I was reading Prevention magazine the other day, and came across a short news article dealing with a study that was conducted on help for depression.
It was found that citrus essential oil (lemon or orange)had a positive effect in alleviating depression. The subjects sniffed the essential oil once each hour and found that this type of aromatherapy enabled them to reduce the amount of depression they were feeling.
Obviously, this is NOT a replacement for medication or therapy, but it could be a helpful addition. The caution was listed that the essential oil should not be used directly on the skin, nor should it be taken internally.
You should be able to get this either online through a site such as drugstore.com or vitaminshoppe.com or at a health food store. Be sure to get the natural vs synthetic essential oil. The natural is more expensive, but the synthetic, chemical oil usually doesn't have the same effect.
Hope this helps.