Which could help with male impotence or libido?

A check up. Ed or libido problems can be due to physical causes (usually vascular insufficiency) there are many medical problems that may cause these problems which can be readily diagnosed by a urologist interested in sexual medicine. There are also psychological contributions to ed as well. Finally low testosterone may be the culprit here which is easily assessed by a blood test.
Get consultation. The issue you are asking about is often a symptom of depression or anxiety. It you often feel sad or nervous; if you are having sleep problems or appetite problems; if you are also having trouble with work, school or relationships, then see a psychiatrist for a consultation. If you don't have other symptoms, see a psychiatrist anyhow!