Second Dose Side Effects – What to Expect

Depending on where they live, many older adults have received or are scheduled to receive their second dose of a COVID-19 vaccination and they may be wondering how severe the side effects will be or if no reaction means they aren’t as well protected. 

Each person will react differently to a novel coronavirus vaccine but according to immunologists and infectious disease specialists, in clinical trials of the Pfizer and Moderna vaccines, regardless of side effects, two weeks after the second dose study participants were about 95 percent protected against the disease. 

The most commonly reported Pfizer effect after dose two was fatigue and about 80 percent of those who received the second dose of the Moderna vaccine had either fever, fatigue, or muscle pain, according to a recent MedPage Today report.  That still leaves a substantial number of people who will experience no side effects, yet just because they don’t have fatigue or a sore arm doesn’t mean they aren’t well protected.  It is also suggested that because participants who received a placebo also reported fatigue frequently, the number of people experiencing side effects may be somewhat inflated. 

Although the Centers for Disease Control and Prevention does not advise taking any over-the-counter medication before getting vaccinated, you can talk with your doctor about using ibuprofen, acetaminophen, aspirin, or antihistamines for any pain or discomfort after getting vaccinated.   A clean, cool washcloth over the area of the vaccine and moving the arm may help relieve any discomfort and plenty of fluids and light clothing will help manage a fever.  

Any side effects of COVID-19 vaccination should go away within a day or two.  But if redness or tenderness at the site of the injection worsens after 24 hours or other side effects are not improving after a few days, contact your healthcare provider.  Side effects of a second dose may be more intense but this is a good sign that your body is building a defense against the disease. 

Even after you have been fully vaccinated, it’s still important to take precautions like wearing a mask in public spaces, avoiding crowds, staying 6 feet away from others, and washing your hands frequently.  As researchers learn more about the spread of COVID-19, recommendations will be updated. 

Read more about authorized COVID-19 vaccines in Canada, how they work, ingredients, allergies, possible side effects, and safety monitoring here