“I think he’s done more than the previous president, I will say that,” said Ms. Walden, who is now part of a national group to end opioid addiction. She added that she thought there were “some things they aren’t addressing,” and specified the Food and Drug Administration.

Melania Trump, the first lady, traveled with her husband to Atlanta and addressed the conference before he did. She has made opioids one of her signature issues — particularly the toll the crisis takes on babies and mothers — and it is the one public policy initiative that she and the president work on together.

But Mr. Trump did not use his address to focus solely on opioid addiction, instead pivoting to talk about the strength of the economy and a law enforcement crackdown at the southwestern border, with special praise for drug-sniffing dogs.

He also drew a connection between more aggressive interdiction efforts and his long-promised construction of a border wall.

“We’re going to have a wall. It’s going to be a very powerful wall,” he said, adding that it would have a “tremendous impact” on drugs coming into the country, even though most of the illegal drugs get smuggled through legal ports of entry.

In the past 20 years, overdoses caused by prescription opioids have claimed more than 200,000 lives, according to statistics from the Centers for Disease Control and Prevention, with an uptick in recent years in parts of the country where Mr. Trump is popular, like West Virginia and Ohio.

The president declared the opioid crisis a public health emergency in October 2017. By the next October, according to the White House, the Trump administration had raised $6 billion in new funding to address it.