In 2018, Arizona lawmakers began requiring clinicians who prescribe high doses of opioids to also prescribe naloxone, the overdose-reversal medication commonly known by the brand name Narcan.

It was a new effort to increase access to naloxone during the opioid epidemic and, according to researchers at the University of Arizona, it worked.

Research led by James Cunningham, a professor in the Department of Family and Community Medicine in the College of Medicine – Tucson, found that Arizona's law was associated with a pronounced increase in naloxone prescribing for patients receiving high-dose opioids.

But the impact didn't stop there.

"The increase wasn't limited to patients covered by the law," Cunningham said. "Naloxone prescribing also increased for patients receiving moderate doses of opioids. Pharmacists also sharply increased naloxone dispensing to patients who had opioid prescriptions but had not been prescribed naloxone, even though pharmacist dispensing wasn't addressed by the law."

A 'life-saving medication'

According to the National Institute on Drug Abuse, more than 105,000 people died in 2023 from drug overdoses, and more than 75% of those deaths involved opioids. The Centers for Disease Control recommends prescribing naloxone, which it calls a "life-saving medication" because when someone is experiencing an overdose, naloxone reverses it in more than 90% of cases.

Arizona's law took effect in April 2018 and applied to patients receiving more than 90 morphine milligram equivalents, or MME, of opioids per day. To measure its impact, Cunningham and the study's co-authors – including Beth Meyerson, director of the Harm Reduction Research Lab in the College of Nursing and the Comprehensive Center for Pain and Addiction; and Jake Greenhalgh, Mehret Girmay and John Riggs with the Arizona Controlled Substances Prescription Monitoring Program – analyzed statewide data from the Arizona Controlled Substances Prescription Monitoring Program, which tracked every opioid prescription dispensed in the state from 2017 through 2022. Because the program records prescriptions when they are dispensed, the data show that patients were not only prescribed naloxone but also picked it up.

The study, published in the American Journal of Preventive Medicine, found that during the first two months after the law took effect, naloxone coprescribing among patients receiving high-dose opioids spiked by 331% among those receiving 90 to 119 MME per day and by 360% among those receiving at least 120 MME per day. It then declined to a level about twice as high as before the law, or 97% and 123%, respectfully. Among patients receiving 50 to 89 MME per day, a moderate dose, coprescribing increased by 215% and then declined to a level 72% higher than before the law.

Pharmacists stepped up too. Arizona already allowed pharmacists to dispense naloxone without an individual prescription through statewide "standing orders." After the law took effect, that dispensing increased by at least 111% across every opioid-dose category, including among patients receiving low doses, and remained elevated for about two years before declining.

By the end of 2022, about 2.3 naloxone prescriptions were being coprescribed for every 100 opioid prescriptions among patients receiving 90 to 119 MME per day, and about 1.5 per 100 among those receiving at least 120 MME per day. Before the law, the rate was roughly 0.5 naloxone prescriptions per 100 high-dose opioid prescriptions. The study noted that an optimal coprescribing level has not yet been established, partly because a new naloxone prescription is not needed with every opioid prescription.

Naloxone became available over the counter nationwide in March 2023, after the study period ended. But Cunningham said prescriptions still matter, particularly for people who may struggle to afford the medication. Many patients who need opioid medications also face financial strain, and a prescription can allow insurance to help cover the cost of naloxone, often $30 to $40.

Increased awareness

The law may also have helped keep naloxone in clinicians' awareness.

"You're in the doctor's office for 10, 15 minutes, and then you're out the door," Cunningham said. "Clinicians have a lot of things competing for their attention, but the regulation helps keep naloxone in the conversation."

The law also reached a group that may have been underserved in terms of access to naloxone.

"Community organizations are doing important work to provide naloxone to people who use opioids, but they often focus on illicit opioid use," Cunningham said. "The coprescribing law helped provide naloxone to patients who might not have gotten it through community organizations."

The study could not determine whether the increase in naloxone prescribing translated into fewer overdoses or deaths. That will require additional research, Cunningham said.

"Certainly, that's the hope," he said.