Methadone appears safe and effective in treating people who use fentanyl, suggests a study presented at the recent annual meeting of the American Society of Addiction Medicine.

“Highly potent fentanyl – often in combination with other substances including alcohol and benzodiazepines – is highly dangerous and responsible in large part for the enormous spike in preventable drug overdose deaths,” said lead researcher Andrew Stone, M.D., Medical Director of Discovery House CTC of Northern Rhode Island. “We conducted this study to see if medication-assisted treatment is effective in treating those who use fentanyl, given its unique properties and extreme potency.”

Stone and colleagues performed urine drug screens on patients admitted to a methadone maintenance treatment program over a 10-month period. Patients were screened for substances including illicit fentanyl, opiates and methadone. Those who tested positive for fentanyl when entering the program appeared to require a slightly higher dose of methadone to reach abstinence. The relapse rate for those who did not test positive for fentanyl was 15 percent, compared with 41 percent for those who tested positive. Most relapses while in treatment involved fentanyl, regardless of which substances were found in the initial drug screen. “The greater relapse rate may be due to the inability of methadone to completely block the ‘high’ users experience with fentanyl,” Dr. Stone said.

There were no deaths among patients who remained in treatment, suggesting methadone appears to be safe even in people who relapse on fentanyl.

“We were hoping we’d see a dramatic response if we upped the dose of methadone high enough, but based on our results, we don’t think methadone alone is enough to completely eradicate fentanyl use,” Dr. Stone said. “We will need to use a combination of medication-assisted treatment and behavioral changes. This study suggests it’s safe to continue methadone treatment while working on the behavioral change necessary to get to prolonged and sustained abstinence.”

Addiction treatment providers have been concerned about the safety of using methadone to treat fentanyl use, primarily because of the question of what happens if a person relapses and starts using fentanyl while still taking methadone, Dr. Stone said. “People develop tolerance to the respiratory depressant effects of opioids over time. Long-acting opioids like methadone and buprenorphine maintain this tolerance, thus preventing respiratory failure in those who use heroin or other opioids during a relapse. Because fentanyl is so potent, providers have been worried that if they give a patient a large enough dose of methadone to improve withdrawal symptoms and that person relapses, will it kill them? No one knew the answer. Now we know that fentanyl on top of methadone isn’t deadly – the tolerance effect appears to persist in people using methadone and fentanyl.”

Dr. Stone advises all addiction treatment providers to test for fentanyl in patients who use opioids. “More and more areas will see this epidemic come to them and unless they are screening for it on the front lines (in ERs and drug treatment programs). Needless deaths will occur that could have been prevented,” he said. “The good news is that treatment appears to work at least for saving lives.”