RELATED: The CDC Director Says If You Want a Booster, Don’t Do This Right Now. Leana Wen, MD, an emergency physician and professor of health policy and management at the George Washington University Milken Institute School of Public Health, told CNN that since a lot of people seem confused about the latest guidance on boosters, it’s important to clarify that there is a difference between who should get an additional shot and who is simply eligible for it. Anyone who gets a third dose must have already received two shots of the Pfizer vaccine and be at least six months out from that second dose, but Wen clarified that there are only three groups of people the FDA and CDC have explicitly advised to get a booster: those moderately or severely immunocompromised, those who are 65 years or older, and those who are 50 years or older with an underlying medical condition that puts them more at risk for severe COVID. “Those people are advised to get a third Pfizer dose, and should,” she said. But there is a broader group of people who are eligible to get the booster, despite not falling into these three groups. The FDA and CDC also determined that anyone over the age of 18 who has an underlying medical condition or is at high risk because of occupational or institutional reasons can get a booster as well. “These individuals aren’t necessarily advised to get the booster, but they may, once they weigh their own risks and benefits in consultation with their physicians,” Wen explained. CDC Director Rochelle Walensky, MD, also discussed the agency’s decision to advise some people to get a booster but still allow others the opportunity to get another shot as well. “We made it possible for people to be eligible, but they really have to identify their own individual risk and they own their own individual benefit,” Walensky said during a Sept. 26 interview on CBS’ Face the Nation. As Wen said, you shouldn’t have to complete this risk-benefit analysis on your own. “You don’t have to guess. You can talk to your doctor, you can talk to your pharmacist, go to somebody who can understand, who knows your healthcare history and can help you make a smart, wise decision,” Nina Radcliff, MD, a physician anesthesiologist, told The National Desk. According to Wen, there is clear data that indicates that a booster shot would benefit older adults and reduce their likelihood of getting infected with COVID and severe illness. But the CDC advisory panel “essentially said that the benefit-risk calculation is a little less clear for those who are in the second, broader group,” she noted, adding that current vaccine protection against this group “still appears strong against severe infection.” RELATED: For more up-to-date information, sign up for our daily newsletter. Per the CDC, the side effects reported so far after the Pfizer booster shot appear similar to those experienced after the first two shots. Pain at the injection site and fatigue were the most common reactions, and most side effects tended to be mild to moderate. Even so, the reason certain people are allowed but not encouraged to get the booster is because there is still some risk, albeit very small. “As with the 2-shot primary, serious side effects are rare but may occur,” the CDC states. These most concerning of the severe reactions is myocarditis, which is inflammation of the heart muscle that is more common in male adolescents and young adults.ae0fcc31ae342fd3a1346ebb1f342fcb “It’s important to note that the myocarditis associated with the mRNA vaccines is generally mild and resolves with no long-term harm—and that COVID itself can cause myocarditis,” Wen noted. “Still, especially if you are a younger male, but also if you are in the ‘may’ versus ‘should’ category, it is always a good idea to have a conversation with your doctor about the risks versus benefits of the vaccine.” RELATED: Dr. Fauci Says Doing This Could “Defeat the Purpose” of Your Booster.