Everyone knows that women undergo menopause with age.

However, there is a less well-known male 'equivalent' of menopause: Andropause.

Literally translated from Greek, 'andropause' means to 'cease being a man'. Medically, this would indicate a loss of testicular function.

However, the word is more often taken to refer to Late-Onset Hypogonadism, which is a clinical and biochemical syndrome associated with advancing age and characterised by typical symptoms and deficiency in serum testosterone levels, said DrJames Lee, associate consultant, department of obstetrics and gynaecology, National University Hospital.

Unlike menopause in women - easily characterised by the cessation of menstrual periods that occurs around the age of 51 - andropause 'has no point of reference that can be easily recognised', said Dr Lee.

As such, the definition of the condition is not as clear-cut, although 'most experts would concur that it should be diagnosed by a combination of biochemical measurements (low testosterone) and validated signs and symptoms', said Dr Lee.

Also, andropause is not limited to a narrow age range like menopause and its effects can be experienced by men as young as their early 40s and as old as their 80s.

Due to the dropping testosterone levels that come with age, one of the most prominent indicators of andropause would be a decline in sexual function and the failure to maintain an erection.

However, Dr Lee stressed that there are many other symptoms of a decline in testosterone level.

'Testosterone influences the formation of red blood cells, bone calcium build up and mineralisation, fat breakdown, carbohydrate utilisation, liver function, muscle mass and prostate gland health,' he said.

Furthermore, the outward symptoms of lowered testosterone levels are different for elderly men. For them, a change in mood and cognitive functions - as reflected in anxiety, irritability, insomnia, memory loss and a decrease in mental sharpness and intellectual activity - have been linked to reduced testosterone levels, said DrLee.

If a clear diagnosis of andropause has been made and its effects are devastating, there are ways to treat its symptoms.

'Most men will benefit from androgen replacement therapy which, in Singapore, comes in the form of oral tablets or depot (slow-release) injections,' said DrLee.

There is also the traditional Chinese medicine approach to andropause which attributes it to the loss of 'qi' in the 'kidney organ system'. The system governs the integrity of the sexual organs and a person's overall well-being, said Dr Lee.

Hence, it is believed that andropause can be prevented by strengthening the kidney organ system by taking herbal brews or acupuncture.

This article was first published in Mind Your Body, The Straits Times on May 21, 2008.