Clinical depression is caused by genetic factors, childhood experiences, adverse life events and physical illnesses.
Genetic factors: according to research, between 40-70% of all cases of clinical depression have a genetic cause. Most patients have been found to have a familial history of clinical depression. In other words, most patients have either a father or mother who was at least once clinically depressed
Childhood experiences: when a child is exposed to unpleasant experience such as loss of parents, bullying, child abuse, sexual abuse, peer rejection, display of antisocial traits by parents, chances are very bright that such a child will be clinically depressed for life if not attended to. Many cases of persistent depression and suicide were due to nasty childhood experiences.
Adverse life events: unpleasant occurrences such as failure in examinations, bereavement, loss of a job or source of income, divorce, change of environment to one of alien lifestyle, stress, retirement, marital problems, menopause, pregnancy, social rejection or isolation, and childbirth are common causes of clinical depression.
Physical illnesses: hypogonadism, Addison’s disease, Lyme disease, and myasthenia gravis, are all diseases, which lead cause clinical depression.
In addition to the aforementioned, clinical depression may also be a side effect of medications. An example of such medications is alpha-methyldopamine, or Aldomet, which is used to treat hypertension. It has been observed that most hypertensive patients who were treated with this drug later suffered clinical depression. Other similarly complicated medications include Zovirax, an anti-herpes drug, Diazepam, and Disulfiram.
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