Tolerability profile of clonidine in the treatment of adults with Tourette syndrome.

OBJECTIVE: Clonidine, an alpha-2 adrenergic agonist, has been used to treat Tourette syndrome (TS) for nearly 3 decades. This first-tier medication is especially recommended for children and adolescents with a combination of attention-deficit/hyperactivity disorder and mild tics. Although clonidine is thought to have a low rate of adverse effects (AEs), little is known about its tolerability profile in adult patients with TS. METHODS: This study investigated the prevalence and characteristics of AEs associated with clonidine through a retrospective chart review. We assessed 36 patients with TS (27 men; mean [SD] age, 24.6 ± 13.9; range, 10-62 years), of whom 32 (88.8%) had comorbid conditions (most common: attention-deficit/hyperactivity disorder, n = 12; obsessive-compulsive disorder, n = 9). RESULTS: Seventeen patients (47.2%) experienced AEs. Eleven patients (30.5%) withdrew clonidine because of the severity of AE (n = 5) or absence (n = 4)/reduction (n = 2) in efficacy. The most commonly reported AEs were sedation and headache. In most cases, AEs were mild and occurred with higher starting doses. In 12 patients (70.6%) who also took other psychotropic medications, cotherapy could have been linked to the appearance of AE. CONCLUSIONS: Our findings suggest that clonidine is a safe and well-tolerated medication in the TS population. Adults with TS treated with this medication experience mild and relatively infrequent AE; high starting dose and polytherapy seem to be the only clinically relevant risk factors for AE development.