Tic (Movement) Disorders

What tics are

Tics are sudden, quick and repetitive, but not rhythmic. They vary in type and intensity over weeks and months, often moving from one body part to another. Most people feel a premonitory urge before a tic, a building itch, pressure or tension that the tic briefly relieves. Tics can often be held back for a short time, but this takes effort and the urge builds.

Eye and face tics are often the first to appear, which is why parents may first notice abnormal eyelid movements such as excessive blinking.

Types of tic disorder

All require onset before age 18 and that the tics are not due to a medicine or another medical condition.

Tics vs other movement disorders

Several conditions cause involuntary movements that can be mistaken for tics:

Medicines can also cause movements: antipsychotics can cause tardive dyskinesia, and stimulants or other drugs can sometimes bring out tics.

Causes and risk factors

Tic disorders arise from differences in the circuits linking the basal ganglia, frontal cortex and thalamus, which help filter and control movements. Contributing factors:

• Genetics: tics run strongly in families
• Sex: boys are affected 3 to 4 times more often than girls
• Pregnancy and birth factors: smoking in pregnancy, low birth weight and prematurity are linked to higher risk
• Co-occurring conditions: ADHD and OCD are common, along with anxiety, learning differences and autism

Tics typically get worse with stress, excitement, tiredness and illness, and improve during focused activities such as sport, music or gaming.

Tics that start in adulthood

New tics after age 18 are uncommon and need medical review. Possible explanations include:

• tics from childhood that were mild or forgotten and have returned
• secondary tics from stroke, brain injury, infection, medicines (such as stimulants or lamotrigine) or drug use
• functional tic-like behaviors, a form of functional neurological disorder. A rise in sudden-onset, complex tic-like movements and vocalizations, mainly in adolescent girls and young women, was seen from 2020, often linked to stress and social media exposure. These usually start abruptly with complex movements, unlike childhood tics, and are treated differently.

Diagnosis

There is no blood test or scan for tic disorders. The diagnosis is clinical, based on:

• a history of the tics: when they started, which body parts, how they change, and whether an urge comes first
• watching the tics, sometimes from home videos, since many people suppress them in the clinic
• a neurological examination, which is otherwise normal
• screening for ADHD, OCD, anxiety, mood problems and learning issues

Tests such as EEG, MRI or blood tests are only needed when the history is atypical, for example with loss of awareness, regression, adult onset or other neurological signs.

Treatment

Many people with tics need no treatment. When tics cause pain, social difficulties or interfere with daily life, options include:

Education and support

Explaining tics to the person, family and school reduces stress, which in turn can reduce tics. Avoid asking a child to stop or drawing attention to tics.

Behavioral therapy

Comprehensive Behavioral Intervention for Tics (CBIT) is the first-line treatment recommended by the American Academy of Neurology. It teaches awareness of the premonitory urge and a "competing response", a less noticeable action that makes the tic hard to perform, plus strategies for handling triggers. It typically involves 8 to 10 sessions and can be delivered online. Exposure and response prevention is another effective approach.

Medicines

• Alpha-2 agonists (guanfacine, clonidine): often tried first in children, especially with ADHD
• Antipsychotics such as aripiprazole, risperidone, haloperidol and pimozide: more effective for severe tics but with side effects such as weight gain, sleepiness and movement problems
• Topiramate and VMAT2 inhibitors in some cases
• Botulinum toxin injections for a single bothersome motor or vocal tic

ADHD and OCD are treated alongside tics, and stimulant ADHD medicines are usually safe for people with tics.

Deep brain stimulation

Reserved for adults with severe, disabling Tourette syndrome that has not responded to other treatment.

Outlook

Most childhood tics fade or improve greatly by the late teens or early 20s. Provisional tics often disappear within months. About a third of people with Tourette syndrome become tic-free by adulthood, and many more have only mild tics. Co-occurring conditions often have a bigger effect on daily life than the tics themselves, so treating them is important.

Frequently asked questions

What is the difference between a tic and a twitch?

A tic is a sudden, purposeful-looking movement or sound, like blinking, shrugging or sniffing, often preceded by an urge that the tic relieves. It can be held back briefly. A twitch, such as an eyelid flicker or muscle fasciculation, is a small involuntary quiver with no urge and no way to suppress it.

What are the types of tic disorders?

There are three main types: provisional tic disorder, where tics have lasted less than a year; persistent motor or vocal tic disorder, with only one type of tic for a year or more; and Tourette syndrome, with multiple motor tics and at least one vocal tic for a year or more.

Can adults develop tics?

Yes, but new tics in adulthood are uncommon and should be evaluated. They may be a return of childhood tics, or be caused by a brain injury, stroke, infection or medicine. Sudden, complex tic-like movements can also be a functional neurological disorder, which is treated differently.

Are tic disorders caused by anxiety?

No, anxiety does not cause tic disorders, but stress and anxiety commonly make tics worse. Anxiety disorders also often occur alongside tic disorders. Treating anxiety can reduce how often tics happen, even though it does not remove the underlying tendency.

Do tics go away on their own?

Often, yes. Many childhood tics disappear within a year, and most persistent tics and Tourette syndrome improve during the late teens. Tics typically wax and wane, so a worse period does not mean they will stay that way.