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For further information, see CMDT Part 24-14: Movement Disorders

Key Features

Essentials of Diagnosis

  • Multiple motor and phonic tics

  • Symptoms begin before age 18 years

  • Tics occur frequently for at least 1 year

  • Tics vary in number, frequency, and nature over time

General Considerations

  • The diagnosis of the disorder is often delayed for years, the tics being interpreted as psychiatric illness or some other form of abnormal movement

  • Patients are thus often subjected to unnecessary treatment before the disorder is recognized


  • Tics are noted first in childhood, generally between the ages of 2 and 15

  • A family history is sometimes obtained

    • Mutation in the histidine decarboxylase gene on chromosome 15 is found in an autosomal dominant form of the disease

    • Prior reports of a linkage to chromosome 13q have been called into question

Clinical Findings

Symptoms and Signs

  • Motor tics

    • Initial manifestation in 80% of cases

    • Most commonly involve the face, head, shoulders, such as sniffing, blinking, frowning, shoulder shrugging, and head thrusting

  • Phonic tics

    • Initial symptoms in 20% of cases

    • Commonly consist of grunts, barks, hisses, throat clearing, coughs, verbal utterances including coprolalia (obscene speech)

  • A combination of different motor and phonic tics ultimately develop in all patients

  • Echolalia (repetition of the speech of others)

  • Echopraxia (imitation of others' movements)

  • Palilalia (repetition of words or phrases)

  • Some tics may be self-mutilating in nature

    • Nail-biting

    • Hair-pulling

    • Biting of the lips or tongue

  • Obsessive-compulsive disorder and attention deficit hyperactivity disorder are commonly associated and may be more disabling than the tics themselves

  • In addition to obsessive-compulsive behavior disorders, psychiatric disturbances may occur because of the associated cosmetic and social embarrassment

Differential Diagnosis

  • Wilson disease


Diagnostic Procedures

  • Examination usually reveals no abnormalities other than the tics



  • α-Adrenergic agonists are first-line therapies because of favorable side effect profile compared with typical antipsychotics

    • Clonidine (start 0.05 mg orally at bedtime, titrating to 0.3–0.4 mg orally daily, divided three to four times per day)

    • Guanfacine (start 0.5 mg orally at bedtime, titrating to a maximum of 3–4 mg orally daily, divided two times per day)

  • Many specialists favor use of tetrabenazine

  • Atypical antipsychotic risperidone (1–6 mg daily orally) is more effective than placebo in controlling tics and more effective than pimozide in improving symptoms of comorbid OCD, and may be tried before the typical antipsychotic agents

  • Haloperidol

    • Typical antipsychotic of choice

    • Started in a low daily dose (0.25 mg orally)

    • Gradually increase dose by 0.25 mg every 4 or 5 days until there is maximum benefit with a minimum of side effects ...

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