A summary of allegations against U.S. President Donald Trump's pick to head the Department of Veterans Affairs says he recklessly prescribed drugs, had his own private stock of controlled substances and crashed a government car while drunk.

The summary was released by Democrats as the White House rallied behind Dr. Ronny Jackson.

Based on conversations with 23 of Jackson's colleagues and former colleagues, the review says Jackson was nicknamed "Candyman" by White House staff because he would provide prescriptions without paperwork. Drugs he prescribed included Ambien, used for sleep, and Provigil, used to help wake up.

The colleagues and former colleagues also told congressional staffers that there were multiple incidents of drunkenness on duty and said Jackson got drunk at a Secret Service going-away party and wrecked a government car.

Jackson denies allegations against him, including a charge that he crashed a government car while drunk. (Joshua Roberts/Reuters)

Jackson is denying allegations he was involved in a drunken car wreck.

Jackson told reporters at the White House he "never wrecked a car." He adds, "I have no idea where that is coming from." He said he's moving forward with his nomination.

The White House has rallied behind Jackson, pointing to his past work as a physician to Trump and Barack Obama.