Erection problems are often caused by a combination of physical and psychological factors. The following causes are possible:
When older, it takes longer before the penis gets stiff and the man needs to be sexually stimulated for longer.
Anomalies in the vessels, for example due to heart and vascular diseases like arteriosclerosis and high blood pressure.
Surgery of the prostate.
Diseases and medication for heart and vascular diseases, diabetes
mellitus, multiple sclerosis and Parkinson's disease can be a cause.
Medicines for depression and high blood pressure may cause erection
problems (see also other question).
Smoking, drugs and alcohol dependence.
Anomalies of the penis.
It is important to know whether the body functions well. When an erection is possible: in the morning, while sleeping or when masturbating then physical problems can be excluded.
Erection problems are often a symptom of some other illness. Thus, if a man starts having erection problems, he should always get a general medical examination.