Dax Shepard started keeping drug tests at home after his recent relapse so Kristen Bell can test him whenever she feels 'nervous'

• Kristen Bell revealed in a new interview that she keeps drug tests at home for husband Dax Shepard.
• Bell said that Shepard told her to test him if she ever feels "nervous" he relapsed.
• "'I want you to have access to this and I'll do it, no questions asked,'" Bell recalled him saying.

Kristen Bell revealed in a new interview with Self that she has drug tests at home and free rein to use them in case she feels "nervous" about husband Dax Shepard relapsing.

After Shepard, who has been sober for 16 years, relapsed with painkillers over the summer, Bell says he gave her "full privilege" to hold him accountable.

"'You can drug-test me whenever you want. I'm going to buy some tests. I'm going to have them in the house. If you ever feel nervous, I want you to have access to this and I'll do it, no questions asked,'" Bell recalled Shepard telling her.

According to the "Good Place" star, Shepard wanted her to hold him accountable with the knowledge that he could be drug tested at any time.

Bell said her response was: "Maybe, some day. Why not?"

The actress, speaking from the perspective of someone who's married to a person with substance abuse, had nothing but praise for Shepard, who's been open about his battles with addiction and recovery.

"He's just good at trying, and that's all you can ask of anyone. No one's perfect," Bell said. "He's proven to me that he is committed to evolving and he loves personal growth."

Shephard first opened up about his relapse in September.

During an episode of his "Armchair Expert" podcast, Shepard said that after he had surgery for four broken ribs he sustained in a motorcycle accident in August, he was prescribed the painkiller Vicodin.

Shepard said on the podcast that he was on Vicodin "all day" for eight weeks after he was prescribed the prescription opioid, and later became addicted to the pills.

And in October, Bell explained her decision to "stand by" Shepard during his relapse on an episode of "The Ellen DeGeneres" show.

"I mean look, you know, everybody's up against their own demons, sometimes it's anxiety and depression, sometimes it's substance abuse," she said at the time.

Bell said she was grateful that Shepard was willing to open up about his relapse and ask for help.

"He was like, 'I don't want to risk this family and I did. So let's put new things in place to make sure it doesn't happen again,'" she said. "We're going back to therapy and I just love that he's addicted to growth. I will continue to stand by him because he's very, very worth it."