Last week, in his first interview since seeking treatment for addictions to drugs and alcohol, Panic! at the Disco drummer Spencer Smith said he couldn't wait to return to the road with his band ... but admitted that he was "nervous" about the prospect of staying clean while on tour.

"Coming into it I feel really positive about where I'm at, but I can't know every situation I'm going to be in on tour. I'm going to be in hotel rooms where there's alcohol readily available," he said. "But I'm lucky to be in a band that isn't Guns N' Roses or something; it's a great thing to not have to feel like I'm having to alter everybody else's life so that I can fit in. That's something I didn't want to do."

Smith added that, while his bandmates were "very accepting" of his newfound sobriety, there were no plans to ban alcohol backstage — "There is probably going to be some limited amount," he said — but, ultimately, that didn't matter. After all, his recovery had provided him with a clarity and a sense of purpose he hasn't had in years.

"It feels like what I'm doing is right, and what we're doing is right," he said. "It hasn't been that way since the first album, and I can't wait to keep going from here."

Sadly, on Wednesday, after playing a handful of shows with Panic!, Smith has left the tour. Frontman Brendon Urie made the announcement in a message on the band's official site, and though he didn't get into specifics, his post made it very clear that Smith just wasn't ready for life on the road.

"It's become evident that Spencer still needs more time to take care of himself. I can't expect him to be fighting addiction one minute and be fully immersed in a national tour the next," Urie wrote. "With that said, the tour will continue without Spencer while he is away getting the help he needs. Thank you all for your support and kind words."

Panic! are still booked to perform on Friday night in Jacksonville, Florida, though it's not clear who will replace Smith behind the kit. A spokesperson for Panic's label, Fueled By Ramen, did not respond to MTV News' request for comment on the matter by press time. They're also set to join Fall Out Boy on the Save Rock And Roll tour next month.

In his message, Urie made mention of Panic's rather tumultuous past, which has included the ouster of founding bassist Brent Wilson in 2006 and the exit of guitarist/singer Ryan Ross and Wilson's replacement, Jon Walker, in 2009. With Smith's departure, Urie is now the only original member remaining in the band.