Rep. Ronny Jackson (R-TX) said he would "demand" that President Joe Biden take a test for performance-enhancing drugs before the debate on Thursday.

On Sunday, Jackson told Fox News host Maria Bartiromo that he was sending a letter to the White House.

"So tomorrow, I'm sending a letter to President Biden, to his physician, Dr. O'Connor, and I'm CCing his entire cabinet," Jackson explained. "And it's embarrassing that I have to do this."

"But I'm going to be demanding on behalf of many millions of concerned Americans right now that he submit to a drug test before and after this debate, specifically looking for performance-enhancing drugs," he continued.

Jackson offered a conspiracy theory to explain reports that Biden was spending time at Camp David to prepare for Thursday's CNN debate.

"I feel like this is probably what's going on over this week at Camp David," he said. "Part of that is probably experimenting with just getting the doses just right, because they have to treat his cognition. They have to give him something to help him think straighter. They have to give him something to wake him up for his alertness."

"And so they're probably going to give him something to take the edge off that as well," he added. "They didn't get it right just last time at the State of the Union."

"He came out. He was obviously much more alert. But he was a yelling, angry old man."

According to a recent report, Jackson was known for taking sleeping pills and drinking alcohol while he was serving as White House physician for Presidents Trump and Barack Obama.