These "immune effects" include pain where the needle went in, fever, chills, headache, fatigue and body aches. They can last for a few hours up to a few days. Acetaminophen or ibuprofen can ease these side effects, but these medicines should be taken after receiving the vaccine.
There is a remote chance that the Moderna COVID-19 Vaccine could cause a severe allergic
reaction. A severe allergic reaction would usually occur within a few minutes to one hour after
getting a dose of the Moderna COVID-19 Vaccine. For this reason, your vaccination provider
may ask you to stay at the place where you received your vaccine for monitoring after
vaccination. Signs of a severe allergic reaction can include:
• Difficulty breathing
• Swelling of your face and throat
• A fast heartbeat
• A bad rash all over your body
• Dizziness and weakness
The most commonly reported side effects by individuals who received a booster dose of the Moderna COVID-19 Vaccine after completion of a two-dose primary series were pain, redness and swelling at the injection site, as well as fatigue, headache, muscle or joint pain and chills.
You probably experienced COVID-19 vaccine side effects fairly quickly when you had your initial injections. The same is true for COVID-19 vaccine booster shots: Most people notice side effects within the first 24 hours. The symptoms typically only last a day or two. Some people don't notice any side effects.
Side effects that have been reported with the Janssen COVID-19 Vaccine include: Injection site reactions: pain, redness of the skin, and swelling. General side effects: headache, feeling very tired, muscle aches, nausea, fever. Swollen lymph nodes.
“Overall, severe allergic reactions to COVID-19 mRNA vaccines, including life-threatening anaphylaxis reactions such as low blood pressure and difficulty breathing, are rare, on the order of five cases per million vaccine doses administered,” noted Dr. Guerrerio.
Tell your doctor right away if you have a rash, itching, a fast heartbeat, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth after receiving the vaccine.