WE'VE all seen men going through mid-life crises on the big screen - Kevin Spacey in American Beauty immediately springs to mind. But in real life, many men who have symptoms of depression, irritability and tiredness just put it all down to a mid-life crisis, when, in fact, they are going through the male menopause.

A lot of them, including those who suffer loss of libido, wouldn't consider seeking medical help, and doctors themselves also often fail to recognise the male menopause as a real medical condition.

Physical symptoms may include wrinkles and other signs of ageing, aches and pains, particularly in the hands and feet, sweating, hot flushes and failing sexual performance.

While the benefits of hormone replacement therapy for women have been well documented, little acknowledgement has been given to the help available to menopausal men. Yet there are treatments to stop the symptoms that affect many men in middle age or earlier, according to Dr Malcolm Carruthers, a leading pioneer in the male menopause, or the "andropause", as it is known in Europe.

Dr Carruthers believes the male menopause affects 50 per cent of men in their 50s and believes that, like women, they need to take HRT, or in their case TRT, Testosterone Replacement Therapy.

There is, of course, much more to ageing than hormonal decline, but Carruthers says it is possible to prolong a youthful balance of hormones by supplementation of testosterone in men.

''It shares many of the benefits of oestrogen therapy, both in the treatment of symptoms of menopause and in all round mental and physical health maintenance,'' he says in his new book, The Testosterone Revolution.

TRT often proves the key to recovery and puts men in a much more positive frame of mind to undertake the other necessary steps, such as managing stress, drinking less, losing weight and exercising, he says.

Detailed health history and lifestyle assessments will have to be made as well as extensive physical checks before TRT can be prescribed.

Triggers for a reduction in testosterone include stress, weight gain, excess alcohol and lack of exercise. Other factors such as vasectomy and environmental pollution can also have an effect on a man's fertility and virility, says Dr Carruthers.

Once a hormone profile has been built up, a second session is needed with a doctor to go over the results and go through the treatment programme.

''This is usually not just getting testosterone, but also involves active input on your part, modifying your lifestyle in a variety of ways, reducing weight and alcohol intake, changing to boxer shorts and adopting strategies to cope with stress, if necessary,'' Carruthers explains.

TRT can be given in the form of injections, pills and pellets and through the skin as creams and patches. Around 60 per cent of patients take the pills, while more than 50 per cent have injections and ten per cent use body patches, with less than five per cent having pellet implants.

Testosterone is made synthetically from cholesterol, the same raw material the body uses to manufacture it. The cost is around two to three times that of female HRT.

He notes that both oestrogen and testosterone can be regarded as anabolic or body building steroids. Some of the resistance to TRT has arisen over the last two generations of doctors because of the abuse of anabolic steroids by athletes and body-builders, says Dr Carruthers.

But he points out: ''As the amounts taken by abusers are often ten to 20 times the therapeutic doses, these illicit and thoroughly undesirable experiments appear to have proved that most anabolic steroids have a considerable margin of safety, for men at least.''

Just as most recent studies of HRT have shown little, if any, increase in the incidence of breast cancer in up to 10 years' treatment with oestrogens, 50 years of TRT treatment with implants and 30 years of TRT injections do not show any rising incidence of prostate cancer. Dr Carruthers says: ''TRT for men is as safe, if not safer, than HRT for women.''

However, the image of TRT was tarnished in 1935 when the first oral form was introduced, methyl testosterone, which had dangerous side effects including damage to the liver cells, resulting in cysts and even cancer.

Dr Carruthers observes: ''Even though we now have much safer medications, this one can be obtained over the counter, without prescription, in many parts of the Far East and is still the only oral form of testosterone available in the United States.'' He says there are two much safer oral medications available in Britain - testosterone undecanoate and mesterolone.

Dr Carruthers believes that in the future TRT for men will sit alongside HRT for women as an integral part of preventive medicine in this century.

Not everyone shares Dr Carruthers faith in testosterone, however.

Dr Anand, an unashamedly unconventional GP in Newcastle, believes that flagging testosterone in older men is no bad thing.

"As a species, humans are already over-sexualised. I think it would be a dangerous thing if you had 50 per cent of men taking testosterone," says Dr Anand. "A small number of men can benefit from this treatment but I have real concerns about making it more widely available."

"Sex is already too much on our minds. We should probably go around giving men testosterone-depressing drugs to calm them down. After all, men are supposed to think about sex every seven seconds."

Dr Anand, who is based at the Elmfield practice in Gosforth, says extra testosterone would probably fuel male frustration. "This is not going to help society. Men need to be more feminine, more soft-hearted and kind," he adds.

To Dr Anand, the sexy images of women sold to us by films and television are the other side of the coin to the kind of exploitation of women we have seen in Afghanistan.

"I think there is not such a great difference between Hollywood and the Taliban," he says. "One exploits women and the other covers them up. It's part of the same process."

* The Testosterone Revolution by Dr Malcolm Carruthers (Thorsons, £14.99)