Depression is generally thought to result from biological, psychological and social factors. Therefore, the treatment for depression will ideally address all these issues. In practice it is often the case that medication is the only help available, meaning the underlying causes go untouched.
As medication is the most common form of treatment it makes sense to look at this first. Assuming the first attempt at medication works it can take up to eight weeks before any therapeutic effect is felt. Some people may need to try different antidepressants until they finally discover one that has a positive effect. The most commonly prescribed medications are from a class called selective serotonin re-uptake inhibitors (SSRIs). The action of the medication is to retain serotonin within the brain which has the effect of lifting mood in most people.
The second main approach to the treatment of depression is psychotherapy. There are a variety of therapy options available but cognitive-behavioral therapy is the most popular. It is effective, safe and well researched. The client takes an active approach in the treatment sessions as to how they can change the way they feel by modifying their own internal thought processes.
When depression hits hard it can lead to suicidal thoughts or attempts at suicide. In such circumstances hospitalization is probably the best treatment option, preferably with the consent of the patient. I have seen patients so deeply depressed they have stopped eating and drinking and appear actively psychotic.
This leads me to my final example of treatment options which is the use of Electroconvulsive Therapy (ECT). ECT is essentially only used in the most severe cases of depression where conventional treatment has failed or cannot be applied owing to the severity of the condition. The patient is fully anesthetized after which a brief electrical pulse is sent into brain. This causes a seizure, which is thought to have the therapeutic effect. More information about ECT