According to the Las Vegas Review-Journal, Stephen Paddock, the man responsible for the most deadly mass shooting in the history of the country, was prescribed anti-anxiety medication a few months before his horrific shooting spree that resulted in 59 people dead and over 500 injured. The drug, diazepam, can lead to psychotic episodes and aggressive behavior; however, one expert suggests that an adverse reaction to the drug alone would not explain Paddock's "very planned" actions.

"Records from the Nevada Prescription Monitoring Program obtained Tuesday show Paddock was prescribed 50 10-milligram diazepam tablets by Henderson physician Dr. Steven Winkler on June 21," the Review-Journal reports. "Paddock purchased the drug — its brand name is Valium — without insurance at a Walgreens store in Reno on the same day it was prescribed. He was supposed to take one pill a day."

Records show that Winkler had prescribed diazepam to Paddock last year, though the prescription was for two tablets a day rather than one.

While diazepam is used to treat anxiety, it can also trigger dangerous side effects, including increased anxiety, hallucination, and aggressive behavior. Also among the list of side effects are decreased inhibitions, unusual risk-taking behavior, suicidal thoughts, hostility, confusion, and depression.

The Review-Journal spoke with the chief medical officer at the Las Vegas Recovery Center, Dr. Mel Pohl, who said that the drug Paddock was prescribed can sometimes heighten a preexisting problem, like "underlying aggression."

"If somebody has an underlying aggression problem and you sedate them with that drug, they can become aggressive," Dr. Pohl told the paper. “It can disinhibit an underlying emotional state. … It is much like what happens when you give alcohol to some people … they become aggressive instead of going to sleep.”

But another expert told the paper that he doubts Paddock's actions can be entirely explained by an adverse reaction to the drug. Columbia University's Dr. Michael First, an expert on benzodiazepines, said that while benzodiazepines like diazepam can result in aggressive behavior, the extent to which Paddock planned his actions suggests he had deeper underlying issues that were the true motivation driving his heinous act.

Why he was prescribed the drug to begin with, said Dr. First, “may have more to do with why he did what he did."

Read the full report here.

Several recent mass shooters have been on psychiatric drugs with similarly dangerous side effects. Here's a lengthy list from a drug watchdog group of school shooters who were on psychiatric drugs.

More from The Daily Wire on Paddock:

Las Vegas Shooter's 'Psychopathic' Father Was On FBI's Most-Wanted List

REPORT: Las Vegas Shooter Filmed Himself During Massacre

REPORT: Las Vegas Shooter May Have Originally Targeted A Different Music Festival