my platelets have fallen to down to about 46; now down to a 38; I had too much of headache; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient.  A 67-year-old male patient received BNT162b2 (BNT162B2), in Jan2022 as dose 3 (booster), single (Lot number: FJ1611) at the age of 67 years for covid-19 immunisation. The patient's relevant medical history included: "COVID-19", start date: Jan2021 (unspecified if ongoing), notes: My wife and I both got COVID-19 in Jan2021, immediately got the Regeneron treatment; "biopsy" (unspecified if ongoing), notes: On 23Dec, I also had a biopsy out of my left hip; "hearing disability" (unspecified if ongoing); "blood pressure" (unspecified if ongoing), notes: I am on a blood pressure medication, Losartan. Tamsulosin for prostrate; "prostrate" (unspecified if ongoing), notes: I am on a blood pressure medication, Losartan. Tamsulosin for prostrate. Concomitant medication(s) included: TAMSULOSIN taken for prostate cancer; LOSARTAN taken for blood pressure abnormal. Vaccination history included: Bnt162b2 (Primary immunization series complete., I do have my original Pfizer vaccine dates, both of them), for COVID-19 immunization. The following information was reported: HEADACHE (non-serious) with onset Jan2022, outcome "unknown", described as "I had too much of headache"; PLATELET COUNT DECREASED (medically significant) with onset Jan2022, outcome "unknown", described as "my platelets have fallen to down to about 46; now down to a 38". The patient underwent the following laboratory tests and procedures: Blood test: (03Jan2023) unknown results; Platelet count: (unspecified date) below 50; (Feb2022) 38, notes: He called me at 09:30 the next morning and said this is no mistake. You are now down to a 38; (Feb2022) 46, notes: During my Feb checkup, everything was just fine just like it was in Aug except my platelets have fallen to down to about 46; (03Jan2023) My platelets were down to 1 again today. Therapeutic measures were taken as a result of platelet count decreased, headache.  Clinical course: It was reported, the patient received a booster back in Jan2022 and previously had a checkup in Aug2021. Then had another checkup in Feb2022. Now had too much of headache between those 2 appointments and he was just not a sick person. He got the booster in Jan, about the second week of 2022. During Feb checkup, everything was just fine just like it was in Aug except platelets have fallen to down to about 46. Informed Doctor this could be a mistake, while he was there just drew some more blood. So they did. At 09:30 the next morning there was no mistake. He was now down to a 38. Doctor needed him to see an oncologist ASAP and its miserable ever since. He wound up seeing another oncologist. For about the first 4 weeks after discovering this, in Feb he was on Rituxan treatment. He had a hearing disability (Intent: medical history) and he didn't do well. So if he didn't get it, that's why. So after the 4 Rituxan treatments, he then was put on an IVIg. Had about 4 of those. They put him on Prednisone, a high dose, of about a 140mg. He was on that for 3 months. That did not work. That is an oral medication and that did now work. What we are trying to do here is give this to you in chronological order. So in Jun, he started an oral medication. He started the Nplate shots. That definitely boostered his platelets but sometimes, when started in the Nplate in Jun, he got down as low as 1 and he should have been between 150 and 400. So then started the Nplate regimen. Did it every week for a while and then every 2 weeks and then about the time started on every 2 weeks, tried an oral medication called Promacta, tried that for about 4 weeks and it didn't do anything. So went back on the Nplate shot again and anyway, it would bring up, the Nplate shot would bring up his platelets but then his body would destroy them within two weeks. He would be down below 40 and 50. He was also, back when this first started Feb Mar, on the Rituxan he was having very difficulty getting IV started and platelets were below 50. So they wind up pricking (Not clarified over the call) in arm and then once got the platelets built up, when the Nplate started, that is approximately when he got the 'portal' (Not clarified over the call) in chest. The first part of Jul, went from the pricking to a port in chest (Not clarified over the call), on right side of chest. So stayed on the Nplate shots up to, in Aug tried the oral medication. He had to go back to Nplate and 21Dec, tried another oral medicine called Tavalisse, had blood work done and that medicine also was not working. Just disappointment coming in 2023. Platelets were down to 1 again. They had been hoping could find something, his wife and he were both retired. He was 68 years old. They were taking him off the oral medication Tavalisse and putting on 4 days of steroids and also got the Nshots started again. On 23Dec, he also had a biopsy out of left hip (Not clarified over the call). That seemed to be okay, don't have a final result still, will get back to the oncologist again. He and his wife both got COVID-19 in Jan2021, immediately got the Regeneron treatment and then we were both vaccinated in about June or July. Then in Jan, about the second week of 2022, that is when he got that booster and that is when things just went. It was after he got the booster. He was fine after he got that booster and got a reference to back that up. Other treatment in response to adverse event was Tylenol and Celebrex. He was on a blood pressure medication, Losartan. Tamsulosin for prostrate.