Rimonabant, antagonist at CB1, has long been used as an anti-obesity drug able to induce weight loss, improve blood lipid parameters and increase the adiponectin level in obese patients [67], but it had severe side effects including depression, anxiety, nausea and dizziness probably due to the blockade of central CB1. This evidence concerns the gene CNR1 and obesity due to melanocortin 4 receptor deficiency.