RELATED: Don’t Get Your Booster at CVS Before Doing This, Pharmacy Says. As of Oct. 20, the FDA has authorized the use of Moderna, Pfizer, and Johnson & Johnson vaccines as single-dose boosters for eligible recipients. “A single booster dose of any of the available COVID-19 vaccines may be administered as a heterologous booster dose following completion of primary vaccination with a different available COVID-19 vaccine,” the FDA said in a statement. RELATED: This Is What Experts Want You to Know About the Moderna Booster. According to the FDA, patients who received the Johnson & Johnson shot as their initial vaccine may receive a single booster dose of J&J, Moderna, or Pfizer if they are age 18 or over and received their initial J&J shot at least two months ago. The booster eligibility guidelines for those who initially received the Modern or Pfizer vaccine are different, however. If you received the Moderna or Pfizer shots as your initial vaccine, you’ll have to wait a bit longer to receive a booster. The FDA says that Moderna or Pfizer vaccine recipients may receive a single dose of booster of J&J, Moderna, or Pfizer once at least six months have passed since their second dose of the two-dose series. Patients will also still have to meet at least one of the following criteria to be eligible for a booster: They are 65 years of age and older, 18 through 64 years of age at high-risk of severe COVID-19, or 18 through 64 years of age that work in high-risk settings. While data is limited, experts say there is no evidence that receiving a booster from a brand different than the one that made your initial COVID vaccine is dangerous or harmful. In fact, a recent study presented to the CDC tracked people who received mix-and-match boosters and no severe or adverse events related to the vaccines were reported, The Washington Post reported on Oct. 21. There is still much research to be done in order to collect substantial evidence on what the benefits are of mixing and matching boosters. However, early studies have shown that in the case of patients who received the J&J shot as their initial COVID-19 vaccine, receiving a booster made by Moderna or Pfizer may actually provide a higher level of antibodies. “If you look at the level of antibodies that are induced—if you originally had J&J, and you get, for example, a Moderna or a Pfizer, the level of antibodies, namely, the proteins that you would predict would protect you, those levels go up higher with the Moderna boost to J&J than the J&J boost,” Anthony Fauci, MD, chief medical adviser to the White House, explained during a recent appearance on ABC’s This Week. Most experts seem to agree that while there may be some potential added benefits to mixing and matching vaccines, it’s by no means necessary. More important than anything else is to get vaccinated, and if you are vaccinated, get a booster whenever you are eligible to receive one. All vaccines and their single booster dose have proven to be effective at protecting against COVID-19. “Under almost all circumstances, we should say that the Pfizer and Moderna vaccines are generally interchangeable,” Leana Wen, MD, an emergency physician and public health professor at George Washington University, said in a recent interview on PBS’ News Hour. “There’s no particular reason to switch from Pfizer or Moderna to one of the others. And, really, there are very few circumstances that they should be switching to a J&J vaccine.” For more helpful health information sent straight to your inbox, sign up for our daily newsletter. While the FDA and CDC have both authorized the use of all three brands of vaccine as single-dose boosters, neither agency has provided official advice regarding mixing and matching. That’s why, it’s best to discuss what option is best for you with your doctor, Mohammad Sobhanie, MD, an infectious disease expert at The Ohio State University Wexner Medical Center, told AARP recently.ae0fcc31ae342fd3a1346ebb1f342fcb “I think it’s incredibly important that you have these conversations with your primary care physician so that they can give you the best advice out there based on your medical conditions,” he said. RELATED: This Is What Experts Want You to Know About the Pfizer Booster.