Major depression is characterised by a persistent low mood and loss of interest and pleasure. These symptoms are often accompanied by loss of appetite, insomnia, fatigue, poor concentration, inappropriate guilty feelings and even suicide. Depression was the third leading cause of disease burden among all diseases experienced by humankind in 2002. Antidepressants are used in treatment for major depression. They are the mainstay of treatment. Among them, mirtazapine is known to have a unique pharmacological profile and thus is supposed to differ in its efficacy and adverse effects profile in comparison with other antidepressants.