Mandarin oil is also useful for treating acne, oily skin, and spots. It is supposed to help ease problems such as fluid retention and obesity as well. The oil, diluted around 1-2% in a carrier oil, is massaged gently on a child's tummy to relieve a tummy ache. A few drops in the bath calms hyperactive children. Used in an oil burner, it dispels depression and relieves anxiety.