Unwanted effects of the Moderna Covid vaccine: fatigue, headache, muscle ache

Tony Potts, a 69-year-old retiree who lives in Ormond Beach, will receive his first injection as a participant in a Moderna-sponsored Phase 3 COVID-19 clinical vaccine trial on August 4, 2020 at Accel Research Sites in DeLand, Florida.

Paul Hennessy | NurPhoto | Getty Images

Fatigue, headaches, and muscle aches are the most common side effects of Moderna’s Covid-19 vaccine, along with some rare symptoms such as persistent nausea or vomiting and facial swelling that are likely caused by the gunfire. That is based on new data released Tuesday by Food and Drug Administration.

On the positive side, people over 64, who are also among the most severely affected by the disease, were generally better tolerated than younger people.

Vaccine side effects are common. It’s actually an immune response that indicates the shots are working as intended, doctors say. Many doctors advise the public to prepare for some more severe side effects than usual with the Covid-19 injections than, say, a typical flu shot, and possibly to take a day or two off to recover.

Moderna’s vaccine, which was approved by FDA officials on Tuesday, is more than 94% effective and safe enough to meet agency requirements for an emergency, according to the report. However, the regulator’s analysis found that the vaccine was associated with common and unpleasant, but not necessarily dangerous, side effects.

More than 9 out of 10 participants who received the vaccine felt pain at the injection site, nearly 7 out of 10 felt tired, and about 6 out of 10 had a headache or muscle pain, the FDA said.

More than 44% of people who received the vaccine reported having joint pain and over 43% reported having chills. The FDA found that more serious “serious side effects” occurred in 0.2% to 9.7% of participants, “occurring more often after the second dose than after the first. Like Pfizer’s Covid vaccine that the FDA approved last week, Moderna’s vaccine also requires two shots, separated by a few weeks.

According to the FDA, nearly 15% of vaccine participants had a fever after the first or second dose.

Some side effects were tough to shake, although most were resolved within a week, the FDA said. Less than 6% reported symptoms that lasted for at least a week after the shot, but that were similar to the placebo group. Some of the study participants had a fever that lasted for more than a week. Seven were in the vaccine group and four were given the placebo, the FDA found.

The FDA said there were seven “serious adverse events” in the study, but none of them were fatal. Four were attributed to the vaccine by investigators and Moderna, including persistent nausea and vomiting, facial swelling, and rheumatoid arthritis.

The FDA staff also recommended that people receiving the vaccine be monitored for possible cases of Bell’s palsy. This isn’t necessarily a side effect, but it’s worth looking out for now that four of the 30,000 participants in the study contract this condition, which causes half of your face to fall off.