Hollywood actress Gwyneth Paltrow has revealed that a bad experience with Botox left her looking "like Joan Rivers".

The 40-year-old Iron Man 3 star makes the frank admission in the May issue of Harper's Bazaar.

Paltrow, who has two children with Coldplay singer Chris Martin, said that raising a family while enjoying a successful acting career was difficult.

She admitted that although her healthy lifestyle has helped her maintain her youthful appearance, she would not rule out plastic surgery when she gets older.

"I would be scared to go under the knife but talk to me when I'm 50. I'll try anything," she said.

"Except I won't do Botox again because I looked crazy. I looked like Joan Rivers."

Cigarettes and tofu

As a fitness and health fanatic it comes as no surprise that she runs lifestyle blog Goop, where she shares her tips with fans.

"I use organic [beauty] products, but I get lasers. It's what makes life interesting, finding the balance between cigarettes and tofu," Paltrow told the publication

"In terms of beauty regimes, I've probably tried everything," she said.

The actress, who found fame in the 1995 thriller Se7vn and became known for her roles in Sliding Doors, Contagion and The Talented Mr Ripley, revealed that she was keen to step out of her comfort zone and try an "outrageous girl comedy".

"You can call me a lot of things, but you can't call me complacent," she said.

The May issue of Harper's Bazaar is out on 23 April.