Five most common side effects of AstraZeneca, Sinovac vaccines

Metro Manila (CNN Philippines, April 20) — A majority of the side effects of COVID-19 vaccines being rolled out locally were usually mild, the National Adverse Effects Following Immunization Committee (NAEFIC) said Tuesday.

The five most common adverse events of Sinovac's COVID-19 vaccine are elevated blood pressure, headache, injection site pain, dizziness, and rash while the top five side effects of AstraZeneca's shot are fever, headache, injection site pain, chills, and muscle aches.

NAEFIC member Dr. Eileen Cuajunco said the time it takes for adverse events to appear varies, but most of them are "transient" and indicate that the body's immune system is responding to the vaccine.

"The vaccine side effects can appear soon after like if the patient has stress-related response, it can be even less than 5 minutes," she told a briefing.

"If the patient has an allergy, it can be in the next 30 minutes or an hour, it varies and depending on the response, or it can be even like general pain, fatigue, myalgia - the muscle pain that appears 1 to 3 days or as late as 5 to 7 days," she added.

Infectious disease expert Dr. Anna Ong-Lim earlier said a history of severe allergy does not preclude COVID-19 vaccination unless that allergy is to the shot or its ingredients.

The Food and Drug Administration is expected to provide more details on the adverse reactions related to the COVID-19 vaccination program on Friday.

Pre-vaccination advice

Meanwhile, people should not take drugs before getting their COVID-19 vaccine to prevent allergic reactions, the Department of Health said Wednesday.

"We do not recommend taking these drugs prior to vaccination as according to our experts, [they] may dampen the immune system," DOH Undersecretary Maria Rosario Vergeire told CNN Philippines, when asked about those who reportedly take paracetamol or anti-allergy medicine before inoculation.

Over 1.2 million Filipinos have so far received doses of AstraZeneca and Sinovac vaccines. The government is conducting simultaneous vaccination of healthcare workers, elderlies, and people with comorbidities in light of the fresh surge in COVID-19 cases. The government aims to inoculate up to 70 million of the population this year to achieve herd immunity.

CNN Philippines Correspondent Carolyn Bonquin contributed to this report