Less common side effects
Once getting the vaccine, a person should generally stay for 15 to 30 minutes at the vaccination location so that health workers are available in case of any sudden adverse reactions.
You should alert your doctor after getting vaccinated if you experience any adverse side effects or any other health events. This especially goes for side effects lasting more than 3 days.
Some less common side effects reported for COVID-19 vaccines have included severe allergic reactions like anaphylaxis shock. However, this reaction is incredibly rare.
National and international bodies, including WHO, have been closely monitoring for any unexpected side effects following vaccine use.