trouble breathing; fuzzy feeling; Itching eyes; feeling like bugs under skin; her allergic reaction began about 4 hours later/ allergic reaction for binders is getting worse; This is a spontaneous report from a contactable consumer (Patient). A 64-year-old female patient received first dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE; Solution for injection; Lot number: EN6207, expiry date: unknown), via an unspecified route of administration on arm left on 26Mar2021 10:00 (age at vaccination: 64 years) as dose 1, single for COVID-19 immunization. The patient medical history included allergic reaction (she is allergic to some medication binders, and is allergic to the ethanol glycol that is in the Pfizer COVID-19 vaccine), thyroid surgery, Open heart surgery. The patient reported that that she has a thyroid medication that she has been taking for over 20 years, after they took half of her thyroid out. She says that they found out about her binder medication allergy when she had open heart surgery for a birth defect when she was 55. She says she had an allergic reaction in the hospital to those meds, which they said was to the binders, but they didn't know which ones because she was on more than one medication at the time, so she avoids medications period. She says she doesn't know which medications those were, there were seven and they removed them all at one since she was having a severe reaction at that point, and they had been giving them IV. She says they removed all 7 and said to just watch. She says that she is allergic to one binder, ethanol glycol, which is one used for this vaccine, but she may be allergic to other ones also, she just knows she is allergic to that one. The patient stated that she did not had any other recent vaccinations or started any new medications. The patient Concomitant medications reported as yes. On 26Mar2021, the patient experienced Fuzzy feeling, Itching eyes, feeling like bugs under skin, trouble breathing. It was reported that she received the first dose of the Pfizer-BioNTech COVID-19 Vaccine, and reported to have had an allergy to the "binders" used. Caller stated that this is only "suspected but did not know for sure" she clarified that it wasn't an anaphylactic reaction. It started right away, but "was very very light" and ended 9 hours later. During the last half-hour, she stated that she had trouble breathing. The patient asked, "if I take Benadryl, will that have an effect on the vaccine?" she reported that her first dose of the vaccine was injected around 10:00 AM, and her allergic reaction began about 4 hours later. She says when it became known that was what was happening, she was having a fuzzy feeling before that but nothing definite, she knew it was an allergic reaction 4 hours later when she had itching eyes and feeling of bugs under her skin, which is her normal allergic reaction to binders. She says the allergic reaction for binders is getting worse when she has them, and that time her reaction went on for another 5 hours, then after that it then went away when the binder went out of her system. She clarifies the allergic reaction gets worse every time she takes meds with binders in them, though some meds aren't available without binders, like vaccines. She says in the past for treatment she took Benadryl, one of them, which the product calls for two, but she took one. She clarifies she didn't take anything with the COVID-19 vaccine because she didn't know if it would make anything worse and she wasn't having trouble breathing except for a half hour. She says if her trouble breathing had continued she would have taken something, but it went away so she didn't take anything this time because she was afraid it would interact and it didn't get bad enough to where she couldn't breathe. She says she would like to know if she has trouble with the second dose, when should she take Benadryl? It was reported there was product complaint.  Description of complaint was reported as Allergic to ingredient/binder in Pfizer COVID-19 vaccine: Caller says that they found out about her binder medication allergy when she had open heart surgery for a birth defect when she was 55. She says she had an allergic reaction in the hospital to those meds, which they said was to the binders, but they didn't know which ones because she was on more than one medication at the time, so she avoids medications period. She says she doesn't know which medications those were, there were seven and they removed them all at one since she was having a severe reaction at that point, and they had been giving them IV. She says they removed all 7 and said to just watch. She says that she is allergic to one binder, ethanol glycol, which is one used for this vaccine, but she may be allergic to other ones also, she just knows she is allergic to that one. She says the allergic reaction gets worse every time she takes meds with binders in them, though some meds aren't available without binders, like vaccines. Treatment received as a result of trouble breathing was reported as no. The outcome of trouble breathing, allergy aggravated was recovered on an unknown date in 2021. The outcome of her allergic reaction began about 4 hours later was resolving, while outcome of other events was unknown.  Follow-up attempts completed. No further information expected.