Two of the most popular dietary supplements used for insomnia are: 1  Melatonin, a hormone produced by the brain. You can also buy it as a supplement. 2  Valerian, an herbal sleep remedy. Valerian appears to be safe, and it may improve sleep when taken for a week or two.
The average spell of clinical depression, if left entirely untreated, will last around 8 months. During a depression, the sufferer will normally be convinced that it will never go away, but this is a classic feature of the way depression makes us think.
This question is more complicated than it sounds, as it depends how 'depression' is defined. Major depressive disorder, as described in dsm-iv, lasts at least 2 wks & sometimes up to several years. A very rough guideline is 6 mo if untreated. Other depressions are quick reactions lasting just hours or a few days, while depressive personality (usually mild) can be lifelong. All can be treated.