Before smoking two cigarettes on TV, Sean Penn admitted to host Stephen Colbert that he took a sedative ahead of the interview

Sean Penn made a memorable late-night appearance on Monday night.

The actor smoked not one, but two cigarettes during his Late Show with Stephen Colbert interview, and admitted to host Stephen Colbert that he took a sedative before. “I’m doing well. You’ve inherited a little of the Ambien I had to take to get to sleep after a red-eye last night,” Penn said at the start of his sit-down.

“So in other words, you’re still a little bit on the Ambien train right now?” Colbert asked before the two-time Oscar winner responded, “A little bit,” as he proceeded to light a cigarette shortly after.

Fans and viewers quickly took notice of Penn’s smoking on TV and shared their reactions on Twitter with many expressing bewilderment.

“Sean Penn is looking a little disheveled while #chainsmoking on #colbert,” one user tweeted.

Later in the interview, Colbert asked Penn to consider quitting cigarettes.

“Please don’t smoke anymore. I don’t mind. My parents smoked when I was a child so it gives me happy memories to smell cigarette smoke but you know we want you to be around for a long time and those things are bad for you,” the late-night host said.

“Job security for oncologists,” joked the Bob Honey Who Just Do Stuff author.

RELATED VIDEO: Sean Penn Says Most People at His Haiti Galas Are Stargazing and ‘Not Giving Anything’

The second guest of the night, Roseanne‘s Sara Gilbert, also reacted to Penn’s smoking, telling Colbert, “Wow, I just want to say, Sean Penn makes me look energetic.”

Sean Penn and Stephen Colbert
| Credit: CBS

Though his smoking garnered attention on social media, another interview moment was much-talked-about — this time in a more positive light.

Penn praised the students and survivors of the Feb. 14 shooting at Marjory Stoneman Douglas High School who organized the March for Our Lives protest in Washington D.C. on Saturday.

“Within days of that not only are they stating their case with incredible sobriety and articulate words but in such an inclusionary way. You feel like there are reasonable people who have been on the other side of this conversation who will listen to these kids,” he told Colbert, later nodding when asked if the students “give him hope.”

Bob Honey Who Just Do Stuff is available March 27.