The urge to blink, grimace, jerk the head, move in some other way, or make a sound is irresistible, and the action is not voluntary.
Doctors base the diagnosis on symptoms.
Many tics disappear on their own, but if they are troublesome or severe, comprehensive behavioral intervention for tics and sometimes clonidine or antipsychotic drugs may help.
Tics vary widely in severity. One in five children has a tic of some sort for a period of time. Many of these tics are mild and often not recognized as a disorder by parents and doctors. Tourette syndrome is the most severe tic disorder and occurs in fewer than 1 in 100 children. Tics are 3 times as likely to occur in boys as in girls.
Tics begin before age 18 years (typically between ages 4 years and 6 years), increase in severity to a peak at about age 10 to 12 years, and decrease during adolescence. Eventually, most tics disappear. However, in about 1% of children, tics persist into adulthood.
Children with tics may have other disorders such as
Obsessive-compulsive disorder Obsessive-Compulsive Disorder (OCD) and Related Disorders in Children and Adolescents Obsessive-compulsive disorder is characterized by recurring, unwanted, intrusive doubts, ideas, images, or impulses (obsessions) and unrelenting urges to do actions (compulsions) to try to lessen... read more (OCD)
These disorders often interfere more with children's development and well-being than the tics. Sometimes tics first appear when children with ADHD are treated with a stimulant drug such as methylphenidate. These children probably have an underlying tendency to develop tics.
Adolescents (and adults) with tics may also have
Classification of Tic Disorders
There are three major types of tic disorder:
Provisional tic disorder: Children have had motor and/or vocal tics for less than a year.
Persistent tic disorder (chronic tic disorder): Children have had motor or vocal tics (but not both) for more than a year.
Tourette syndrome: Children have had both motor and vocal tics for more than a year.
Typically, children begin with provisional tic disorder and sometimes go on to develop persistent tic disorder or Tourette syndrome.
Causes of Tic Disorders
The cause of tic disorders is not known, but tic disorders often occur in families, so doctors think heredity plays a part.
Sometimes people who have another disorder, such as Huntington disease Huntington Disease Huntington disease is a hereditary disease that begins with occasional involuntary jerking or spasms, then progresses to more pronounced involuntary movements (chorea and athetosis), mental... read more or a brain infection (encephalitis Encephalitis Encephalitis is inflammation of the brain that occurs when a virus directly infects the brain or when a virus, vaccine, or something else triggers inflammation. The spinal cord may also be involved... read more ), develop tics. Tics can also result from use of certain drugs, such as cocaine or amphetamines. However, tics caused by other disorders or by drugs are not considered a tic disorder.
In children who have or have had a streptococcal (strep) infection Streptococcal Infections Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure How Bacteria Shape Up) cause many... read more , tics and/or symptoms of OCD sometimes start suddenly or become dramatically worse within a day. Such cases are called pediatric autoimmune neuropsychiatric disorder associated with streptococcus (PANDAS). Some people think that antibodies produced by the body to fight the streptococcal bacteria may cause tics (or OCD) or make tics worse. However, most investigators think that the proof of this connection is lacking.
Symptoms of Tic Disorders
Before a tic occurs, an urge to do the tic may be felt. This urge is similar to the need to sneeze or scratch an itch. Tension builds up, usually in the affected body part. Giving in to the tic provides brief relief.
The tic can sometimes be postponed for seconds to minutes but only with conscious effort and difficulty. Usually, the urge to do the tic eventually becomes irresistible. Trying to control tics is usually difficult, especially during times of emotional stress. Stress and fatigue can make tics worse. However, tics often also become worse when the body is relaxed, as when watching TV. Calling attention to a tic, particularly in children, may make the tic worse. Typically, tics do not occur during sleep, and they rarely interfere with coordination. Tics may lessen when people are concentrating on a task such as school or work activities or when people are in an unfamiliar place.
People with severe tics, particularly Tourette syndrome, may have difficulty functioning and experience considerable anxiety in social situations. In the past, they were shunned, isolated, or even thought to be possessed by the devil. They may become impulsive and aggressive and behave in self-destructive ways.
Children with severe tic disorders or Tourette syndrome are more likely to have another disorder, such as OCD, ADHD, and/or learning problems. These problems seem to result from the brain abnormalities that cause tics and Tourette syndrome. However, when a tic disorder is severe, the extraordinary stresses of living with the disorder may make these problems worse.
Tics tend to be similar at any given time, but they vary in type, intensity, and frequency over a period of time. Sometimes they start suddenly and dramatically. They may occur several times an hour, then almost disappear for many months.
Types of tics
Tics may be
Simple or complex
Motor or vocal
Simple tics are extremely brief. They may begin as nervous mannerisms.
Complex tics last longer and may combine several simple tics. In some complex tics, people may call out obscenities or words related to feces (called coprolalia). Although people often associate coprolalia with Tourette syndrome, at least 85% of people with Tourette syndrome do not have coprolalia. Complex tics may appear purposeful, as in coprolalia or when a person repeats another person's movements or words, but they are not intentional.
Did You Know...
Diagnosis of Tic Disorders
A doctor's evaluation
Early diagnosis of a tic disorder can help parents understand that the tics their children have are not intentional and that punishment cannot stop the tics and may even make them worse.
The diagnosis is based on the symptoms and their duration.
To distinguish Tourette syndrome from other tic disorders, doctors may have to evaluate children periodically over time.
Doctors also check children for disorders that often accompany tics, such as ADHD and OCD.
Treatment of Tic Disorders
Reassurance and support
Comprehensive behavioral intervention for tics
If symptoms are mild, reassurance is often best, with as little attention paid to the tic as possible until it disappears on its own. Treatment can often be avoided if the family understands the disorder and if the disorder is explained to and understood by the child's teachers and schoolmates.
Comprehensive behavioral intervention for tics (CBIT)
CBIT is a type of behavioral therapy. It may help some older children manage their tics.
CBIT includes the following:
Cognitive-behavioral techniques (such as habit reversal training)
Education about tics
Habit reversal training involves teaching children new behaviors to substitute for the tics. For example, if the tic involves shrugging their shoulders, they may be taught to stretch out their arms until the urge to shrug passes.
Education may involve teaching children (and their parents) to identify situations in which tics occur or become worse.
Drugs to stop tics are recommended only if tics persist and are interfering with the child's activities or self-image. The lowest dose needed to make tics tolerable is used, and doses are decreased as tics lessen.
Clonidine is a drug that occasionally helps. It can also help control anxiety and hyperactivity, which may accompany a tic disorder. However, clonidine can cause drowsiness, which may interfere with the child's daytime activities. Although clonidine is also used to treat high blood pressure, it rarely causes low blood pressure in children. However, after children have taken clonidine for a while, suddenly stopping clonidine may cause blood pressure to increase temporarily.
For severe tics, antipsychotic drugs Antipsychotic drugs Schizophrenia is a mental disorder characterized by loss of contact with reality (psychosis), hallucinations (usually, hearing voices), firmly held false beliefs (delusions), abnormal thinking... read more may be effective even though psychosis is not the cause of tics. Effective drugs include risperidone, haloperidol, pimozide, and olanzapine. Side effects include restlessness, muscle stiffness, symptoms similar to those of Parkinson disease (parkinsonism Parkinsonism Parkinsonism refers to symptoms of Parkinson disease (such as slow movements and tremors) that are caused by another condition. Parkinsonism is caused by brain disorders, brain injuries, or... read more ), and tardive dyskinesia, which consists of repetitive slow involuntary movements. However, these side effects are uncommon because the doses used to treat tics are low.
Treatment of other problems
Children who have tics and who are struggling in school should be evaluated for learning disorders and provided with support as needed.
If obsessive or compulsive traits are bothersome, a drug such as a selective serotonin reuptake inhibitor (SSRI), which is an antidepressant, may be useful.
ADHD Treatment Attention-deficit/hyperactivity disorder (ADHD) is poor or short attention span and/or excessive activity and impulsiveness inappropriate for the child’s age that interferes with functioning... read more can be difficult to treat because the stimulant drugs typically used to treat it may worsen tics. Sometimes low doses of these drugs can effectively treat ADHD without making tics worse. Or a drug that is not a stimulant can be used to treat ADHD.