Experiments with men and women showed that those who were allowed to express their anger aggressively became more aggressive afterwards, compared to subjects who were encouraged to calm down after becoming angry. Evidence also shows that anger, like other strong emotions such as shock, can trigger heart attacks. One study of heart attack survivors showed that in the two-hour period after someone experiences intense anger, heart attack risk doubles. In a healthy person, this may not amount to much, but in someone already with heart disease, this can be very dangerous. According to psychologist Anne Alonso, clinical professor of psychiatry at Harvard Medical School, venting may cover up something deeper that's going on.
Anger is often a defense against feelings of helplessness and depression.
So when you encourage the defense, you put a greater distance between the real problem and the patient's ability to deal with it. No one is asking you to be a doormat. But if someone makes you angry, tell that person in a calm way instead of lashing out at him first. If you need to, count to 100. The main thing is to step back from an angry situation and cool off before you respond.