hypertensive crisis; high blood pressure for one week; NAUSEA; Headache; This spontaneous case was reported by a nurse and describes the occurrence of HYPERTENSIVE CRISIS (hypertensive crisis) and HYPERTENSION (high blood pressure for one week) in a 65-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 018B21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included Lymphoma (2-3 years ago.), Clot blood (After pacemaker procedure) in July 2018, Arrhythmia, Pacemaker insertion (cardiac) in July 2018, Cardiac resynchronization therapy (CRT procedure in her left arm) in 2018, Defibrillator/pacemaker insertion (defibrillator implant) in 2018 and Catheterisation cardiac (cardiac catheter procedure) in 2018. Concurrent medical conditions included Atrial fibrillation, Cardiomyopathy and Heart failure. Concomitant products included PROPAFENONE (RYTHMOL [PROPAFENONE]), ATENOLOL (TENORMIN), ALUMINIUM HYDROXIDE, MAGNESIUM TRISILICATE, SODIUM ALGINATE (PEPCID [ALUMINIUM HYDROXIDE;MAGNESIUM TRISILICATE;SODIUM ALGINATE]), LEVOTHYROXINE SODIUM (SYNTHROID), APIXABAN (ELIQUIS), BUMETANIDE (BUMEX), POTASSIUM, MAGNESIUM and LORAZEPAM (ATIVAN) for an unknown indication.    On 10-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 10-Apr-2021, the patient experienced HYPERTENSIVE CRISIS (hypertensive crisis) (seriousness criteria hospitalization and medically significant), HYPERTENSION (high blood pressure for one week) (seriousness criterion hospitalization) and HEADACHE (Headache). On an unknown date, the patient experienced NAUSEA (NAUSEA). The patient was treated with SPIRONOLACTONE ongoing since an unknown date at a dose of 25 milligram twice a day; AMLODIPINE ongoing since an unknown date at a dose of 5 milligram twice a day; SACUBITRIL VALSARTAN SODIUM HYDRATE (ENTRESTO) ongoing since an unknown date at a dose of 1 dosage form twice a day; ATENOLOL (TENORMIN) ongoing since an unknown date at a dose of 200 milligram once a day; LORAZEPAM (ATIVAN) ongoing since an unknown date at a dose of 1 milligram four times per day and BUMETANIDE (BUMEX) ongoing since an unknown date at a dose of 1 milligram once a day. At the time of the report, HYPERTENSIVE CRISIS (hypertensive crisis), HYPERTENSION (high blood pressure for one week), HEADACHE (Headache) and NAUSEA (NAUSEA) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In April 2021, Blood pressure measurement: 250/140 (High) 250/140 mmHg and 290/145 (High) 290/145 mmHg. In 2021, Blood electrolytes: below normal (Low) below normal. In 2021, Inflammatory marker test: high (High) High. In 2021, Monocyte count: high (High) High.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Patient reported that she has been hospitalized four or five times since 10-Apr-2021. Additionally, she reported a weight gain of approximately 20lbs that was related to her medication.  Patient stated that she has seen her Cardiologist and Primary Care Physician many times since the vaccinations. She mentioned that her treatment medications are now maintenance medications added to her other medications she has already been taking.  Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.   This case was linked to MOD-2021-244669 (Patient Link).; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.