Breathing is worse; Still sick with side effects/ she is still sick and on prednisone; Fast heartbeat; Sometimes the heart skips a beat; Getting really weak; Rash on body; Rash at the arm where the patient got the vaccine; Joint pain; Chills; Headache; Muscle pain; Doctor said to wait for the second dose until after taking prednisone; patient did not get get the second dose of the vaccine on that date; This spontaneous case was reported by a consumer and describes the occurrence of DYSPNOEA (Breathing is worse), ILLNESS (Still sick with side effects/ she is still sick and on prednisone), PALPITATIONS (Fast heartbeat), EXTRASYSTOLES (Sometimes the heart skips a beat) and ASTHENIA (Getting really weak) in a 78-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 017C21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Blood pressure high, Gout and Cholesterol. Concomitant products included METOPROLOL for Blood pressure high, PRAVASTATIN for Cholesterol, ALLOPURINOL for Gout, LORAZEPAM for an unknown indication.    On 22-Jul-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On an unknown date, the patient experienced DYSPNOEA (Breathing is worse), ILLNESS (Still sick with side effects/ she is still sick and on prednisone), PALPITATIONS (Fast heartbeat), EXTRASYSTOLES (Sometimes the heart skips a beat), ASTHENIA (Getting really weak), RASH (Rash on body), VACCINATION SITE RASH (Rash at the arm where the patient got the vaccine), ARTHRALGIA (Joint pain), CHILLS (Chills), HEADACHE (Headache), MYALGIA (Muscle pain), OFF LABEL USE (Doctor said to wait for the second dose until after taking prednisone) and PRODUCT DOSE OMISSION ISSUE (patient did not get get the second dose of the vaccine on that date). The patient was treated with PARACETAMOL (TYLENOL) at a dose of 1 dosage form; PREDNISONE on 14-Aug-2021 at a dose of 1 dosage form and AMOXICILLIN at a dose of 1 dosage form. At the time of the report, DYSPNOEA (Breathing is worse) and ILLNESS (Still sick with side effects/ she is still sick and on prednisone) had not resolved, PALPITATIONS (Fast heartbeat), EXTRASYSTOLES (Sometimes the heart skips a beat), ASTHENIA (Getting really weak), RASH (Rash on body), VACCINATION SITE RASH (Rash at the arm where the patient got the vaccine), ARTHRALGIA (Joint pain), CHILLS (Chills), HEADACHE (Headache) and MYALGIA (Muscle pain) outcome was unknown and OFF LABEL USE (Doctor said to wait for the second dose until after taking prednisone) and PRODUCT DOSE OMISSION ISSUE (patient did not get get the second dose of the vaccine on that date) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Heart rate: high (High) fast heartbeat.     The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) was unknown.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Patient visited the doctor and he mentioned the events was not because of the vaccine.  Patient received the vaccine on a Thursday and was sick Thursday night and Friday and was okay Saturday and night then Sunday it got worse. Patient took extra strength Tylenol.  Patient's scheduled second dose was on 19-Aug-2021.  Patient did not get the second dose of the vaccine on that date. Patient reported that the patient felt too sick to get it.  As per the contact on 23 Aug 2021 patient reported patient was still sick and was advised by the doctor to not take second until after taking the prednisone.  The patient wanted to know whether the patient could take the second dose while the patient was on  prednisone therapy.   Most recent FOLLOW-UP information incorporated above includes: On 16-Aug-2021: Additional information received on 16 Aug 2021 contains new information. Update on treatment medication prednisone and antibiotic unspecified. On 23-Aug-2021: Additional information appended on 23-AUG-2021 contains significant information: new event was updated,  treatment medication was updated. Event severity updated. On 01-Sep-2021: Additional information was updated- event still ongoing.