pressure, one for cholesterol. I take Aspirin and Lesparol for swelling on my leg. I take calcium pill, minerals so I don't get dehydrated." Treatment for Diarrhea: Consumer stated, "I was trying to take Alka Seltzer I had it and then I took Tums and I took Imodium."   The information on the batch/lot number for BNT162b2, BNT162b2 omi ba.4-5 has been requested and will be submitted if and when received.; Sender's Comments: Linked Report(s) : US-PFIZER INC-202300222265 same patient/drug, different dose/event;US-PFIZER INC-202300222264 same patient/drug, different dose/event;