Nocturnal erections are markedly diminished and this manifests as a loss of erections on waking. Psychogenic impotence is more likely to have an abrupt onset. The impotence is often inconsistent, occurring only in certain situations. Nevertheless, organic impotence usually invokes a secondary psychological overlay which may complicate evaluation of the aetiology. This underlines the need for a careful, unhurried approach and empathy during history taking.
Androgen deficiency causes more loss of libido than erectile dysfunction.
It is unusual for men complaining of impotence to have androgen deficiency as a cause of their sexual dysfunction. This is in contrast to the low sexual activity of androgen-deficient men which often causes them little concern. Altered peripheral pulses and neurological reflexes in the legs can be evidence of vascular or neurological disorders. Investigation Few investigations of erectile dysfunction lead to specific interventions, so extensive testing cannot be justified in routine practice. Specific correctable underlying causes such as androgen deficiency or pituitary tumour should be sought, even though they are rare.