Behavioral symptoms are known to be a prominent feature of Gilles de la Tourette syndrome (GTS), although little is known about irritability in this patient population. This study investigated the clinical correlates of irritability symptoms in 101 adult patients with GTS. We found that patients with more severe tics (especially vocal tics) report higher levels of irritability (r=0.37, p <0.001) Furthermore, irritability levels appear to be higher in those patients with comorbid attention-deficit and hyperactivity disorder, in whom poor impulse control is common. These findings prompt further research focusing on the possible link between irritability and impulse dyscontrol in GTS.