Amanda Seyfried believes Paramount owe her money for Mean Girls merchandise.

The 39-year-old actress - who played Karen Smith in the 2004 movie - loves the enduring popularity of the teen comedy but admitted she feels "a little resentful" because her fact appears on so many T-shirts and she doesn't get any royalties for the use of her likeness.

Asked if she has rewatched the film, she told Adam Brody for Variety's Actors on Actors series: "No. It's on often enough though. I love it. I really love seeing my face on people's T-shirts.

"I'm a little resentful because Paramount still owes me some money for the likeness. Every store sells Mean Girls T-shirts with our faces.

Amanda questioned if she missed out on extra revenue because she was young and "dumb" when she signed her contract for the film.

She said: "Don't I [get something from that]? Is it because I was 17 and dumb? Or is it..?' "

But Amanda is always grateful when she meets fans of the film.

She said: "Even the girl at TSA tells me it's her favourite movie. I'm like, 'Great! I had nothing to do with it, I was 17...'"

Meanwhile, the Mamma Mia star - who has two children with husband Thomas Sadoski - thinks she is "allergic" to marijuana, though she had some enjoyable times consuming the drug with Adam.

Reminiscing about visiting a beach when they filmed 'Jennifer's Body', she said: "I don't know if I could do pot again. I think I'm allergic to it. I had some bad experiences.

"But I remember that being the most peaceful. That was probably the last time. I might have also gotten stoned with you at your house that I now own.

"I think the only time I've enjoyed pot was with you, so thank you. You have an effect on people. Look at what's happening: You're in a hit show, and people are gasping, 'Adam Brody'."

The Nobody Wants This star quipped: "I don't think it's pot-related."

Amanda agreed: "No, it's just that you make people feel at ease."

Adam said: "I really appreciate that, I think because I'm pretty attuned to people's discomfort because I'm in touch with my own, so I don't think I'm a bad host in that way."