Mirtazapine is not considered to have a risk of many of the side effects often associated with other antidepressants like the SSRIs, and may actually improve certain ones when taken in conjunction with them.[1][2] (Those adverse effects include decreased appetite, weight loss, insomnia, nausea and vomiting, diarrhoea, urinary retention, increased body temperature, excessive sweating, pupil dilation and sexual dysfunction.[8][44])