her speech returns to normal; received the booster or 3rd dose of the vaccine; received the booster or 3rd dose of the vaccine; This is a spontaneous report from a contactable consumer (patient). A 42-years-old female patient received third dose of bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Solution for injection, Lot Number: FF2588),via an unspecified route of administration, administered in left arm on 05Sep2021 at 13:00 hours as DOSE 3 (BOOSTER), SINGLE (at the age of 42-years-old) for COVID-19 immunisation. The patient's medical history included ongoing myasthenia gravis from 2017 (gave her the chronic symptom of slurred speech). Concomitant medications included pyridostigmine bromide (MESTINON); prednisone; thymomodulin (IMURONG); immunoglobulin human normal (I.V.-GLOBULIN) and mycophenolate mofetil hydrochloride (CELLCEPT [MYCOPHENOLATE MOFETIL HYDROCHLORIDE]) taken for myasthenia gravis.The patient previously received first dose of bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Solution for injection, Batch/Lot Number: EW0150),via an unspecified route of administration, on 01Apr2021 at 04:00 PM as DOSE 1, SINGLE (at the age of 42-years-old) and second dose of bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Solution for injection, Batch/Lot Number: FW0175),via an unspecified route of administration, on 23Apr2021 at 10:00 AM as DOSE 2, SINGLE (at the age of 42-years-old) for COVID-19 immunization.It was reported that after each dose of vaccine, speech returned to normal and lasts about a week before it starts to fade. The patient with the relief of her symptoms felt like pre-sick self. The patient would like to know whether anyone else has reported this benefit from vaccination.The patient was immunocompromised and does have a chronic illness that illness was slurred speech where she could not say the number 3 or the number 6 and since she has had the 3rd dose of the vaccine, she no longer has slurred speech and could speak a lot more clearly and things were a lot better.The patient was waiting for her home nurse to come give her IVIG that she gets every three weeks and even the nurse was impressed, and she felt great after the vaccine and also mentioned this to her doctor, and she was like a needle in a haystack and with how she felt at the time of reporting. The patient felt like she might have a shot at life and felt like she did before she got sick and clarified by sick she was diagnosed with myasthenia gravis.The patient did not know what was helping her but it was something and stated does it fade and the answer was yes regarding the improvement in her slurred speech but this time she was monitoring her speaking and the speech was clear and she was not getting tired and with myasthenia gravis which she clarified was diagnosed before the vaccine in 2017 she had been on disability and whether having this shot feels like this more often she may get her life back and she had a lot of weakness and everything with her myasthenia gravis.The patient stated that the improvement in slurred speech waxes and wanes and fluctuates with her speech and before she was sick, and her speech has never been this strong or clear.The patient stated began to speak clearly after the 3rd dose of the vaccine was about 24 hours after she had the vaccine; the patient was normally a sensitive person and was nervous enough and did not have other vaccines administered the same date as the Pfizer COVID Vaccines; has been on the same medications that are immunosuppressants and started on those medications since she was diagnosed or after her diagnosis with myasthenia gravis; started accruing the medications over time when she was diagnosed and they are for the myasthenia gravis; was first started on Mestinon and went from that and they added Prednisone and Imuron. she tried Cellcept first and had been on the Imuron maybe a year and a half or two years.The patient was immunocompromised and her times of being on the Imuron maybe off due to COVID; caller clarified she was not diagnosed with COVID and has no lots, expiry dates or NDC numbers to provide for the Mestinon, Cellcept, Prednisone, or Imuron. The patient had no prior vaccinations within 4 weeks of Pfizer vaccine. The event her speech returns to normal was ongoing (not recovered). The clinical outcome of other events was unknown.  Follow-up attempts are completed. No further information is expected.