Tourette syndrome or Tourettes syndrome (abbreviated as TS or Tourettes) is a common neurodevelopmental disorder that begins in childhood or adolescence. It is characterized by multiple movement (motor) tics and at least one vocal (phonic) tic. Common tics are blinking, coughing, throat clearing, sniffing, and facial movements. These are typically preceded by an unwanted urge or sensation in the affected muscles known as a premonitory urge, can sometimes be suppressed temporarily, and characteristically change in location, strength, and frequency. Tourettes is at the more severe end of a spectrum of tic disorders. The tics often go unnoticed by casual observers. Tourettes was once regarded as a rare and bizarre syndrome and has popularly been associated with coprolalia (the utterance of obscene words or socially inappropriate and derogatory remarks). It is no longer considered rare; about 1% of school-age children and adolescents are estimated to have Tourettes, and coprolalia occurs only in a minority. There are no specific tests for diagnosing Tourettes; it is not always correctly identified, because most cases are mild, and the severity of tics decreases for most children as they pass through adolescence. Therefore, many go undiagnosed or may never seek medical attention. Extreme Tourettes in adulthood, though sensationalized in the media, is rare, but for a small minority, severely debilitating tics can persist into adulthood. Tourettes does not affect intelligence or life expectancy. There is no cure for Tourettes and no single most effective medication. In most cases, medication for tics is not necessary, and behavioral therapies are the first-line treatment.
A few rare highly penetrant genetic mutations have been found that explain only a small number of cases in single families (the SLITRK1, HDC, and CNTNAP2 genes).Psychosocial or other non-genetic factors—while not causing Tourettes—can affect the severity of TS in vulnerable individuals and influence the expression of the inherited genes. Pre-natal and peri-natal events increase the risk that a tic disorder or comorbid OCD will be expressed in those with the genetic vulnerability. These include paternal age; forceps delivery; stress or severe nausea during pregnancy; and use of tobacco, caffeine, alcohol, and cannabis during pregnancy. Babies who are born premature with low birthweight, or who have low Apgar scores, are also at increased risk; in premature twins, the lower birthweight twin is more likely to develop TS.Autoimmune processes may affect the onset of tics or exacerbate them. Both OCD and tic disorders are hypothesized to arise in a subset of children as a result of a post-streptococcal autoimmune process. Its potential effect is described by the controversial hypothesis called PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections), which proposes five criteria for diagnosis in children. PANDAS and the newer pediatric acute-onset neuropsychiatric syndrome (PANS) hypotheses are the focus of clinical and laboratory research, but remain unproven. There is also a broader hypothesis that links immune-system abnormalities and immune dysregulation with TS.Some forms of OCD may be genetically linked to Tourettes, although the genetic factors in OCD with and without tics may differ.