Dax Shepard is opening up about his road to sobriety.

The 45-year-old actor revealed in the latest episode of his podcast, Armchair Expert, that he relapsed shortly after celebrating 16 years of sobriety with wife Kristen Bell.

Dax’s first slip-up took place eight years ago while visiting his then-sick father, a cancer patient to whom the actor offered Percocet to ease his pain. The actor said he took double what his Vicoden prescription was at the time while bonding with his dad before he died.

“You know, we had so little in common and so much f–king friction,” he recalled. “But the number one thing we had in common was we were both f–king addicts and we had never used anything together. And we sat there stoned and looked at the lake. And in that moment, I felt elation and I was just happy.”

Dax later admitted to Kristen that he had relapsed.

“That was eight years ago,” he continued, later adding, “I’ve now had this experience where I did that, I felt bad, but there wasn’t any fallout from it. It was like, I felt bad, I said I felt bad, and then I did just move on and it was fine.”

Dax has battled medicating himself for pain due to several motorcycle injuries over the years. But he admits to struggling between medicating real pain and feeding into his addiction.

“I go ride a lot,” he said. “After I ride sometimes on the track, I feel I’m entitled to take two Vicodin at the end of the day because I am in pain. That again doesn’t feel that crazy.”

However, six months ago he began to notice that he was upping his pill intake.

“For the last eight weeks maybe, I don’t know … I’m on them all day. I’m allowed to be on them at some dosage because I have a prescription. And then I’m also augmenting that,” he shared. “And then all the prescriptions run out and I’m now just taking 30 mil Oxys that I’ve bought whenever I decide I can do [it].”

The actor then added that he started hitting bottom when he hid the habit from Kristen and when he began lying to his podcast co-host, Monica Padman.

“And I’m lying to other people and I know I have to quit,” he acknowledged. “But my tolerance is going up so quickly that I’m now in a situation where I’m taking, you know, eight 30s a day, and I know that’s an amount that’s going to result in a pretty bad withdrawal. And I start getting really scared, and I’m starting to feel really lonely. And I just have this enormous secret.”

“I now start getting pretty visibly detoxy and withdrawly,” he added. “And I lie and start saying I’m having an arthritis flare-up.”

Dax later apologized to Kristen and Monica, saying that he is afraid of relapsing again.

“My fear was that if I have one day, I’m going to drink and I’m going to do coke,” he said. “I haven’t drank a beer in 16 years and I haven’t snorted a line in 16 years. And if I have one day, then I might as well f–king have what I really want and then start over. And my fear of that is if I do that, it may take me three years to get that back in the cage and I may die.”

We love you, Dax. The first step is always knowing there’s a problem. Thank you for being so honest.

Listen to the full episode HERE.