President Donald Trump pulled his nomination of Dr. Janette Nesheiwat as U.S. surgeon general Wednesday just a day before she was expected to appear before the Senate for her confirmation hearing.

Dr. Casey Means is the new pick, Trump said in a Truth Social post.

"Her academic achievements, together with her life's work, are absolutely outstanding," he wrote. "Dr. Casey Means has the potential to be one of the finest Surgeon Generals in United States History."

Means' brother, Calley Means, serves as White House senior adviser and special government employee who has worked closely with Kennedy and has touted many of his health proposals.

Nesheiwat, who came under fire from right-wing influencer Laura Loomer, will serve with Health and Human Services Secretary Robert F. Kennedy Jr. in another capacity, Trump said.

She said in a statement on X that she is looking forward to working with Kennedy to "Make America Healthy Again!"

"My focus continues to be on improving the health and well-being of all Americans, and that mission hasn't changed," she said.

Nesheiwat was a frequent Fox News medical contributor and worked as a physician at the Times Square CityMD urgent care clinic before becoming one of its medical directors.

Bloomberg first reported the move earlier Wednesday.

Casey Means helped launch the health tech company Levels and has co-written self-help books that pushed for more nutrition-based health remedies.

She and her brother came to the attention of conservative influencers following an interview with Tucker Carlson last summer.

The shakeup comes as Loomer called on the president to pick a new nominee after it came to light that Nesheiwat received her medical degree from American University of the Caribbean instead of the University of Arkansas. Loomer also criticized Nesheiwat for being pro-vaccine.

Initially, Nesheiwat promoted the COVID-19 vaccine, calling it "a gift from God" in a 2021 opinion piece for Fox News, but a year later, she opposed the vaccine mandates for children during an appearance on Carlson's Fox News show despite medical studies showing that the COVID-19 vaccine can greatly reduce the chance for severe symptoms, hospitalization and death from the virus for patients of all ages.

Trump praised Nesheiwat during his November announcement, calling her a "fierce advocate and strong communicator for preventive medicine and public health."

The White House has not responded to ABC News' requests for comment.

Nesheiwat is the sister-in-law of former national security adviser Mike Waltz, who was removed from his post last week and nominated to be the U.S. ambassador to the United Nations.

Waltz came under fire after it was revealed he was part of a Signal group chat with national security team members, including Defense Secretary Pete Hegseth, in which they discussed impending military plans and inadvertently invited The Atlantic Editor-in-Chief Jeffrey Goldberg to the chat.

Loomer also called for Waltz to be fired after the scandal.

She has become a more prominent figure in Trump's inner circle and made recommendations to Trump on whom to fire, sources told ABC News last month.

"She makes recommendations of things and people, and sometimes I listen to those recommendations, like I do with everybody," Trump said last month. "I listen to everybody, and then I make a decision. But I saw her yesterday. She was at the ceremony, and she is -- she'll always have something to say, usually very constructive."