Just like women, men experience a decline in sex hormone levels beginning in their 40s. However, the decline in men is gradual and proceeds over a number of years. As a result, the onset of symptoms may be subtle and ill-defined. Symptoms are varied and may include hot flashes, sweating, insomnia, nervousness, irritability, tiredness, loss of motivation, short-term memory problems, declining self-esteem, depression, decreased energy levels, diminished muscle strength, decline or loss of libido or sexual desire, poor erections, reduced orgasmic quality, reduced volume of semen, diminished muscle mass, hair loss, and abdominal obesity.
Other symptoms that have been related to AD include a reduction in high-density lipoprotein (HDL) cholesterol, an increase in total body fat, osteoporosis, and a reduction of the proportion of red cells in plasma. Erectile dysfunction or the inability to achieve and maintain an erection through the completion of the sex act is rarely linked to AD. If sexual desire exists but function does not, the problem does not stem from low testosterone levels and testosterone replacement is not indicated as a therapy. Other effective therapies apply.
As can be seen, many of these symptoms may emanate from other disorders or they may be a normal aspects of getting older. For this reason, diagnosis of AD never rests on symptoms alone.