mast cells they went nuts immediately, within minutes, which added another layer to her illness; as each shot had a prolonged reaction; mast cells they went nuts immediately, within minutes, which added another layer to her illness; This spontaneous case was reported by a patient and describes the occurrence of MAST CELL ACTIVATION SYNDROME (mast cells they went nuts immediately, within minutes, which added another layer to her illness), IMMUNISATION REACTION (as each shot had a prolonged reaction) and CONDITION AGGRAVATED (mast cells they went nuts immediately, within minutes, which added another layer to her illness) in a 74-year-old female patient who received mRNA-1273 (Spikevax) for COVID-19 prophylaxis.    Co-suspect product included non-company product ESTRADIOL (ESTRADIOL TRANSDERMAL SYSTEM) for Osteoporosis and Menopause.    The patient's past medical history included Skin irritation (With use of the Minivelle generic.) and Abdominal migraine. Previously administered products included for Drug use for unknown indication: Vivelle Dot (20 years ago and Fluctuating migraine). Past adverse reactions to the above products included Migraine with Vivelle Dot. Family history included Mast cell activation syndrome (Mast Cell diseases (unspecified)-Lifelong personal and strong family history) since an unknown date. Concurrent medical conditions included Polyethylene glycol allergy, Chronic migraine (Diagnosed during childhood (age unspecified) and they were originally abdominal migraines.), Pernicious anemia (Worsened over the years), Lyme's disease (With coinfections (unspecified). Worsened over the years.), Asthma (Long going non-chronic asthma without reported worsening.), Myalgic encephalomyelitis (Had worsened but no correlation to Minevvel use.) since 2011, Chronic fatigue syndrome (Had worsened but no correlation to Minevvel use.) since 2011, Osteoporosis (Premenopausal Osteoporosis.), Fragrance sensitivity, Menopause, Mast cell activation syndrome, Food allergy and Drug allergy. Concomitant products included ESTRADIOL (MINIVELLE) for Osteoporosis, Menopause and Abdominal migraine, PROGESTERONE for an unknown indication.   On an unknown date, the patient received first dose of mRNA-1273 (Spikevax) (unknown route) 1 dosage form On an unknown date, received second dose of mRNA-1273 (Spikevax) (unknown route) dosage was changed to 1 dosage form. and ESTRADIOL (ESTRADIOL TRANSDERMAL SYSTEM) (Transdermal) .05 milligram. On an unknown date, the patient experienced MAST CELL ACTIVATION SYNDROME (mast cells they went nuts immediately, within minutes, which added another layer to her illness) (seriousness criteria disability and medically significant), IMMUNISATION REACTION (as each shot had a prolonged reaction) (seriousness criterion disability) and CONDITION AGGRAVATED (mast cells they went nuts immediately, within minutes, which added another layer to her illness) (seriousness criteria disability and medically significant). At the time of the report, MAST CELL ACTIVATION SYNDROME (mast cells they went nuts immediately, within minutes, which added another layer to her illness) and IMMUNISATION REACTION (as each shot had a prolonged reaction) had not resolved and CONDITION AGGRAVATED (mast cells they went nuts immediately, within minutes, which added another layer to her illness) outcome was unknown.        For mRNA-1273 (Spikevax) (Unknown), the reporter considered MAST CELL ACTIVATION SYNDROME (mast cells they went nuts immediately, within minutes, which added another layer to her illness), IMMUNISATION REACTION (as each shot had a prolonged reaction) and CONDITION AGGRAVATED (mast cells they went nuts immediately, within minutes, which added another layer to her illness) to be related.    The patient had family medical history (unspecified). It was reported that she was a fibro patient. The caller reported that she also believed her strong family history of disease was related to being 100 percent.  The patient had been on Estrogen patches with oral Progesterone since the age of 49. She had stayed in isolation during the pandemic and did not had COVID. The patient had not crumbled and had no spontaneous fractures. She believed her conditions all worsened if she used any product with polyethylene Glycol (PEG) in it which included her current generic Estradiol Mylan patch and the 3 Moderna Covid vaccine all have PEG. The caller reported that the Estradiol Mylan patches did not stick well, so she used band aids over the patch. The patient had difficulty with reporting timelines and she did not remember much of the timeline, as she stated that her brain did not process fast. The patient did not have the energy to continue talking. Her goal was to quiet her immune system. It was reported that she had 2 Moderna shots and a Moderna booster, but then stopped getting the shots as each shot had a prolonged reaction and her mast cells they went nuts immediately, within minutes, which added another layer to her illness. DEXA scans discontinued. Patient reported being 100 percent homebound due to her current state of health. No treatment medication was provided.  Company Comment :This spontaneous case concerns a 74-year-old female patient with relevant medical history of Mast cell activation syndrome(also family history of mast cell disease), chronic Lymes Disease, co-infections, Asthma, Myalgic Encephalomyelitis, Chronic Fatigue Syndrome, allergies(Polyethylene glycol allergy), menopause, osteoporosis reported, who experienced the serious(Disability/medically significant), unexpected events of Mast cell activation syndrome and Condition aggravated, serious(Disability), unexpected event of Immunisation reaction in the context of a dose mRNA-1273 vaccine in the COVID-19 vaccination series. Latency cannot be assessed since onset date of events and date of vaccination was not disclosed. It was reported that patient was on Estrogen patches with oral Progesterone. Her conditions worsened after use of co suspect generic Estradiol Mylan patch and the 3 Moderna Covid vaccines (all have PEG). It was reported that, she stopped getting the shots as each shot had a prolonged reaction and her mast cells went to nuts immediately, within minutes, which added another layer to her illness. Patient reported being 100 percent homebound due to her current state of health. No information on detailed clinical course with supporting investigations and treatment received was available in the report. The relevant medical history along with family history of mast cell disease remains as confounder to the events. The benefit-risk relationship of mRNA-1273 is not affected by this report.   This case was linked to MOD-2023-704937 (Patient Link).; Sender's Comments: This spontaneous case concerns a 74-year-old female patient with relevant medical history of Mast cell activation syndrome(also family history of mast cell disease), chronic Lymes Disease, co-infections, Asthma, Myalgic Encephalomyelitis, Chronic Fatigue Syndrome, allergies(Polyethylene glycol allergy), menopause, osteoporosis reported, who experienced the serious(Disability/medically significant), unexpected events of Mast cell activation syndrome and Condition aggravated, serious(Disability), unexpected event of Immunisation reaction in the context of a dose mRNA-1273 vaccine in the COVID-19 vaccination series. Latency cannot be assessed since onset date of events and date of vaccination was not disclosed. It was reported that patient was on Estrogen patches with oral Progesterone. Her conditions worsened after use of co suspect generic Estradiol Mylan patch and the 3 Moderna Covid vaccines (all have PEG). It was reported that, she stopped getting the shots as each shot had a prolonged reaction and her mast cells went to nuts immediately, within minutes, which added another layer to her illness. Patient reported being 100 percent homebound due to her current state of health. No information on detailed clinical course with supporting investigations and treatment received was available in the report. The relevant medical history along with family history of mast cell disease remains as confounder to the events. The benefit-risk relationship of mRNA-1273 is not affected by this report.