When you are depressive in bipolar disorder, the symptoms are hardly any different from those of regular depression.
You get the same painful sadness, the negative thinking, and the indifference to things that used to make you happy.
And yes, you get the suicidal feelings too.
Work, activities and people tend to turn you off; you lose sleep and appetite; you get the feelings of worthlessness, helplessness and pessimism as added feelings; and then comes the delusions and false sensory perceptions that look like genuine psychosis.
You see, if you treated a bipolar disorder patient only for the manic symptoms, you could set of a very severe depressive episode; and if you treated only for the depression, you could trigger some major mania that may not be very easy to come out of.
Worse than either of these situations, you could cause a rapid-cycling manic-depression that could permanently fracture the mind of the patient.
Yep, all of these forms of depression have a lot in common and they are closely related.
They all leave you dejected and with suicidal tendencies, to mention but a few.
You don't want to be too rash with the diagnosis so that you don't end up catching the wrong condition.
You want to take your time observing so that if it is bipolar disorder, it can be properly diagnosed, and the patient who is suffering from it can be accorded the best treatment you can get your hands on.
Knowledge of the peculiar signs of the depressive state of bipolar disorder is very important to distinguish them from those of clinical depression.
Also, it will help in the provision of the right treatment for the condition.