Robin Wright believes she "has to" have Botox injections.

Robin Wright

Robin Wright

The 'House of Cards' actress thinks the muscle-freezing treatments are an essential part of looking good on television, but she won't overdo the dosage as she doesn't want to risk rendering her features immobile.

She said: "Oh my God, of course, you have to [have Botox].

"That's why it's called a sprinkle. I think most women do 10 units, but that freezes the face and you can't move it.

"This is just one unit and it's sprinkled here and there to take the edge off."

The 49-year-old actress - who recently split from Ben Foster after four years of dating - insists she isn't worried about turning 50 because she is so content with her life.

She told ES magazine: "They're just numbers. And you know what? When you step back from it, it's like: bring it on. I've never been happier and more sound -- just... at ease.

"And that's the greatest birthday gift -- the greatest bit about getting old. You're less worried, you're less frenetic about things."

Though Robin - who has children Dylan, 24, and Hopper, 21, with ex-husband Sean Penn - always tries to be kind, she admits that she can also be a "b***h".

She said: "I'm a b***h sometimes. We're all that sometimes. But I like kindness and I like to keep reminding myself of that as a goal."