In response to the ongoing crisis of opioid misuse, U.S. doctors had already cut the amount of opioids they gave patients after surgery by 2022 to just a third of the amount given in 2016, new research shows.

Much of the decline happened before the pandemic, however, and the rate at which doctors are reducing the use of post-op opioids has slowed.

The use of opioids during surgery recovery is a well-known gateway to opioid addiction.

“The goal should be to ensure that opioids are only prescribed when necessary, and that the amount of opioids prescribed matches the amount that patients need,” study lead author Jason Zhang said in a University of Michigan news release.

“Achieving these goals could help reduce the risk of opioid misuse, persistent opioid use and diversion of pills to other people besides the patient," added Zhang, who worked on the study while a research assistant at the University of Michigan. He's now a med student at Northwestern University in Chicago.

The new study was published Dec. 7 in JAMA Network Open.

Zhang's team looked at 2016-2022 entries from a U.S. database that comprises 92% of all retail pharmacy prescriptions written in those years.

They found that surgery-linked opioid prescriptions fell by 36% during that time period, and the average amount of opioids included in those prescriptions also fell by 46%.

Taken together, that means that the overall amount of opioids prescribed to Americans after their surgeries fell by 66% between 2016 and 2022, the Michigan group concluded.

However, the bulk of this decline occurred early — between 2016 and 2019 — followed by a slowdown in the rate of decline in opioid prescriptions during and after the pandemic.

That means that "efforts to right-size opioid prescriptions after surgery must continue," said study senior author Dr. Kao-Ping Chua, an assistant professor of pediatrics at the University of Michigan.

The study also found that some types of surgeons were cutting back on opioid prescribing more than others. Heart and eye surgeons made especially tough cutbacks on dispensing post-op opioids, the data showed, but rates remained relatively high among orthopedic surgeons.

Half of the opioids still given to patients after a surgery are related to orthopedic surgeries, the research showed.

Besides the risks of addiction posed to patients, having unnecessary opioids at home could raise the odds of drug abuse by others in the household, the research team noted. Opioids can also interact dangerously with alcohol or other drugs.