sick for 6 days; lost weight; This is a spontaneous report received from contactable reporter(s) (Other HCP). The reporter is the patient. Other Case identifier(s): MOD22-011813 (Moderna).  A 72-year-old female patient received BNT162b2 (BNT162B2), on 04Oct2021 as dose 3 (booster), single (Lot number: 301358A) at the age of 72 years for covid-19 immunisation. The patient's relevant medical history included: "allergy to mostly pollen" (unspecified if ongoing), notes: She has allergy to mostly pollen which she already had for the last 10-12, years. There were no concomitant medications. Vaccination history included: BNT162b2 (Dose number: 01, Manufacturer: Pfizer, Lot number: EL9265, She reports that she did not have any side effect after getting the 1st dose of the Pfizer vaccine.), administration date: 12Feb2021, when the patient was 71-year-old, for COVID-19 Immunization, reaction(s): "she did not have any side effect"; BNT162b2 (Dose number: 02, Manufacturer: Pfizer, Lot number: EN6203, But the 2nd dose knocked her flat. She was sick for 6 days and lost weight.), administration date: 04Mar2021, when the patient was 71-year-old, for COVID-19 Immunization, reaction(s): "sick for 6 days"; BNT162b2 (Dose number: 02, Manufacturer: Pfizer, Lot number: EN6203, But the 2nd dose knocked her flat. She was sick for 6 days and lost weight. She had similar side effects after getting the 1st booster dose (Pfizer) but these only lasted for 24 hour.), administration date: 04Mar2021, when the patient was 71-year-old, for Covid-19 immunization, reaction(s): "lost weight"; Flu shot (She had her flu shot in Aug2021 or Sep2021.), administration date: 2021. The following information was reported: WEIGHT DECREASED (non-serious) with onset Oct2021, outcome "unknown", described as "lost weight"; ILLNESS (non-serious) with onset Oct2021, outcome "unknown", described as "sick for 6 days". Relevant laboratory tests and procedures are available in the appropriate section.  Additional Information: A retired physician assistant reports she had terrible side effects after getting the 2nd booster dose of the Moderna Covid-19 vaccine. She said she is sure she is not only person who experienced side effects  but there are people around the world who have had the same experience. She thinks that there will be other variations of the vaccines developed against the other variants and she does not want to take them anymore in the future if she will have the same side effects. Or if anyone can call her to advise her on what she can do to mitigate the side effects of these vaccine. She says she is not an anti-vaxxer but her side effects were really horrible. She reports that she did not have any side effect after getting the 1st dose of the Pfizer vaccine. But the 2nd dose knocked her flat. She was sick for 6 days and lost weight. She had similar side effects after getting the 1st booster dose (Pfizer) but these only lasted for 24 hour. After she got the 2nd booster dose (Moderna) - she got it because that was the only brand available at that time - she got horribly sick again for 24 hours (the terrible part lasted for 24 hours - she was able to get up from bed but she still had the symptoms). The most prominent symptom was horrible neck pain and head ache. She knows that this is caused by the inflammation of her cervical spine nerves and she knows because of the dermatome that is affected - right shoulder, arm, forehead and neck. She already had this before but it got aggravated after she got her injection. She took Ibuprofen 400mg-600mg but did not give her relief. The pain was terrible that she wanted to get an appointment with her pain management provider but was not able to get one and it resolved on its own. She also had chills without fever she was so cold that she wore clothes to bed she also had some fatigue and some nausea which was very similar to when she got the 2nd dose of Pfizer. Her daughter who is in the genetics field said that she could have a certain HLA type which could cause her to have the reaction to the Pfizer vaccine but now she is thinking this could also be the same reason why she is reacting the same way after getting the Moderna vaccine. She sates that it is something intrinsic that must have caused her to react this way. She is 5ft 5inch in height. She has allergy to mostly pollen which she already had for the last 10-12 years. She has not had any Covid-19 diagnosis, no concomitant medical conditions. She had her flu shot in Aug2021 or Sep2021. She reports that she did not have any side effect after getting the 1st dose of the Pfizer vaccine. But the 2nd dose knocked her flat. She was sick for 6 days and lost weight. She had similar side effects after getting the 1st booster dose (Pfizer) but these only lasted for 24 hour. After she got the 2nd booster dose (Moderna) - she got it because that was the only brand available at that time - she got horribly sick again for 24 hours (the terrible part lasted for 24 hours she was able to get up from bed but she still had the symptoms). The most prominent symptom was horrible neck pain and head ache. She knows that this is caused by the inflammation of her cervical spine nerves and she knows because of the dermatome that is affected - right shoulder, arm, forehead and neck. She already had this before but it got aggravated after she got her injection. She took Ibuprofen 400mg-600mg but did not give her relief. The pain was terrible that she wanted to get an appointment with her pain management provider but was not able to get one and it resolved on its own. She also had chills without fever she was so cold that she wore clothes to bed she also had some fatigue and some nausea which was very similar to when she got the 2nd dose of Pfizer. Her daughter who is in the genetics field said that she could have a certain HLA type which could cause her to have the reaction to the Pfizer vaccine but now she is thinking this could also be the same reason why she is reacting the same way after getting the Moderna vaccine. She sates that it is something intrinsic that must have caused her to react this way. She is 5ft 5inch in height. She has allergy to mostly pollen which she already had for the last 10-12 years. She has not had any Covid-19 diagnosis, no concomitant medical conditions. She had her flu shot in Aug2021 or Sep2021. She reports that she did not have any side effect after getting the 1st dose of the Pfizer vaccine. But the 2nd dose knocked her flat. She was sick for 6 days and lost weight. She had similar side effects after getting the 1st booster dose (Pfizer) but these only lasted for 24 hour. After she got the 2nd booster dose (Moderna) - she got it because that was the only brand available at that time - she got horribly sick again for 24 hours (the terrible part lasted for 24 hours she was able to get up from bed but she still had the symptoms). The most prominent symptom was horrible neck pain and head ache. She knows that this is caused by the inflammation of her cervical spine nerves and she knows because of the dermatome that is affected - right shoulder, arm, forehead and neck. She already had this before but it got aggravated after she got her injection. She took Ibuprofen 400mg-600mg but did not give her relief. The pain was terrible that she wanted to get an appointment with her pain management provider but was not able to get one and it resolved on its own. She also had chills without fever she was so cold that she wore clothes to bed she also had some fatigue and some nausea which was very similar to when she got the 2nd dose of Pfizer. Her daughter who is in the genetics field said that she could have a certain HLA type which could cause her to have the reaction to the Pfizer vaccine but now she is thinking this could also be the same reason why she is reacting the same way after getting the Moderna vaccine. She sates that it is something intrinsic that must have caused her to react this way. She is 5ft 5inch in height. She has allergy to mostly pollen which she already had for the last 10-12 years. She has not had any Covid-19 diagnosis, no concomitant medical conditions. She had her flu shot in Aug2021 or Sep2021.  No follow-up attempts are possible. No further information is expected.