PULMONARY EMBOLI; PLEURAL EFFUSION; MUSCULOSKELETAL PULL; PATIENT RECEIVED APIXABAN 5MG BID INITIALLY FOR CLOTS IN RIGHT LEG, BILATERAL PE; FEVER; DIZZINESS; OFF BALANCE; This is a spontaneous report received from a contactable reporter(s) (Other HCP) from License Party(Agency). Other Case identifier(s): US-BRISTOL-MYERS SQUIBB COMPANY-BMS-2022-031479 (Agency).  This case was received via Pfizer Inc (Reference number: 202200334494) on 25-Feb-2022 and was forwarded to Agency on 28-Feb-2022. This spontaneous case was reported by an other health professional and describes the occurrence of Prescribed Underdose (Patient received apixaban 5mg BID initially for clots in right leg, bilateral PE) in 44-year-old male patient who received apixaban (ELIQUIS) for DVT and Pulmonary embolism. Previously administered products included for Pulmonary embolism: Xarelto (Bilateral PE and pleural effusion) from 11-Nov-2021 to 10-Dec-2021; for DVT: Warfarin (MCL tear and DVT in right leg in DEC-2008). Past adverse reactions to the above products included Dizziness with Xarelto. Concurrent medical conditions included Blood disorder (On blood thinners since Sep-2009). On 11-Dec-2021, the patient started ELIQUIS (Oral), 5 milligram twice a day. On the same day, the patient experienced prescribed underdose (Patient received apixaban 5mg BID initially for clots in right leg, bilateral PE). The action taken with ELIQUIS(Oral) was unknown. At the time of the report, prescribed underdose outcome was unknown. Diagnostic Results (normal ranges are provided in parenthesis if available): On 11-Nov-2021, Computerised tomogram: Positive evidence of acute PE, Fibrin D dimer: 686 ng/mL  reference range: less than 244 ng/mL, Haematocrit (40-52 percent): 43.2 percent, Haemoglobin (13.3-17.7 gram per decilitre): 14.8 gram per decilitre and Platelet count (150-400 per millilitre): 237 per millilitre. On 06-Dec-2021, Computerised tomogram: Decreased clot burden in right upper lobe. On 09-Dec-2021, Computerised tomogram: No Acute intracranial hemorrhage or apparent acute transcortical infarction, no mucosal thickening. On an unknown date, Ultrasound Doppler: DVT and X-ray: Bilateral PE and pleural effusion. For ELIQUIS(Oral), the reporter did not provide any causality assessments.  Causality Assessment:  Drug: ELIQUIS,  Event: Prescribed underdose Per Reporter: No Information   Per Agency: Not Related    Eliquis is under agreement with Agency.  Follow-up (14Mar2022): This is a spontaneous follow-up report received from a contactable reporter(s) (Consumer or other non HCP) from License Party. Other Case identifier(s): US-BRISTOL-MYERS SQUIBB COMPANY-BMS-2022-031479 (Agency).  This case was received via {Agency} Pfizer Inc (Reference number: 202200334494) on 25-Feb-2022. Information was received from a Consumer/other non health professional concerning a 44 Year(s) old Male patient, who received Suspect product APIXABAN for PE and DVT, Oral (5 milligram(s) 2 every 1 Day), lot number:Unknown; Suspect product BNT162B2 for product used for unknown indication, lot number:Unknown. On 12-Nov-2021, the patient experienced balance disorder(off balance) which was considered serious due to the following criteria: disability and medical significance. Treatment included Treated by reducing apixaban dosing from 20 mg to 10 mg along with Meclizine 12.5 mg dose and had eye examination. Follow up was suggested with ENT specialist to complete vestibular and cochlear freqency testing..The patient had not yet recovered. On 12-Nov-2021, the patient experienced dizziness(dizzines) which was considered serious due to the following criteria: disability and medical significance. The patient had not yet recovered. On 12-Nov-2021, the patient experienced pyrexia(fever) which was considered not serious. It is unknown if treatment was provided. The outcome of the event is unknown. On 11-Dec-2021, the patient experienced prescribed underdose(patient received apixaban 5mg bid initially for clots in right leg, bilateral pe) which was considered not serious. It is unknown if treatment was provided. The outcome of the event is unknown.On an unknown date, the patient experienced pulmonary embolism(pulmonary emboli) which was considered serious due to medical significance. It is unknown if treatment was provided. The outcome of the event is unknown. On an unknown date, the patient experienced pleural effusion(pleural effusion) which was considered not serious. It is unknown if treatment was provided. The outcome of the event is unknown. On an unknown date, the patient experienced musculoskeletal pain(musculoskeletal pull) which was considered not serious. It is unknown if treatment was provided. The outcome of the event is unknown. The status of APIXABAN medication is unknown. The status of BNT162B2 medication is unknown. Medical history and concurrent conditions included null, Blood disorder (continuing), COVID-19 immunisation (from 06-Sep-2021), Pulmonary embolism (from 02-Dec-2008 until 01-Feb-2009) and Thrombectomy (not continuing, from Dec-2008). Concomitant medications were not reported. Relevant Laboratory & other Diagnostic Tests On 11-Nov-2021, CT OF CHEST: *Positive evidence of acute PE, D-DIMER: *686 ng/mL . Normal range is <244 ng/mL, HAEMATOCRIT: 43.2 % percent(normal 40 to 52), HEMOGLOBIN: 14.8 gram per decilitre(normal 13.3 to 17.7), PLATELET COUNT: 237 per millilitre(normal 150 to 400). On 06-Dec-2021, CT: *Decreased clot burden in right upper lobe. On 09-Dec-2021, CT: *No Acute intracranial hemorrhage or apparent acute transcortical infarction, no mucosal thickening,. On an unknown date, DOPPLER: *DVT, X RAY: *Bilateral PE and pleural effusion. The reporter did not provide a causal assessment for events balance disorder, dizziness, pulmonary embolism, pyrexia, prescribed underdose, pleural effusion and musculoskeletal pain to product APIXABAN. The reporter did not provide a causal assessment for events balance disorder, dizziness, pulmonary embolism, pyrexia, prescribed underdose, pleural effusion and musculoskeletal pain to product BNT162B2. Tracking of Changes: 25-Feb-2022: Initial information was received. Follow up received on 14-Mar-2022 with the following updates:  Eliquis is under agreement with Agency.  Causality Assessment:  Drug: ELIQUIS,  Event: Pulmonary embolism, Dizziness, Balanced difficulty, Pleural effusion, Musculoskeletal pain, Fever, Prescribed underdose Per Reporter: No Information   Per Agency: Not Related    Causality Assessment:  Drug: BNT162B2 Event: Pulmonary embolism, Dizziness, Balanced difficulty, Pleural effusion, Musculoskeletal pain, Fever, Prescribed underdose Per Reporter: No Information   Per Agency: Related  Agency Comment: This patient developed multiple events after receiving apixaban. Based on limited information regarding definitive diagnosis and relevant medical history, the reported events off balance and dizziness are considered not related to apixaban. Past history of pulmonary embolism  and underlying thromboembolic risk are significant risk factors for another episode of pulmonary embolism, hence considered not related to apixaban.; Sender's Comments: Agency Comment: This patient developed multiple events after receiving apixaban. Based on limited information regarding definitive diagnosis and relevant medical history, the reported events off balance and dizziness are considered not related to apixaban. Past history of pulmonary embolism  and underlying thromboembolic risk are significant risk factors for another episode of pulmonary embolism, hence considered not related to apixaban.