pituitary apoplexy; This is a literature report.  A 44 year-old male patient received bnt162b2 (Batch/Lot number: unknown) as dose 2, single for covid-19 immunisation. Relevant medical history included: "hypogonadism" (unspecified if ongoing). The patient's concomitant medications were not reported. Vaccination history included: Bnt162b2 (Dose 1), for Covid-19 Immunization. The following information was reported: PITUITARY APOPLEXY (hospitalization), outcome "unknown", described as "pituitary apoplexy". The patient underwent the following laboratory tests and procedures: blood corticotrophin: 7 pg/mL; blood cortisol: 9.3 ug/dL, notes: at 5am; blood follicle stimulating hormone: 10.5 IU/l; blood luteinising hormone: 3.3 IU/l; blood prolactin: 1.2 ng/ml; blood thyroid stimulating hormone: 2.90 uiU/mL; body temperature: 103 Fahrenheit; 105.9 Fahrenheit; magnetic resonance imaging head: 4.7cm sellar and suprasellar mas, notes: with optic chiasm compression and left sphenoidal extension; mean arterial pressure: 57; thyroxine free: 1.33 ng/dL; tri-iodothyronine free: 3.88 ng/dL; vital signs measurement: hypotension. Therapeutic measures were taken as a result of pituitary apoplexy, included a tertiary care, endoscopic transsphenoidal resection, steroids and levothyroxine. Additional information from article and clinical course was as follows; INTRODUCTION: Pituitary adenomas are a common, asymptomatic finding in the general population. They are usually diagnosed incidentally on imaging studies. Rarely, pituitary adenomas can progress to pituitary apoplexy, defined as hemorrhage and/or infarction and are often associated with a triggering event. CASE DESCRIPTION: A 44 year old man with a history of hypogonadism presented to the hospital for fevers, chills and blurry vision that started after he received his second COVID-19 vaccine three days prior. The day following his vaccine, he initially developed subjective fevers, chills and myalgia which he self-treated with over the counter analgesics at home. Three days after the vaccine, he developed blurry vision along with change in mental status which brought him to the hospital. When he initially presented to an outside hospital, vital signs showed hypotension with MAP of 57 and fever of 103 degrees fahrenheit. MRI of the head showed a 4.7cm sellar and suprasellar mass with optic chiasm compression and left sphenoidal extension. Labs at the time showed FSH 10.5 IU/L, LH 3.3 IU/L, Prolactin 1.2 ng/mL, Cortisol 9.3 ug/dL at 5am, ACTH 7 pg/mL, TSH 2.90 uIU/mL, free T4 1.33 ng/dL and free T3 3.88 ng/dL. Due to the patient's hypotension and findings on imaging studies, there was concern for adrenal insufficiency and the patient was started on stress dose steroids. He was transferred to a tertiary care center and vitals at the time were significant for a temperature 105.9 degrees fahrenheit but otherwise hemodynamically stable. He underwent an endoscopic transsphenoidal resection of the pituitary tumor given compression of the optic chiasm. Pathology report was consistent with pituitary adenoma with focal hemorrhage and necrosis of pituitary adenoma cells. Patient currently remains on maintenance dose steroids and levothyroxine. DISCUSSION: Pituitary apoplexy can occur either spontaneously or due to a stressful trigger. There have been no case reports showing the novel COVID-19 vaccine leading to pituitary infarction or hemorrhage. Although the pathophysiology is not entirely clear, our patient may have developed a robust immune response that  could have potentially been a trigger leading to a pituitary apoplexy.  No follow-up attempts are possible; information about lot/batch number cannot be obtained. No further information is expected.; Sender's Comments: The information currently provided is too limited to make a meaningful medical assessment hence, the events are conservatively assessed as related to the suspect drug BNT162B2 conservatively. This impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly to regulatory authorities, Ethics Committees, and Investigators, as appropriate.