Patrick J. Kennedy is a former congressman and author of The Mental Health Parity and Addiction Equity Act. Mehmet Oz, MD is co-founder of Sharecare and host of "The Dr. Oz Show." Linda Rosenberg is president & CEO of the National Council for Behavioral Health. Marla Weston, PhD, RN, is CEO of the American Nurses Association. The opinions expressed in this commentary are theirs.

As you set priorities for your upcoming administration, we urge you to focus energy and resources on addressing a public health crisis plaguing our country's citizens: addiction -- and, in particular, opioid addiction.

Let's start with the larger problem: Nearly 21 million Americans today suffer from a substance use disorder involving alcohol or drugs, with almost 2 million of those laying their addiction at the feet of a prescription opioid -- medicines such as Vicodin, Percocet and OxyContin, obtained legally and under the advice of their doctor.

However, prescription opioid usage doesn't stay within the realm of legality for long. Whether it's the high cost or difficulty of refilling prescriptions once misuse is suspected by a medical professional, research shows prescription opioid abusers often turn to heroin.

Heroin bears a very similar chemical structure to opioids, binds to the same group of receptors in the brain and ultimately produces the same result in the body: an increase in pain tolerance and a sense of euphoria.

Dr. Mehmet Oz

In three separate studies conducted this year by the National Institute on Drug Abuse (NIDA), nearly half of young people surveyed who inject heroin reported abusing prescription opioids before starting to use heroin.

Through extensive research, the NIDA has further concluded that as many as 80% of today's heroin addicts began their abuse history with prescription drugs.

Linda Rosenberg

And whether one's opioid addiction is to prescription or illegal drugs, the consequences are dire: of the over 40,000 Americans that die each year from drug overdoses, more than half of those deaths involve opioids

Marla Weston

We cannot dismiss these victims of addiction as thrill-seekers or "junkies;" they are people, our fellow Americans -- from blue-collar workers to white-collar executives, to homemakers and even health care professionals -- many of whom sought legitimate medical care for very real health problems. They are our parents, our spouses, our children, our siblings, our grandparents, our friends and our neighbors.

Despite our country's knowledge, resources and wealth, we have failed to adequately address as a nation the epidemic that grips them. Why? Because we have allowed addiction to carry with it the stigma of moral failure instead of calling it what it actually is: a chronic disease of the brain.

Efforts to address addiction as a public health crisis have been severely hampered by this stigma, as well as politics and fear at every level. In the 1980's, the HIV/AIDS epidemic showed us first hand the damage this stigmatization and fear can do to our nation and its citizens. We must learn from our past and not repeat these mistakes, which cost the lives of millions of Americans.

Photos: Celebrities who died from painkillers, cocaine and heroin Comedian and actor John Belushi, known for his early work on "Saturday Night Live," died in 1982 after a "speedball," a combination of heroin and cocaine injected together via the same syringe. He was 33 years old. Hide Caption 1 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Australian actor Heath Ledger, star of "A Knight's Tale," "Brokeback Mountain" and the Batman sequel "The Dark Knight," died in 2008 of a prescription drug overdose . He was 28. Opiates such as oxycodone (OxyContin) and hydrocodone (Vicodin) were found in his system, along with alprazolam (Xanax), diazepam (Valium) and two insomnia drugs. Hide Caption 2 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Actor River Phoenix collapsed and died outside Johnny Depp's West Hollywood nightclub on October 31, 1993, after consuming morphine and cocaine. He was 23 years old. Hide Caption 3 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin The King of Rock 'n' Roll, Elvis Presley, was found dead in his bathroom on August 16, 1977. At the time, his death was attributed to a heart attack, but later investigations found multiple prescription drugs in his system, including the opioid codeine. Elvis was 42 years old. Hide Caption 4 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Rock superstar Prince, known as "The Purple One," died at his Paisley Park home in Minnesota in April of what the medical examiner called a "self-administered" overdose of the painkiller fentanyl, one of the most powerful of all opioids. Prince was 57 years old. Hide Caption 5 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Oscar-winning actor Philip Seymour Hoffman died in February 2014 from a mixture of the opioid heroin and cocaine , benzodiazepines and amphetamines. He was 46. Hide Caption 6 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin "Glee" actor and singer Cory Monteith died of an overdose of heroin mixed with alcohol in July 2013. Monteith had a history of drug use and rehabilitation attempts. He was 31 years old. Hide Caption 7 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Paul Gray, bassist for the metal band Slipknot, died of an overdose of morphine and fentanyl in 2010. He was 38 years old. Hide Caption 8 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Comedian and actor Chris Farley, who launched his career on Saturday Night Live, died in December 1997 of a combination of the opioid morphine and cocaine, complicated by heart disease. He was 33 years old. Hide Caption 9 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Considered one of the premier female rock singers of her time, Janis Joplin was found dead in her apartment on October 4, 1970, from an overdose of heroin. She was 27 years old. Hide Caption 10 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Country music legend Hank Williams died in the back seat of his Cadillac in 1953 of an overdose of morphine and alcohol while being driven to a concert. The story goes that he was injected by a doctor with vitamin B12 and morphine, an opioid painkiller, before climbing into the car with a bottle of whiskey. Hide Caption 11 of 12 Photos: Celebrities who died from painkillers, cocaine and heroin Psychiatrist Sigmund Freud died of an overdose of morphine, given to him by his doctor at his request. Freud had been fighting a malignant cancer of the mouth for years, which was finally deemed inoperable. He was 83. Hide Caption 12 of 12

Instead of approaching our fear of the addiction epidemic with a "Forget Everything and Run" philosophy -- like we did with HIV/AIDS and even cancer just 20 years ago -- we must instead "Face Everything and Recover."

The first ever report, "Facing Addiction in America," just released by our nation's surgeon general , provides us -- and you, President-elect Trump, as our nation's 45th president -- with a non-partisan, science-based opportunity to galvanize the public, policymakers and health-care systems to work together and ensure substance use disorders at all levels of severity can be effectively addressed with the skill, urgency and compassion they require.

From Surgeon General Murthy's report, we have learned that prevention works; treatment is effective; and recovery is possible for everyone, with more than 25 million Americans currently in remission from substance use disorder and living healthy, productive lives.

From the report, we also have learned that substance misuse costs our country $442 billion annually in health-care expenditures, lost productivity and criminal justice costs. By integrating substance use disorder services into general health care, we can yield better outcomes for individuals and our country at large, with studies showing that every dollar spent on substance use disorder treatment saves $4 in health-care costs and $7 in criminal justice costs.

While science tells us how to solve this problem, we need you and other elected officials to help marshal the resources to take on this public health crisis. We applaud the attention you placed on the issue of prescription drug abuse during your campaign for president, and appreciate you stating your commitment to making this a part of your health care policy agenda. And, now it's time for action.

As our president, you can help address addiction in American communities by calling for the strengthening of prevention programs and increasing access to treatment.

This means making evidence-informed policy and program changes at both the federal and state levels; and providing additional training for health-care professionals to explore less addictive treatments for pain than opioids -- and to become better at recognizing the signs of addiction and subsequently treating it.

We also urge you to explore forging public-private partnerships -- such as the one between the Office of the Surgeon General and "Facing Addiction" -- so the American people understand that no one remains unaffected, regardless of age, race, sexual preference, creed, religion or tax bracket, thus shattering that stigma that has paralyzed our progress to date.

Simply put, there is no reason we shouldn't approach addiction with the same focus and determination we do diabetes, heart disease or cancer.

Each of us -- the authors of this letter -- have dedicated our life's work to helping people live their healthiest lives, and lead platforms and organizations which every week, respectively, reach more than 60 million online health consumers and millions of daytime television viewers; 10 million adults, children and families living with mental illnesses and addictions; and the nation's 3.6 million registered nurses.

As such, we feel compelled to speak as one unified front, and implore you, the 45th president of the United States, to make addiction a top priority in your administration. With millions of American lives on the line, how we respond to this crisis is a moral test for America; and how our next president responds to this crisis is a moral test for you, Mr. Trump.