NASHVILLE (AP) — Drug overdoses are the single largest cause of accidental deaths in Tennessee, but state health officials hope a new law requiring doctors to check a database before prescribing certain drugs will help change that.

The state's controlled substances monitoring database has been around for several years, but its use has not been mandatory. As of Jan. 1, doctors and others who prescribe drugs will have to be registered with the database. With limited exceptions, they will have to start checking it every time they prescribe opioids (such as Vicodin or Percocet) and benzodiazepines (such as Valium) by April 1.

Also on Jan. 1, pharmacists will have to step up the frequency with which they update the database, going from every 30 days to every seven days.

"We're trying to move towards real-time reporting," state Health Commissioner John Dreyzehner said. "... I want to know what a patient's been taking this month or this week ."

Dreyzehner also said Tennessee is working with other states on agreements to share patient information. That should help with the problem of patients crossing state lines to avoid being identified in the database.

Most states have some sort of prescription monitoring program, although their databases may not be updated as frequently as Tennessee's. And because different databases don't necessarily collect all the same information, it likely will be a challenge in some cases to determine whether a patient with the same name in a different state is the same person.

Still, Dreyzehner is optimistic that the new program will help.

Last year, 1,062 people died from drug overdoses in Tennessee.

"That's more than died in motor vehicle crashes, homicides or suicides," Dreyzehner said. " ... This really is an epidemic and we have to recognize it and treat it that way."

Asked what happens when a doctor finds that a patient has recently been prescri bed similar drugs from a different provider, he said, "That sparks a conversation. I have to assess what they are using it for and why they're using it."

If a doctor believes a patient is diverting pills for resale, the doctor is required to report that to law enforcement.

But some other patients may be getting drugs for legitimate medical reasons and not even realize that the combination of medicines can be dangerous.

Other patients may be addicts that need help.

"If there seems to be a pattern of misuse or abuse, that's an important opportunity to have a conversation with the patient about what they are really doing," he said.

The doctor might refer the patient to treatment.

"They won't always go right away, but we know that people remember what clinicians say and often will act sooner or later."