Scientists Examine Pain Relief and Addiction

[April 15, 2007, AJHP News]

Donna Young

BETHESDA, MD, 30 March 2007 — With the abuse of prescription opioids on the rise, health care practitioners are grappling with the challenge of providing patients adequate pain relief without addiction, said Walter F. Stewart, director of the Geisinger Center for Health Research in Danville, Pennsylvania.

Opioid medications are generally prescribed for short-term use, Stewart said. But, he noted, the powerful narcotics are increasingly being prescribed for long-term use, particularly in the primary care setting.

Unfortunately, no clinical model exists for chronic care use of prescription opioids, Stewart told an audience of researchers, health care professionals, and consumers on March 5 in Bethesda, Maryland, at a National Institute on Drug Abuse (NIDA) symposium about the potential for addiction in patients with chronic pain conditions.

Practitioners prescribing opioid therapy for long-term use, he said, must rely on guidelines that "are largely based on consensus."

But, Stewart said, "These guidelines assume an idealized care model, which doesn't exist in reality."

Since the mid-1990s, over 1500 health care guidelines directed at primary care practitioners have been issued, he maintained.

"So primary care physicians are besieged with . . . what is humanly impossible for them to learn," Stewart declared. He urged groups that develop guidelines to "boil them down to some key ingredients."

About 3% of the U.S. adult population use prescription narcotics long term to treat pain, Stewart said, adding that many of those patients, particularly those who are elderly, have other chronic conditions and are taking other medications.

Of great concern, he said, are the long-term opioid users who are taking other medications that affect the brain, such as antidepressants, stimulants, and antipsychotics.

"These classes of drugs are relatively common among opioid users," Stewart noted.

But, he said, there is little clinical evidence available for practitioners facing the challenge of managing the therapy of patients taking opioids and other drugs.

Clinical trials, he noted, are restricted to relatively healthy adults. That limitation, Stewart contended, has created a "knowledge gap" between what is known about treatment in an "idealized" setting and the "reality of primary care."

"So anywhere from 70% to 90% of patients who are eventually prescribed an approved drug would have been excluded from those trials," he argued. "It's probably even more significant or severe with regard to opioids. We know relatively little about the possible interactions of a number of factors. There's a complexity here that we know relatively little about."

Also challenging, Stewart said, is that many primary care physicians are not up-to-date in their training and knowledge about newer opioids.

David F. Musto, professor of child psychiatry at Yale University's Child Study Center in New Haven, Connecticut, and a medical historian, expressed concern that inadequate knowledge about the proper use of opioids contributes to the problem of abuse of those products.

That lack of knowledge, he said, can also lead to physicians inadequately treating pain because of a fear that a patient may become addicted to a narcotic pain reliever.

Musto argued that because of the recent focus on prescription drug addiction, there is a growing trend among clinicians not to use opioids.

"This trend is not unprecedented," he said.

In the 19th century, opiates were not regulated and used in abundance for almost every ailment, Musto noted, adding that hypodermic syringe sets for opiate use were even advertised to consumers in the Sears Roebuck catalog.

But after the enactment of the Harrison Narcotics Act of 1914—the first U.S. law to regulate opioids—the drugs went from being called "God's own medicine" to being characterized as products used by criminals, he said.

Physicians were jailed in the 1920s and 1930s for prescribing the drugs. By the 1950s, penalties for violating federal narcotics laws included the death penalty, Musto said.

"We had moved from practically no controls over narcotics in the 19th century, when physicians were seen as providers of a wonderful and almost harmless drug, to a powerful fear of opioids and of physicians," he said.

But, Musto said, because of an "overzealous" reaction to the opiate addiction problem that plagued the nation in the early 20th century, greater restrictions on narcotics led to many patients being undertreated for pain.

Musto said he was worried that the current concern about prescription drug abuse will lead to a backlash against opioid use, resulting in patients once again being inadequately treated.

"The physician becomes more hesitant to prescribe, the patient to accept the drugs," he said.

The campaigns against prescription drug abuse, Musto urged, should include the recognition of the legitimate medical uses of opioids.

"Without this effort, the growing antidrug movement may again unintentionally impede humane treatment of those in pain and distress," he said.

Scientists have identified many of the biological and environmental factors that lead to drug addiction and are searching for the genetic variations that contribute to the development and progression of addiction, said Mary Jeanne Kreek, head of Rockefeller University's Laboratory of the Biology of Addictive Diseases.

She was part of a team that hypothesized in 1964 that opiate addiction is a metabolic disease of the brain. That hypothesis, she noted, led to the development of the first methadone maintenance treatment program.

"We have learned a great deal about addictions and about how to manage them," Kreek said. "But there is more to learn, and, equally, we have to be sure that what we have learned can be properly utilized."

NIDA Director Nora D. Volkow said that scientists are working on developing a new class of opioid pain relievers that curb the potential for abuse and are researching new methods for treating addiction.

She noted that her agency is funding a study to test the effectiveness of buprenorphine–naloxone tablets, or Suboxone, along with different models of drug counseling in patients addicted to prescription opioids.

The Prescription Opiate Addiction Treatment Study, or POATS, will be carried out at 11 sites across the country.

Participants will include patients with chronic pain who have become addicted to opioid medications, such as oxycodone, and people who have abused painkillers for nonmedical reasons.

Participants enrolled in the study will be treated with Suboxone for one month at the outset. They will then be stabilized and the dosage tapered off as part of a detoxification process. If a participant remains abstinent for two months, the person will complete the study. If the participant relapses and begins abusing prescription opiates again, the person may be eligible to resume the medication therapy for three more months, taper off during a fourth month, and monitored for two months.

To compare the effectiveness of various behavioral therapies in conjunction with the medication, half the study participants will be enrolled in an intensive personal drug counseling program. The other half will receive a brief drug counseling session from their physicians.