Tics are sudden, repetitive, non-rhythmic movements or vocalizations commonly associated with Tourette Syndrome (TS). The appearance of new, involuntary movements in your 20s can be alarming and prompts the question of whether this is the onset of TS. While TS is a neurodevelopmental condition with a strict age requirement for diagnosis, the onset of tics or tic-like behaviors can occur in adulthood. Understanding the medical distinctions between tic-related diagnoses is the first step toward accurate information and effective management.
The Definition and Age Requirement for Tourette Syndrome
Tourette Syndrome is classified as a neurodevelopmental disorder in the current diagnostic manual, the DSM-5. For a formal diagnosis of TS, an individual must have experienced multiple motor tics and at least one vocal tic for more than one year. A non-negotiable criterion for TS is that the onset of these tics must have occurred before the age of 18.
If a person begins experiencing tics for the first time at age 20, they cannot receive a diagnosis of Tourette Syndrome due to this diagnostic boundary. TS is considered the most complex end of the spectrum of primary tic disorders, rooted in genetics and brain development. Tics are often preceded by a feeling of bodily tension or discomfort known as a premonitory urge, which is temporarily relieved by performing the tic. This urge and the ability to suppress the tic often distinguish primary tics from other involuntary movements.
What Happens When Tics Begin in Adulthood
When tics start after age 18, the condition is referred to as an adult-onset tic disorder, often categorized as a “Tic Disorder, Unspecified.” If the tics are present for over a year and are not due to another medical cause, they are considered a chronic tic disorder, even without a TS diagnosis. These may be categorized as a Chronic Motor Tic Disorder (only motor tics) or a Chronic Vocal Tic Disorder (only vocal tics). Although the age of onset excludes them from the formal Chronic Tic Disorder category, the symptoms are functionally similar.
The onset of tics in adulthood may represent a recurrence of a mild, transient tic disorder that was unnoticed in childhood. Alternatively, a person who had a mild, sub-threshold tic disorder in youth might experience a significant increase in severity in their 20s. This worsening can prompt a new search for a diagnosis, even if the disorder began earlier. Regardless of the specific label, the symptoms are diagnosable and can be treated using the same therapeutic approaches as childhood-onset disorders.
Secondary Causes of Adult-Onset Tic-Like Behaviors
A primary focus for new-onset tics in adulthood is ruling out secondary causes, where tics are a symptom of an underlying medical issue rather than an idiopathic neurodevelopmental condition. Consulting a neurologist is an important step to explore these potential causes, often classified as secondary tic disorders. Certain medications, including stimulants for ADHD or specific antipsychotic drugs, are known to cause tic-like movements as a side effect, sometimes leading to tardive tics. Drug use, such as a cocaine binge, has also been documented as a trigger.
Underlying neurological conditions can also manifest with tics or tic-like behaviors, which is why a thorough medical evaluation is necessary. Examples include tics that develop following a head injury, a stroke, or infections that affect the central nervous system, such as encephalitis. These acquired conditions can disrupt the basal ganglia, the part of the brain responsible for movement control, leading to the development of tics. In some cases, tics that begin in adulthood are classified as Functional Neurological Disorder (FND), where the tics are psychogenic and not rooted in the same neurobiology as primary tic disorders. FND tics often lack a premonitory urge, may be inconsistent, and can worsen significantly when the person is observed.
Treatment and Coping Strategies for Adult Tic Disorders
For managing adult tic disorders, behavioral therapy is considered the first-line intervention. The most scientifically validated approach is Comprehensive Behavioral Intervention for Tics (CBIT), an expansion of Habit Reversal Training (HRT). This therapy teaches patients to become more aware of the premonitory urge that precedes a tic.
The next step in CBIT involves Competing Response Training. Here, the individual learns to perform a voluntary movement physically incompatible with the tic whenever they feel the urge. This brief, competing response is held until the urge subsides. CBIT also incorporates relaxation techniques and strategies to modify environmental factors that may worsen tic severity. For more severe cases, pharmacological options are available, primarily alpha-2 adrenergic agonists or dopamine-blocking agents, which are considered second-line treatments after behavioral therapy.