WASHINGTON -- The FDA has okayed an auto-injector formulation of naloxone (Evzio), intended to expand the use of an agent that can rapidly reverse an opioid overdose.

In a call with stakeholders Thursday, Health and Human Services Secretary Kathleen Sebelius called the auto-injector a "more user-friendly version" of naloxone, which is only currently available in syringe form, although an off-label nasal version has been used in first-responder programs in several cities.

Anyone at risk for overdose can obtain a prescription for the drug, as can family members or caregivers of those at risk, Douglas Throckmorton, MD, deputy directory for regulatory programs at the FDA's Center for Drug Evaluation and Research, said during a separate telephone briefing with reporters.

The device itself gives verbal instructions on how to use it, similar to instructions relayed by automated external defibrillators found in public facilities, FDA Commissioner Margaret Hamburg, MD, said during that call.

Officials emphasized that the final direction is to seek medical care: "We don't want people to have the sense that this is the last thing they need to do," Throckmorton said. "They need to get help."

Since many prescription opioids on the market are long-acting drugs, the naloxone may not work as long as those opioids, so repeat doses may be needed, the agency said.

Several programs around the country have already been placing rescue naloxone in the hands of first responders as well as family and friends of patients who are addicted to opioids.

On the stakeholders' call, Caleb Banta-Green, PhD, MPH, of the University of Washington in Seattle, said current formulations of the drug "have pretty good uptake" given these programs -- although some involve intranasal naloxone, an off-label route of administration.

The FDA said having an on-label version of the drug may be reassuring to first responders who are hesitant to dispense the inhaled formulation.

"This provides another vehicle -- a safe and effective way for first responders who might be reluctant in terms of off-label use," Michael Botticelli, acting director of the Office of National Drug Control Policy, said during the press call.

But concerns linger that giving out naloxone may send the wrong message about encouraging opioid use.

"Clinicians may feel that they can prescribe more safely in high-risk patients," Roger Chou, MD, of Oregon Health and Science University, in Portland, said during the stakeholder call. "That isn't the message we want to put out there."

"The message should be that these drugs are dangerous and should be treated with respect," Chou said. "For people at high risk, just because we have a tool available doesn't mean [clinicians] should jump into prescribing opioids."

Throckmorton said that's not likely to be the case, adding that the FDA's goal remains reducing the problem of addiction and abuse of prescription opioids.

"The approval of this product is great," said Andrew Kolodny, MD, the New York City-based chief medical officer of Phoenix House, an addiction recovery center. "The irony is that if they were to stop approving new opioids like Zohydro, we'd have less need for naloxone."

Evzio won fast-track status from the FDA, and was reviewed in less than 15 weeks, the agency said. Fast-track status negates the need for an advisory committee hearing on the product.