Tics result from disruptions in the connection between the basal ganglia and its connections to the thalamus and cortex. Disruptions of gamma aminobutyric acid (GABA) as well as serotonin and histamine transmission are implicated.

Tics are often transient and benign. Cocaine and other stimulant use can cause tics. Neurodegenerative disorders can cause tics. Tourette syndrome, a childhood neurobehavioral disorder, is diagnosed when there are persistent motor and vocal tics.

Tics are seen in children treated with stimulant medications for attention deficit hyperactivity disorder (ADHD ). Available data on tics and stimulant medications are predominantly in children. Evidence is mixed on whether tics are caused/exacerbated by stimulant medications or the apparent increase is explained by higher prevalence of tics in children with ADHD [1]. Patients with ADHD do have a higher incidence of tics [2] and stimulant medications may only worsen tics at supratherapeutic doses [3]. Stopping stimulant medication reverses tics in some but not all patients, indicating that these medications may only worsen or unmask rather than induce tic disorders. Rarely, Tourette syndrome is precipitated with stimulant medications in children who previously did not exhibit symptoms.

Tics may also be seen as a part of tardive dyskinesia. Occasionally, mood stabilizers exacerbate tics.