Among all types of depression manic depressive disorder or bipolar disorder is by far the least common. Nonetheless, according to recent studies and depending on the interpretation of the results of these studies about 1.3 to 6.4 percent of the population can be classified as having manic depressive disorder. This type of depression is characterized by mood swings between severe emotional lows (the depressive state) and highs (the manic state. In general manic depressive disorder is categorized as either Bipolar Type I or Bipolar Type II – the former defined by mania in its extreme form, the latter characterized by a less extreme expression of mania called hypo-mania.

The manic phases of manic depressive disorder are defined by a dramatic increase in energy leading to over-activity and over-confidence. The patient is also commonly over-talkative with a high speech-rate. The attention span is drastically lowered as is the ability to think rationally and to behave properly in social settings. This in turn leads to the affected person devising and pursuing unrealistic and oftentimes dangerous ideas, as well as to the unintentional creation of embarrassing situations in public. If left untreated mania can develop into a psychotic state. The hypo-mania characteristic for Bipolar Type II is less destructive than full-blown mania insofar as the symptoms are much weaker and usually last for a shorter period of time. The hypo-manic state can even lead to creative outbursts and, at least temporarily, to unusually high innovative problem solving skills.

The depressive phases of manic depressive disorder are in no way different than the depressive phases of other kinds of depression. The patient experiences prolonged phases of sadness, often without a cause, and a loss of energy leading to lethargy. He is indifferent and pessimistic; feels guilty and worthless; shows a loss of appetite and a change in sleep patterns – with insomnia being very common; is indecisive and unable to concentrate; experiences anxiety, irritability and anger. Furthermore, the patient may have recurring thoughts of death or suicide.

Sometimes manic depressive disorder patients experience a mixed state where certain aspects of the manic and the depressive state occur next to each other. For example it is possible that a patient experiences insomnia, paranoia, anxiety and suicidal thoughts as well as agitation, aggressiveness and hyperactivity. Mixed episodes of manic depressive disorder often are the most destructive mental state leading to self-mutilation, suicidal activities and substance abuse if untreated.

While some sufferers of manic depressive disorder experience only a few manic and depressive episodes during their lifetime the opposite is true for many other cases of this type of depression. Rapid cycling of mania and depression is hard to control and has a worse prognosis than the other types of manic depressive disorder. Interestingly the use of antidepressants can have a negative effect on patients experiencing rapid cycles or can even induce the rapid cycling state.

Concluding it has to be said that manic depressive disorder is a serious condition and arguably the worst of all types of depression. Probably to a large extent genetically pre-determined it cannot be healed. However, the condition can be alleviated and controlled by proper medicinal management and anyone suffering from manic depressive disorder is well-advised to seek medical help as soon as possible.