'It was HRT or Holloway'

She's been voicing the thoughts of grumpy old women for a decade, both on screen and on stage, but now Jenny Eclair is turning her attention to a subject close to her heart - middle age. About to embark on a major UK tour with her new show, How To Be A Middle Aged Woman (Without Going Insane), she is pictured on the flyer in an unflattering bra and knickers, no airbrush in sight.

Eclair, 55, writes about what she knows. And her latest tour is no exception. "It's about the fury of middle age and what you can do about it. I had to go on HRT because my anger issues became insane. I was dangerous. I was very close to killing something. It was HRT or Holloway prison for me. I was angry about everything. Geof, my partner, loves the HRT. He really panics if I tell him I'm a bit low. I'm now the nicest I've ever been, and the fattest. I've bloomed and mellowed.

"I also get cross about the underestimation and the patronising of middle-aged women. When Kate Bush came back and did those gigs, everybody was very excited, but underneath it all they were thinking, She's going to make a complete tit of herself, run up that hill, fall over, cry and run off stage'. And the fact that they're going to have a woman of 50 having sex with James Bond has caused a big furore. It's Monica Bellucci, it's not like it's a dinner lady with a bandage around her ankle," she adds, on a roll.

The tour runs until next spring, although she'll have some time off at Christmas, so is hoping to slot in a panto. "Deep down, I'm greedy, lazy, selfish and not very nice, so I have to distract myself with quite a lot of work. I crave a nice, cushy afternoon quiz show. I've never had that."

Indeed, in the last decade Eclair has appeared more on stage than on TV, and has been a prolific writer. "Telly's not interested," she says with a shrug. "When the Grumpy series finished, they decided they were going to take the 'old' out of the title and would just do a series of grumpy women and grumpy men and use much younger people, and of course, it didn't work. So they killed it off on the telly. But the brand is really strong on the road, because there's always an army of middle-aged furious women who like to come together and be in the same room and recognise themselves and laugh at it."

She lives in London with her daughter Pheobe, 26, a playwright, and partner of 33 years Geof Powell. So what's the secret of their happy union?

"We have no secrets but there are rules. Rules for him: if in doubt, tell her she looks like she's lost weight; remember the names of her three best friends, do not refer to them as Shorty, Fatty and The Fit One." And rules for her? "There are no rules," she says flatly.

She's guested on Countdown, QI and Loose Women and done the reality show circuit, from I'm A Celebrity... to Celebrity MasterChef and Splash!

"They're like panto. It's an opportunity to make a chunk of money - more than I get for writing a book. But TV is not something I rely on. I'd love to do more telly but it doesn't really present itself that often. I think I'm quite difficult to harness on television. I'm not very well groomed. I look a bit peculiar. Everyone tends to be a little bit neater and a bit more well behaved. I'd love to do a sitcom. Telly and I have unfinished business. Our relationship hasn't been bad but I don't think I've ever found my niche there. It's a tricky beast."

Eclair has now written four novels, as well as a string of stage shows. Her latest book, Moving, centres on a woman who is selling the house she has lived in for more than 50 years, and the memories it stirs as she goes through each room with the estate agent, taking her back to her old life as a young mother, her first husband and their twins, then her second marriage to a very different man with a son, who is difficult, to say the least.

"Houses have always been very important, because I moved a lot as a child and my partner does up houses," she explains. "Some of my friends have started to think about downsizing and you suddenly become aware of how much your house contains."

Eclair was one of the first stand-up females. "French and Saunders were doing double act stuff. There was only Victoria Wood, but she was doing stuff that was very different from what I wanted to do, because mine was much ruder and much madder at the beginning, which is why lots of people didn't like it."

Like the fictional drama student in her latest novel, she's suffered stage fright. "I only got stage fright later on in my career, which came with anxiety. It happened a couple of times. "I had a wave of it once at the Edinburgh Festival in 2000, and once in Australia when I was on stage in Sydney in Grumpy Old Women. It was a massive theatre and I didn't think the audience got it in the same way that British audience did.

"I got this absolutely huge wave of fear. I thought I was going to be sick, I thought I was going to faint, I had to hold on to furniture. It was paranoia, symptoms of anxiety. Anybody who has a panic attack can tell you that you just feel light-headed and that you're going to be sick and faint.

"I always had to use valium. I'd do half a tab - I love a bit of valium - but I don't do it now. I literally manage to get five valium to last about five years. "I have high expectations of myself, not wanting to drop the ball, not wanting to fail. I think most performers have an anxiety button they can press now and again."

• Moving by Jenny Eclair (Sphere, £13.99). For details of her solo tour, which is visiting Harrogate, Durham, Newcastle, Stockton and Barnard Castle, visit www.jennyeclair.com