The process of an erection involves the nervous system. For this reason, nerve disorders can lead to erection problems and, ultimately, erectile dysfunction (impotence).

Common nerve disorders which can cause erectile dysfunction include diabetes, multiple sclerosis and spinal cord injuries.

Fortunately, all general erectile dysfunction treatments are also appropriate for those erectile dysfunction sufferers with nerve disorders – although, obviously, the best treatment for any individual is dependent on their particular circumstances.

ED, sex and nerve disorders
The nervous system is spread throughout the body and consists of two main sub-systems. The ‘somatic’ system is the network of nerves that go to our muscles and which also receive sensations such as touch, hearing, sight and smell. This is the part of the nervous system over which we largely have control – for example, we can command a muscle to move at will.

The other main part is the ‘autonomic’ nervous system. These are the nerves which are involved in regulating body temperature, pulse, blood pressure, digestion and so on, and in the main do so in the background, without need for direct orders from the brain.

The process of an erection involves both parts of the nervous system. For example, the somatic system is involved in touch and sensation during intercourse whereas the autonomic system controls the reflexes that open up the blood vessels within the penis.

ED and nervous system disorders
Diabetes is the commonest condition that can affect the nerves and lead to ED. Multiple sclerosis and spinal cord injury are the two other main ones.

Multiple sclerosis
Multiple sclerosis (MS) is a condition in which problems arise with the ‘insulation’ that separates the individual nerve fibres within the brain and spinal cord. The speed with which MS develops and the extent of its effect can vary considerably between different people. Some can become quite disabled over just a few years whereas other people with MS have minimal effects that show little or no worsening over decades. It is generally impossible to predict in advance how any individual person’s MS will behave in the long term.

MS can affect any part of the nervous system. One of the potential consequences for an affected man is erectile dysfunction, and both men and women with MS can also suffer from difficulty in achieving orgasm. Exactly how many men with MS also have ED is difficult to say because relatively few good studies have been made in this area. A survey by Ghezzi and colleagues in 1995 indicated that 44 per cent of affected men had some sexual difficulty and 38 per cent had total ED.

Spinal cord injury
Spinal cord injury, like MS, can vary tremendously in its effects. If, for example, the spinal cord has been crushed but not torn, then good recovery might occur even after prolonged paralysis. However, when nerves are cut they very rarely regain their function. When a spinal cord injury in a man leads to paralysis and loss of sensation of the lower half of the body it is inevitable that ED will also occur.

Treatment of erectile dysfunction in nerve disorders
All of the treatments available for ED in general are also appropriate for men with a nerve disorder, although the most suitable treatment for an individual depends on his particular circumstances. For example, an affected man might have difficulty obtaining an erection through fantasising about sex yet might be able to do so by using a penis vibrator or vigorous massage from his partner. This is because the nerves connecting the penis to the spinal cord may well be intact and therefore the part of the erection reflex that depends on local stimulation may be intact and just needs to be reinforced.

Undoubtedly, the main advance in this, as with other forms of ED, has been oral treatments, which are now the first-line treatment, with other methods generally used if these fail.