Psychosis is sometimes believed to be an opposite of depression. It is not happiness, but it is sometimes marked by an excessive level of energy, where depression is known for slowness. Medications used to treat psychosis sometimes create depression, and that could be related to why they work.
In some cases a person's depression is so severe that it creates a "fight or flight" response, and triggers psychosis. When excessively depressed, a person's nervous system starts to regard this as a threat, and this triggers an extreme reaction that opposes the depression, namely a fight or flight reaction and also psychosis.
On the other hand, sometimes a person's psychosis is negative enough (consists of too many negative thoughts) that it can produce a type of depression. This is one reason why a drug called "abilify" was recently marketed as useful to combat depression. Abilify is an antipsychotic drug, and by cutting down on aberrant, negative thoughts, it may sometimes relieve depression. This is a different approach to dealing with depression than strictly using an antidepressant. Depression is sometimes caused by a lack of neurotransmitters, or sometimes, it is caused by an excess of them.
For psychotically depressed people, either psychosis or depression can come first and activate the other. Either way, a person is dealing with something that is hard to treat. Their brain is producing symptoms that are at opposite ends of the scale.
Psychotic depression is miserable to experience. It is a very bad thing that seems to often happen to good people. You may feel hyper and agitated and yet the outlook is gloomy, and everything seems awful. In some instances, you have a lot of energy accompanied by negative thoughts. Yet this high energy doesn't translate into doing work or getting anything useful accomplished-you feel restless like you can't settle down, but doing work is out of the question. If this weren't so, I would say that there was something positive about psychotic depression. The only positive thing I can list about this particular ailment is that it is a good thing once you get out of it.
(Obsessive compulsive people, a group I don't know much about, seem to be the ones that often get a lot of work done due to their symptoms. I have met two or three small business owners, who are workaholics, who told me that they were obsessive-compulsive.)
When one comes out of a phase of psychotic depression, one feels more relaxed and at the same time, there is more usable energy to get things done. The good thing about depression is that sooner or later, it usually lets up. The good thing about psychosis is that with treatment, it can subside.
People with psychotic depression are more prone to suicide than are some others. This is because it contains misery along with high energy. It means that you are miserable enough (and erroneously feel hopeless enough) to make suicide plans, and you have enough energy to carry them out.
At certain points in my past, I have experienced psychosis and depression at the same time. And I do know, firsthand, that it is an awful type of suffering, one that can't be easily solved.
If you think you or someone you know has psychotic depression, get that person some help. A doctor can prescribe an antidepressant and an antipsychotic to treat it, or may just prescribe one or the other. Regardless, there is no reason to suffer unnecessarily.
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