SEMINOLE COUNTY, Fla. — Some people who didn’t get Pfizer for the first two doses are wondering now whether they can mix and match with a Pfizer booster shot. 

What You Need To Know

  •  The CDC approved recommendations last week to offer a third dose of the Pfizer COVID-19 vaccine for certain people

  •  Moderna and Johnson & Johnson have not yet been approved to be able to officer a booster of their vaccines

  • In general, doctors do not recommend mixing vaccines, but say high risk individuals can still talk to their provider about the possibility

  • RELATED: CDC study: Side effects from 3rd booster dose similar to those from 2nd dose

“Aqua aerobics helped me lose 200 pounds, so I cannot complain — 60 more pounds to go,” said Seminole County resident Holly Horton. 

Health and fitness are very important to her. 

That’s why she never misses a day of water aerobics at the gym and why she wants to get a booster shot.

But she can’t right now because she got the Moderna vaccine. 

“They haven’t approved the Moderna yet and I don’t want to mix my medicines, they say on the internet that you shouldn’t mix your medicines, so the minute Moderna says it’s OK, I’m there in line,” she said. 

Associate Professor of Infectious Diseases at University of Florida Health Dr. Kartik Cherabuddi agreed and said he’s advising his patients to not mix and match booster shots. 

“I’m holding off on that for my own patients, and would advise the others to do the same,” Cherabuddi said. 

Despite that recommendation in the U.S., giving Pfizer booster shots to people who originally received a different brand is already happening in some European countries and Canada. 

While it's not advised in the U.S., Cherabuddi said some people in especially high-risk situations who can’t wait, should consult their doctor about mixing other types with a Pfizer booster. 

“Say you’re 70 years old and you’ve taken one dose of the J&J vaccine … or you’re 66 year old and you’ve taken two doses of the Moderna and you also have heart disease and obesity … I think that’s a discussion you want to have with your individual doctor,” he said. 

Horton considered mixing a Pfizer booster with her Moderna vaccine, but after some research she plans to hold off. 

“I’m kind of wishing they gave me the Pfizer now — oh what the hey, you know, I’ll just wait,” she said. 

So for now she’ll just stick to hitting the gym every day. 

At a press briefing Tuesday Dr. Anthony Fauci said research data on mixing a Pfizer booster with other vaccines is not expected to be available until mid-October.