About 5,000 active and retired FDNY employees are receiving medical treatment for injuries and illnesses connected to the World Trade Center attacks, according to a Fire Department document.

“That is an absolutely staggering number, and it’s a number that speaks volumes,” said Andrew Carboy, a lawyer who represents more than 200 firefighters in a negligence suit against the city. “That’s half of what the force was on 9/11.”

The FDNY had about 11,000 members on Sept. 11, 2001.

About 3,000 firefighters and EMS workers are receiving counseling for emotional problems. Another 1,500 are suffering respiratory ailments.

There are also between 600 and 1,000 FDNY members – most of whom retired after 9/11 – currently receiving prescription medication for a variety of illnesses, from asthma and gastrointestinal disease to depression and anxiety.

The shocking numbers were revealed in a June 8 FDNY “request for proposals,” launched in search of a vendor to manage the department’s prescription-drug program for five years.

The department announced in February that it will use millions of dollars in federal funds to help subsidize medication for workers suffering from 9/11-related injuries, allowing them to obtain free prescription drugs.

Although all 5,000 workers suffering from ailments – who were all screened by the FDNY – are eligible for the program, many are using workers’ compensation or other forms of insurance to obtain medication.

There are 207 drugs approved in the program, including antidepressants Prozac, Zoloft and Paxil; anti-anxiety medication Xanax; narcotic painkiller OxyContin; and antipsychotics Haldol and Zyprexa, which are used to combat schizophrenia and bipolar disorder.

“When 5,000 members of the FDNY qualify for these kinds of medications, it’s clear this problem isn’t going to go away anytime soon,” said Stephen Cassidy, president of the Uniformed Firefighters Association.

“People tend to forget, or maybe it’s just human nature, to put that event behind you,” he said. “But firefighters, many of whom lost many, many friends that day, besides the physical injuries, still suffer severe emotional pain.”

angela.montefinise@nypost.com