It's a known fact that professionals -- physicians included -- are not an exception from the mental illnesses and addictions that individuals in the general population experience.
A recent article on Psychology Today's website reports that the suicide rate among male physicians is 1.4 times higher than males in the general population, and that the suicide rate among female physicians is 2.2 times higher than the women in the general population.
The article describes research which compared information on physicians who died by suicide with individuals in the general population who died by suicide during the same 5-year time period.
Doctors may suffer from alcohol or substance abuse disorders, depression, and certainly a large amount of work-related stress, according to the article. Also, because of the type of work they do, they might be aware that they are dealing with a mental health condition -- such as bipolar disorder or depression -- but do not seek help for fear that it could interfere with their career.
According to the article,
...antidepressant use was not found to be higher among physicians. Rather, use of antipsychotics, benzodiazepines (drugs such as diazepam, alprazolam, and lorazepam), and barbiturates was higher. Barbiturates are not commonly used in clinical practice these days other than for epilepsy and anesthesia, and thus these agents might have been used to overdose.