Recognition and Management of Tourette's Syndrome and Tic
- MOHAMMED M. BAGHERI, M.D., JACOB KERBESHIAN, M.D., and LARRY
- University of North Dakota School of Medicine and Health
- Grand Forks, North Dakota
Tic disorders and Tourette's syndrome
are conditions that primary care physicians are likely to encounter. Up to 20
percent of children have at least a transient tic disorder at some point. Once
believed to be rare, Tourette's syndrome is now known to be a more common
disorder that represents the most complex and severe manifestation of the
spectrum of tic disorders. Tourette's syndrome is a chronic familial disorder
with a fluctuating course; the long-term outcome is generally favorable.
Although the exact underlying pathology has yet to be determined, evidence
indicates a disorder localized to the frontal-subcortical neural pathways.
Tourette's syndrome is commonly associated with attention-deficit/hyperactivity
disorder, obsessive-compulsive disorder, behavior problems and learning
disabilities. These comorbid conditions make the management of Tourette's
syndrome more challenging. Management of Tourette's syndrome should include
timely and accurate diagnosis, education, and behavior or pharmacologic
interventions. Use of neuroleptic medications and dopamine D2 antagonist drugs can be effective but may be
associated with significant side effects.
Primary care physicians are
often the first physicians to be consulted about tics. Tics are defined as
sudden, rapid, purposeless, repetitive, nonrhythmic, stereotyped movements or
vocalizations.1 Tics are either transient,
with a duration of less than 12 consecutive months, or chronic, with a course
that lasts more than a year, and can be either primary (idiopathic) or
secondary. Common simple tics are eye blinking, shoulder jerking, picking
movements, grunting, sniffing and barking.1
Complex tics include facial grimacing, arm flapping, coprolalia (use of obscene
words), palilalia (repeating one's own words) and echolalia (repeating
another's words or phrases). Table 1 lists some common motor and vocal
A Review of the Most Common Tics
|Phonic or vocal tics
|Sticking tongue out
|Phonic or vocal tics
|Repeating parts of words or phrases
|Talking to oneself (multiple characters)
|Assuming different intonations
|Use of obscene words
|Adjusting or picking at clothing
|Complex touching movements
|Kissing self or others
Tourette's syndrome is a chronic tic disorder that is characterized
by both motor and vocal tics, with onset in childhood. Table 2 lists
current diagnostic criteria for Tourette's syndrome.1 This disorder usually begins with simple tics and
progresses to more complex tics. Coprolalia was originally described as a
pathognomonic symptom by Gilles de la Tourette, but it occurs in only 8 to 39
percent of patients, mostly males, and is not required for a diagnosis.2-5 Tics typically have a peak period of
recognition in the early school years, although a careful clinical history will
often determine that they have been present for years. Tourette's syndrome has
a waxing and waning course, with one tic appearing and typically being replaced
by another, although in most cases multiple tics are present concomitantly.
Tics are often temporarily suppressible, sometimes for minutes, occasionally
for hours. Some patients can suppress their tics during the school day or work
day. Tic suppression typically causes a "build-up" of tics that is then
discharged at home, often in flurries for one to two hours.
Tics have come to be recognized as a common component of development.
It has been estimated that as many as one in five children has had a tic at
some point in the first 10 years of life,6-8
although accurate epidemiologic data are limited. These tics typically are
transient, lasting less than one year. Some patients acquire longstanding
chronic tics, usually motor tics, that may persist for years. Motor tics are
more common than vocal tics.
The prevalence of Tourette's syndrome is one to 10 cases per
10,000.7-9 In North Dakota school-aged
children, the rate is 5.2 cases per 10,000.8
In North Dakota adults, the rate is 0.5 per 10,000.9 Tourette's syndrome is three to nine times more
frequent in males than in females.9 The mean age of onset is six to
Course of the Disorder
In most children, Tourette's syndrome has a fluctuating course.
Anxiety, stress and fatigue often intensify tics. Tics are usually
significantly reduced during sleep or when the patient is focused on an
activity. Psychoactive drugs, particularly cocaine and stimulants, have a
tendency to worsen tics.
In most cases, tics peak in severity between nine and 11 years of
age. In one study,10 73 percent of patients
(median age of 18 years) reported that their tics had disappeared or
considerably decreased at follow-up. In another follow-up study,11 only 9 percent of study subjects had severe
symptoms after five to 15 years. In our experience, about 85 percent of
patients have remission or improve considerably as adults (Figure 1).
Between 5 and 10 percent of patients continue to have unchanged or
worsening symptoms into adolescence and adulthood. In this population, the
likelihood of tics continuing for decades is substantial. Patients in their
seventh, eighth and ninth decades of life may have tics that have been present
since childhood. In most older patients, the tics tend to become quite stable
over time, although occasionally new tics will be acquired. There is no
reliable way to predict which children will have a poorer prognosis.
Diagnostic Criteria for Tourette's Disorder
- Both multiple motor and
one or more vocal tics have been present at some time during the illness,
although not necessarily concurrently.
- The tics occur many
times a day (usually in bouts) nearly every day or intermittently throughout a
period of more than one year, and during this period there was never a tic-free
period of more than three consecutive months.
- The disturbance causes
marked distress or significant impairment in social, occupational or other
important areas of functioning.
- The onset is before age
- The disturbance is not
due to the direct physiologic effects of a substance (e.g., stimulants) or a
general medical condition (e.g., Huntington's disease or postviral
with permission from American Psychiatric Association. Diagnostic and
statistical manual of mental disorders. 4th ed. Washington, D.C.: American
Psychiatric Association, 1994:103. Copyright 1994.
|Clinical Course of Tourette's Syndrome
|FIGURE 1. The clinical course of Tourette's syndrome. Onset
typically occurs before seven years of age and the disorder is usually
recognized two to three years after onset. In most children, the severity peaks
at nine to 11 years of age. About 5 to 10 percent of patients have an
intensifying course with little or no improvement. In about 85 percent of
patients, symptoms diminish during and after adolescence.
stress and fatigue may intensify tics in children.
The precise etiology of Tourette's syndrome is unknown. Tics are
believed to result from a tripartite dysfunction in the central nervous system.
Imaging techniques have implicated the basal ganglia and frontal cortex in the
pathogenesis of Tourette's syndrome.12-14 The
second source of abnormality is thought to be inappropriate regulation of
neurotransmitters, especially dopamine.15
Strong evidence indicates that dopamine excess or supersensitivity of the
postsynaptic dopamine receptors is the underlying pathophysiologic mechanism of
Tourette's syndrome.16-19 The third
hypothesis of dysfunction is a neurophysiologic deficit secondary to
neurotransmitter abnormalities, resulting in failure of inhibition of the
frontal-subcortical motor circuits.19-22 This
area has prominent interconnections with the basal ganglia. As a result, the
tic-related neural circuits for throat clearing, sniffing, eye squinting or
facial grimacing may run too frequently and out of synchrony with those for
other motor movements. Stress and anxiety may neurochemically intensify this
Problems Associated with Tourette's Syndrome and Percentage of Patients
with These Problems
|Coprolalia (8 to 25%)
|Compulsive behaviors (30 to 50%)
|Obsessive thoughts (30%)
|Copropraxia (1 to 6%)
|Echophenomena (30 to 60%)
|Behavior problems (60 to 80%)
|Obscene words and statements
|Precise arrangement of objects
|Writing and rewriting of letters until perfect
|Washing hands repeatedly
|Mental echolalia (words, phrases)
|Counting or grouping
|Thinking about forbidden actions (standing on desk in school, kissing
teacher, touching others sexually)
|Thinking about exposing oneself
|Touching others sexually
|Placing head on another's breast
|Picking at buttocks
|Echolalia (repeating others' words or statements)
|Echopraxia (imitating others' actions)
|Palilalia (repeating one's own statements, words or parts of
This list is not exhaustive, since a wide range of symptoms may occur in
patients with Tourette's syndrome.
|Raw, chapped hands from
|Unproductive hours spent
working on homework
| Erasure holes in test
papers and schoolwork
|Repeated requests for
family members to repeat strange phrases or repeatedly asking the same
| Persistent fear of
| Dramatic increase in
amount of laundry
| Exceptionally long time
preparing for bed
| Continual fear that
something terrible will happen to someone else
| Difficulty leaving the
| Constant lateness
| Hoarding of useless
| Peculiar patterns of
walking or sitting
| Inability to get
dressed within a reasonable period of time
Comorbidity and Complications
Tic disorders and Tourette's syndrome are frequently accompanied by
other conditions. The three most frequent comorbid conditions are
attention-deficit/hyperactivity disorder (ADHD) (about 50 percent of patients
with Tourette's syndrome have accompanying ADHD), learning disabilities (25 to
30 percent of patients) and obsessive-compulsive disorder (25 to 40 percent of
patients).2 Tables 3 and 4 list common
An extremely important concept in the evaluation and development of
treatment programs for patients with tic disorders is the recognition that
multiple undiagnosed comorbid conditions may result in a moderate to severe
level of functional impairment. Under such circumstances, it is necessary to
identify each of these conditions, since it may be necessary to treat one, two
or even three of the conditions in order to improve functioning. Other
complications include depression, sleep problems, social discomfort and
Tics are classified as either primary (idiopathic) or secondary.
Table 5 lists secondary causes of tics. Idiopathic tic disorders and
Tourette's syndrome are multifactorial in etiology. Genetic predisposition is
important, but environmental factors influence the risk, the severity and the
course of the disorder. Studies show a concordance rate of about 60 percent for
Tourette's syndrome in monozygotic twins and 10 percent in dizygotic
twins.23,24 The mode of transmission of
Tourette's syndrome is controversial.
One genetic theory advocates an autosomal dominant pattern of
inheritance with incomplete penetrance and variable expression.23,24 In our experience, comorbid conditions have a
multiple effect on overall severity. As a result, it will often be necessary to
develop intervention plans for these comorbid conditions, even if the severity
of each individually is low. The phenotypic variation that is also seen in
monozygotic twins may be associated with differences in dopamine D2-receptor binding in the caudate nucleus.25
Walkup and associates26 reject the
autosomal dominant theory and propose a mixed model of inheritance that
includes an additive major locus combined with a multifactorial background.
Male offspring are more prone to express tic syndromes, and female offspring
are more prone to have obsessive-compulsive disorder without tics. This
observation supports the theory that obsessive-compulsive disorder and chronic
tic disorder are alternate phenotypes of a putative Tourette's syndrome
gene.23,24 An area of increasing research
interest is a subgroup of persons with Tourette's syndrome linked to a
streptococcus-induced autoimmune neuropsychiatric condition presenting as
Tourette's syndrome, obsessive-compulsive disorder, or both.27
Secondary Causes of Tic Disorders
Carbon monoxide poisoning
Fragile X syndrome
disorders manifesting tics
Drugs reported to
or worsen preexisting tics
Opioids and opioid
with permission from Kumar R, Lang AE. Tourette syndrome. Secondary tic
disorders. Neurol Clin 1997;15:309-31.
| Most tics
associated with Tourette's syndrome diminish or disappear after
The single most important component of management is an accurate
diagnosis. Tics should be differentiated from other movement disorders such as
chorea, stereotypy and dystonias. Tics occur suddenly during normal activity,
whereas chorea is a pattern of nonrepetitive irregular movements that are not
stereotypic. Dystonia is stereotypic but usually not rapid and usually does not
have a waxing and waning course, although it may have an intermittent course.
The second step in management is to rule out the secondary causes of
tic disorders. The degree of inclusiveness of the work-up for Tourette's
syndrome depends on the patient's history, the family history and specific
patient characteristics.26-29 A complete
general physical examination, with specific attention to the neurologic part of
the examination, is a prerequisite. The thyroid-stimulating hormone (TSH) level
should be measured in most patients, since tics often occur concomitantly with
hyperthyroidism. A throat culture should be checked for group A beta-hemolytic
streptococcus, and an antistreptolysin-O (ASO) titer and levels of anti-DNAse B
should be obtained in patients with a very rapid onset of symptoms or symptoms
that appear to wax and wane with bouts of pharyngitis or otitis media. The
correlation of microbiologic and serologic evidence of streptococcal infection
with a single occurrence of tic exacerbation is insufficient to make a
diagnosis of streptococcus-induced, autoimmune-caused Tourette's syndrome. Such
findings are likely to be nonspecific, especially in a pediatric population. A
pattern of correlation that varies over time with the presence or absence of
symptoms would be more convincing.
An electroencephalogram is likely to be nonspecifically abnormal and
is useful only in patients in whom it is difficult to differentiate tics from
manifestations of epilepsy. Imaging studies are not likely to be helpful. Other
studies would depend on the clinical presentation. For example, a urine drug
screen for cocaine and stimulants should be considered in a teenager with
sudden onset of tics and inappropriate behavior symptoms. A person with a
family history of liver disease associated with a parkinsonian or hyperkinetic
movement disorder should undergo serum copper and ceruloplasmin studies to rule
out Wilson's disease. The basic work-up is usually appropriate in a patient
with an insidious onset, a developmental progression of tics and a family
history of tics or obsessive-compulsive disorder.
| Management of Tic Disorders
*--Common comorbid conditions include
obsessive-compulsive disorders, attention-deficit/hyperactivity disorder and
include education of patients, school personnel and parents, and initiation of
supportive counseling and behavior therapy.
|FIGURE 2. An algorithm for the management of tic disorders.
| Tics should be
differentiated from other movement disorders such as chorea, stereotypy and
The following steps should be included in the preliminary management
of tic disorders: (1) a detailed history--age of onset, family history, other
medical concerns, evidence of waxing and waning course; (2) descriptions of
reported and observed behaviors; and (3) specific follow-up observations or
Figure 2 provides an algorithmic approach to the management of
tic disorders. The appropriate diagnosis of a tic disorder provides an
explanation for the bizarre and inexplicable behaviors occurring in these
children, who may otherwise appear to be normal. In our experience, we find
that as we intensify our educational efforts toward parents, affected children
and school personnel, the number of children who require pharmacologic
intervention can be markedly reduced. We have demonstrated that the need for
pharmacologic intervention for tics has been reduced by approximately 50
percent over the past 15 years through an aggressive program of providing
written information, linking parents with support groups, in-service training
for school staff and telephone consultations.
Positive reinforcement programs appear
to be most helpful in the management of tic disorders. Target behaviors may be
categorized into two groups: (1) skill deficiencies, or areas that initially
require concentration to build social and academic skills; and (2) behavior
excesses, in which the goal is to help the patient decrease the frequency of
these behaviors. Caution should be exercised in the management of behavior
excesses, since some children who undergo behavior modification to directly
target the Tourette's syndrome symptoms have an exacerbation of symptoms.29
The therapeutic goal should
not be to decrease tics to a level at which they are no longer noticeable. The
goal in tic control is to use the lowest dosage of medication that will enhance
the patient's functioning to an acceptable level. Often this will require only
modest levels of tic reduction.
The most commonly employed pharmacologic interventions in the
treatment of Tourette's syndrome in children and adults are the neuroleptic
agents haloperidol (Haldol) and pimozide (Orap), and the atypical neuroleptic
agent risperidone (Risperdal); the alpha2-adrenergic presynaptic agonists clonidine
(Catapres) and guanfacine (Tenex [this medication is not labeled for use in
children under 12 years of age]); and, less often, the benzodiazepine
clonazepam (Klonopin). For tics of mild to moderate severity, or in patients
who are wary of neuroleptic side effects, an initial trial of clonidine or
guanfacine is prudent. These medications are modestly effective in tic control
and have a range of less specific benefits. Many children taking them may be
less irritable or less impulsive, and manifestations of ADHD may improve as
well. Clonidine may be used in a dosage range of 0.05 mg twice daily to 0.1 mg
four times daily, and guanfacine in the range of 0.5 mg twice daily to 1.5 mg
The potent dopamine D2 antagonist
drugs are the most effective in terms of tic reduction but carry the greatest
burden of potential side effects. Haloperidol, pimozide and risperidone are
frequently used.30 Side effects include
sedation, weight gain, impaired academic performance, social anxiety with
school refusal in children and extrapyramidal movement symptoms, including
tardive dyskinesia. Tardive dyskinesia is a potentially irreversible
neuroleptic-mediated movement disorder characterized by choreoathetoid
movements that may be difficult to distinguish from tics. Haloperidol may be
used in the dosage range of 0.5 to 4 mg at bedtime, and pimozide at 1 to 8 mg
at bedtime. When pimozide is used, baseline and follow-up electrocardiograms
Clonazepam has some use in the treatment of tics and Tourette's
syndrome. Side effects include sedation, weight gain, impaired academic
performance, social anxiety with school refusal in children and a worsening of
attention in children with comorbid ADHD. The dosage range for clonazepam is
0.25 mg twice daily to 1 mg three times daily.
| Many patients
with Tourette's syndrome have comorbid neuropsychiatric conditions, such as
attention-deficit/ hyperactivity disorder, obsessive-compulsive disorder or
Most patients with Tourette's syndrome require medication for up to
one to two years. About 15 percent of patients require long-term medication for
tic control. When tics appear to be stable and adequately controlled for a
period of four to six months, a slow and gradual reduction in medication,
titrated to the point of emergence of functionally impairing tics, should
follow. With such a strategy, occasional drug holidays may be possible in some
patients with the waning of tics. With the waxing of tics, incremental
increases in medication may follow. Many patients with Tourette's syndrome have
comorbid neuropsychiatric conditions, and treatment for these conditions may be
Treatment of comorbid ADHD has been controversial because of reports
that stimulants hasten the onset or increase the severity of tics in some
patients.30-32 This observation alone may not
be a contraindication for stimulant treatment in patients with significant
symptoms of ADHD.31 Stimulants alone may not
substantially worsen the course or severity of the disorder. In some cases, it
may be necessary to treat both the ADHD and the Tourette's syndrome with a
stimulant in combination with either clonidine or guanfacine, or with a
neuroleptic agent. A trial of clonidine or guanfacine alone may be sufficient
to adequately treat both conditions. When possible, polypharmacy should be
minimized, especially in children.
Treatment of obsessive-compulsive disorder with selective serotonin
reuptake inhibitors may be effective. With these medications, there is often a
significant delay between initiation of treatment and optimal therapeutic
response. This response may take as long as four to six weeks. Behavior therapy
is also effective in the treatment of obsessive-compulsive disorder.
Figure 33 is a simplified
scale that can be used to rate problematic behaviors, establish a baseline and
determine response to intervention. This approach is particularly helpful in
children with multiple development problems. In children with chronic problems,
a scale is especially helpful since it is often difficult to recall how much
progress has been made. As a general rule, the parents and teachers should each
complete three ratings of the child. These data, when combined with the
physician's assessment in the office, will provide a baseline of severity. The
rating scale may then be used to evaluate changes in response to interventions
or to monitor severity over time.
Behavior Rating Scale
| List of symptoms to be rated
| Time of day
(gym, home, etc.)
| Severity of problem (circle appropriate category)
||Absent Moderate Severe
||0 1 2 3 4 5 6 7 8 9 10
||0 1 2 3 4 5 6 7 8 9 10
||0 1 2 3 4 5 6 7 8 9 10
||0 1 2 3 4 5 6 7 8 9 10
||0 1 2 3 4 5 6 7 8 9 10
|These things make the symptoms better:
|These things make the symptoms worse:
|Questions I have:
3. Scale for rating problematic behaviors in children with Tourette's
Adapted from Goldenberg JN, Brown SB,
Weiner WJ. Coprolalia in younger patients with Gilles de la Tourette syndrome.
Mov Disord 1994;9:622-5.
Tics and Tourette's syndrome are not uncommon. Family physicians are
likely to be an important source of information, guidance and intervention for
this disorder. Additional information for patients, parents, teachers and
professionals is available from the Tourette's Syndrome Association, 42-40 Bell
Blvd., Bayside, NY 11361; telephone: 718-224-2999. Information about
attention-deficit/hyperactivity disorder is available from Children and Adults
with Attention Deficit/Hyperactivity Disorders (CH.A.D.D.), 81 Professional
Pl., Suite 201, Landover, MD 20785; telephone: 301-306-7070; and information
about obsessive-compulsive disorder is available from the Obsessive-Compulsive
Foundation, Inc. (OCF), 90 Depot St., P.O. Box 70, Milford, CT 06460-0070;
MOHAMMED M. BAGHERI, M.D.,
is serving a residency in dermatology
at the Mayo Clinic in Jacksonville, Florida. He is a graduate of the University
of North Dakota School of Medicine and Health Sciences.
JACOB KERBESHIAN, M.D.,
is clinical professor of neuroscience at
the University of North Dakota School of Medicine and Health Sciences and
program director of behavioral health services for the Altru Health System,
Grand Forks, N.D. Dr. Kerbeshian received his medical degree from the
University of Rochester School of Medicine and Dentistry, Rochester, N.Y., and
served a residency in child psychiatry at Strong Memorial Hospital, Rochester.
LARRY BURD, PH.D.,
is assistant professor of pediatrics and
neuroscience at the University of North Dakota School of Medicine and Health
Sciences, Grand Forks. Dr. Burd received his doctorate in community health
sciences from the University of Manitoba.
Address correspondence to Larry Burd,
Ph.D., MCRH-CETP, 1300 S. Columbia Rd., Grand Forks, ND 58202. Reprints are not
available from the authors.
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