Particularly, the fall of PRL levels below the lower range of normality during medical treatment with dopamine agonists appears to be associated with impaired gluco-insulinemic and lipid profile, and to promote weight gain, visceral obesity, insulin-resistance, diabetes mellitus, dyslipidemia, chronic inflammation, and sexual dysfunction, thus leading to the increase in overall cardiovascular risk. The gene discussed is PRL; the disease is metabolic syndrome.