US President Donald Trump has called on a Democratic senator to resign for making allegations against his pick to head the veterans' affairs department.
President Trump had backed his doctor, Ronny Jackson, for the job, but Dr Jackson withdrew his candidacy on Thursday after a flurry of misconduct allegations.
Democrat Jon Tester's office collected the critical testimonies.
Dr Jackson denies all accusations, which the president said are "false".
A two-page document brought together statements by 23 of his colleagues and former colleagues, who called him "flat-out unethical", "toxic", "explosive", "abusive" and "volatile".
Sen Tester said Dr Jackson was nicknamed "the candy man" because he handed out medications "like candy".
On Saturday, Mr Trump posted tweets in support of Dr Jackson, dismissing "phony Democrat charges" and saying "Tester should resign".
Mr Tester, a Montana senator who is a high-ranking member of the Senate Veterans' Affairs committee, has not yet commented. He is up for re-election in Montana in November.
Allegations made by Senator Jon Tester against Admiral/Doctor Ron Jackson are proving false. The Secret Service is unable to confirm (in fact they deny) any of the phony Democrat charges which have absolutely devastated the wonderful Jackson family. Tester should resign. The.....— Donald J. Trump (@realDonaldTrump) April 28, 2018
....great people of Montana will not stand for this kind of slander when talking of a great human being. Admiral Jackson is the kind of man that those in Montana would most respect and admire, and now, for no reason whatsoever, his reputation has been shattered. Not fair, Tester!— Donald J. Trump (@realDonaldTrump) April 28, 2018
Dr Jackson was also accused of getting drunk and wrecking a government vehicle at a secret service party.
The Associated Press reported that the White House has since said that Dr Jackson was involved in three minor incidents in government vehicles, but none involved alcohol and he was not found to be at fault.
The Department of Veterans Affairs is the federal government's second largest department.
A confirmation hearing for Mr Jackson was postponed last week by Mr Tester, who said the claims needed to be investigated.
Rear Admiral Jackson, an Iraq war veteran, has worked as presidential physician to three presidents, serving George W Bush and Barack Obama before Mr Trump moved into the White House.
On Friday, he released a statement announcing his withdrawal. It said: "Unfortunately, because of how Washington works, these false allegations have become a distraction for this president and the important issue we must be addressing - how we give the best care to our nation's heroes."
The last Veterans Affairs Secretary, David Shulkin, was fired by Mr Trump last month following a critical report by an internal watchdog.
It was one in a long line of departures from Mr Trump's cabinet.