passed out for a very short period of  time; was awakened by total body shaking and it was not just shivers but was uncontrollable shaking; her body felt warm but then she was freezing; her body felt warm but then she was freezing; was sick and was different and very weak; muscles were sore; This is a spontaneous report from a contactable consumer. A 78-year-old female patient received the second dose of bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE)), via an unspecified route of administration, administered in the left arm on 17Mar2021 12:10 (Batch/Lot Number: EN6207; Expiration Date: 31May2021) as a single dose for covid-19 immunization. The patient's medical history was not reported. There were no concomitant medications. The patient received her first dose of the Pfizer BioNTech COVID19 vaccine on 23Feb2021 (lot number: EN6198 with expiry date 31May2021) for Covid-19 immunization. The patient experienced passed out for a very short period of  time and awakened by total body shaking and it was not just shivers but was uncontrollable shaking on 18Mar2021; her body felt warm but then she was freezing, she was sick and was different and very weak, and muscles were sore in Mar2021. It was further reported that the patient got the 2nd dose of the Pfizer BioNTech vaccine that day on 17Mar2021 and about 12:45am or 1:30am the next morning she was awakened by total body shaking and it was not just shivers but was uncontrollable shaking; the shaking has resolved completely but she is not sure when it resolved but she was shaking for a good while because she can remember being so uncomfortable with her body moving so much which went on for maybe 20 minutes or so when her husband woke up.Patient's husband then woke up and got Ibuprofen and gave it to her and that stopped the shaking which surprised her and she did not know the Ibuprofen would work to stop the shaking that well and the Ibuprofen did work in stopping the shaking. The Ibuprofen stopped the shaking and she can remember to touch her body felt warm but then she was freezing and she does not know what this means but this was not ongoing and resolved when her husband gave her the ibuprofen and she stopped shaking right away which always amazed her that the Ibuprofen worked. She stated fortunately the Ibuprofen stopped her from shaking and she was able to sleep until early morning when she woke up and knew she was sick and was different and very weak; states the weakness was not ongoing and the approximate time the weakness resolved was unknown but she was down the rest of the day and after that she passed out for a very short period of  time and held her head up and stood up and thought wow something was going on and asked where was this coming from and it was not nausea but she was just weak. She has not passed out for a huge amount of time but fortunately she had some towels laying close by and was able to use a towel; states after that she stopped for the rest of the day and only got up to go to the potty and was just so weak and heard that from many people that they just slept afterwards.Caller states her muscles were sore and she realized that was just normal and after the 2nd dose of the vaccine she knew her muscles would probably be sore and this was resolved. She came downstairs and was sitting on a chair and then stood and no longer sat in the chair and her husband knew things were not right with her and her eyes looked funny and she passed out and that never happened to her before and she was passed out for a few moments. Other than the Ibuprofen she did not have treatment and did not go to the emergency room or the HCP office. Patient only took one Ibuprofen and she has a very small body and her husband sometimes takes 2-3 Ibuprofen and she thinks wow that is so many but she herself does not have any medication and she just took one Ibuprofen and it worked; She took the Ibuprofen on 18Mar2021 in the early morning. Fortunately she was in good health. Outcome of the event passed out for a very short period of  time, was awakened by total body shaking and it was not just shivers but was uncontrollable shaking and muscles were sore was recovered in Mar2021, and unknown outcome for the remaining events.