Clinical pharmacology of nondopaminergic drugs in Tourette syndrome.

Treatment of tics and Gilles de la Tourette syndrome (GTS) by nondopaminergic drugs was initiated more than three decades ago. These approaches were driven by the wish to circumvent antipsychotic-related side effects (metabolic disturbances, parkinsonian syndromes, tardive dyskinesia) or to use these treatments as a valuable add-on therapy in patients at least partially refractory to antipsychotics. In this review, we will therefore discuss the potential value of treating tics with alpha2 receptor agonists, nicotine, tetrabenazine, GABA agonists, botulinum toxin, cannabinoids, and immune modulators (plasmapheresis, intravenous immunoglobulins, antibiotic prophylaxis). Future directions for clinical trials based on our expanding understanding of the pathophysiology of GTS with regard to cholinergic, glutamatergic, and histaminergic neurotransmission will also be briefly outlined.