What is Tourette Syndrome?

Tourette syndrome (TS) is a neuropsychiatric disorder characterised by repetitive, involuntary movements and vocalisations known as tics which typically develop in childhood. This condition is estimated to affect over 300,000 children and adults in the UK, and one school child in every hundred – it has been estimated that there is a prevalence of 0.7% from community-based research (Scharf et al, 2012).. As with other neurodevelopmental conditions, TS is more prevalent in males. Tics can be categorised as motor tics (involving movement) or vocal tics (involving sounds or speech). They can also be characterised by whether they are simple or complex. Simple tics are brief and involve a single muscle group. Examples include blinking, throat clearing, or head jerking. Complex tics are more intricate and involve a series of coordinated movements or sounds. Examples include touching objects, jumping, making gestures or repeating words.

Tourette syndrome typically begins in childhood, usually between the age of 2 and 9 years. The severity of symptoms can vary widely among individuals. TS is diagnosed based on clinical observations of tics over at least a year. The diagnosis can involve ruling out other medical or neurological conditions that might be causing the tics, although generally careful review of symptom history and an otherwise normal neurological examination suffice for this purpose. Tics often change over time, across a period of hours, days, weeks or months. This is called waxing and waning, meaning the tics can become more pronounced at times and lessen at other times. Environmental factors such as stress and excitement can also affect frequency and severity of tics. Iverson and Black (2022) suggest that ‘understanding these environmental impacts on tics can inform both treatment and parenting strategies. For example, understanding how parental reactions to tics reinforce tics can help parents understand how to best support their children’. There is a strong genetic component to TS, as it tends to run in families. Researchers have found that there are abnormalities in specific brain regions and chemical messengers in the brain.

It is thought that approximately half of children with a TS diagnosis will see a significant reduction in their symptoms as they approach adulthood (Groth et al, 2017). For a significant minority of people, tics will continue throughout their life, but symptoms are likely to wax and wane and for many may not impact on their daily function. However, an important minority of patients have continued impairing symptoms during adult life and this will likely be both men and women. Recent research seems to suggest that women may be particularly at risk of impactful tics.  Nilles et al (2023) found in adult women that ‘females had a higher frequency and intensity of motor tics than males (and were) associated with greater tic-related impairment’.

A myth about TS is that it involves swearing. This tic is known as coprolalia and is found in approximately 10% of young people diagnosed with TS (Cavanna and Rickards, 2013). Other symptoms which can be present but are rare include – copropraxia (obscene gestures), echolalia (repeating the words said by other people) and echopraxia (repeating other people’s gestures) (Kobierska et al 2014); Ganos et al 2012.

Many people experience a physical sensation – a premonitory urge/tic signal – before they express a tic. It has been compared to other physical sensations such as the need to itch or sneeze (Reese et al 2014). Although tics are involuntary, most people are able to suppress their tics for a short time. It can take a great measure of concentration – especially to begin with – to resist the urge to tic, but with practice a certain level of control can be applied. Some people will be able to suppress their tics more easily than others.

Impact of living with TS

The visible nature of tics can lead to stigma, embarrassment, anxiety, or depression related to their symptoms (Piedad and Cavanna, 2016; Malli et al 2016).

Patient support associations and individuals with TS often stress that it is important to note that while TS can be challenging, many individuals with the disorder lead fulfilling lives. Support from healthcare professionals, families, and communities can play a crucial role in helping individuals with TS manage their symptoms and thrive. The impact of living with TS is variable as the condition is unique to each individual and is experienced across a spectrum.  Living with TS can have a significant impact on various aspects of an individual’s life. The symptoms of TS, particularly the tics, can vary widely in terms of severity, frequency, and type. Here are some ways in which TS can impact different areas of life:

Social Interaction and Relationships

Tics are often noticeable and can lead to social challenges. Perhaps one of the biggest challenges for people living with TS is managing the reactions of others. There remains stigma attached to the condition, and it is still misunderstood as being ‘that thing where people swear’, and is often spoken of in derogatory terms.  Due to the unpredictable nature of TS, people may resist socialising; and therefore can feel ostracised from their community, and wider society. With loud or physically noticeable tics it can be difficult to sit in an audience at a concert or cinema, or in a library without attracting attention. Building and maintaining relationships can be challenging due to concerns about how others might react to tics.

Emotional Well-being

Tics can cause frustration, embarrassment, and anxiety, especially in situations where individuals want to control or suppress their tics. Living with a visible condition can lead to feelings of self-consciousness and stress. Mental health issues can become problematic with stress and pain creating psychological difficulties. Research from the Karolinska institute in Sweden even suggests a higher risk of suicide in people with TS (Fernandez de la Cruz, et al 2017). Sleep disturbances, such as insomnia or sleep-related movement disorders, such as tics, can impact individuals with TS, leading to fatigue and reduced overall quality of life (Ricketts et al 2022). It is also suggested that sleep difficulties can in turn affect tic severity.

Academic and Occupational Challenges

Tics can interfere with focus and concentration, leading to challenges in academic settings or at work. Stigmatization and misunderstanding from teachers, coworkers, or supervisors can create  additional stress. Atkinson-Clement et al (2022) suggest that social stigma was a ubiquitous experience for young people with TS. Advocacy efforts are necessary to raise awareness and promote understanding about TS in educational and community settings.

Some individuals with TS may experience difficulties with learning, organization, planning, and problem-solving, which are collectively referred to as executive dysfunction. These challenges can impact academic and occupational functioning. Standing out from peers and being ‘different’ can be a source of anxiety, and young people with TS may fear being or be directly bullied because of their overt symptoms.  Giving some sort of psychoeducation in schools where a pupil has TS can be very beneficial (Nussey, Pistrang and Murphy, 2013). Recent research has found that teachers often feel they lack professional training to adequately understand the disorder (Ludlow et al 2022). Tourettes Action has many resources about supporting a child with TS in the classroom.

Quality of Life

Individuals with severe tics might experience physical discomfort or pain due to repetitive movements. Tics can be painful and in some cases can cause serious harm or injury. It has been suggested that tic-related pain has a significant physical and psychological impact which impacts daily living in people with tic disorders and affects their mental health (Taylor, Anderson & Davies, 2022).

Co-occurring conditions

Up to 85 percent of people with TS will have additional symptoms to tics. These co-occurring conditions may include ADHD, OCD, anxiety, as well as depression, sleep problems and sensory processing difficulties (Eddy and Cavanna, 2014) . The co-morbidities mean that children with TS and co-occurring conditions may present for treatment in CAMHS.  These additional features and conditions can, for some people, be more challenging to live with than the tics themselves. About two-thirds of children with tic disorders will meet the criteria for ADHD, and up to 50% per cent of children with ADHD also have a tic disorder (Cavana, Servo, Monaco, Robertson, 2009. Studies have shown higher anxiety symptoms in young people with Tourette Syndrome than those without TS (Lewin et al. 2011) Despite the prevalence of TS (1 in 100 school children) there are no National Institute for Health and Care Excellence (NICE) guidelines on Tourette Syndrome. NICE guidelines are evidence-based recommendations for health and care in England, and already exist for many other conditions such as ADHD and OCD. There are AAN (Pringsheim et al 2019) and European treatment guidelines for the treatment of tics in Tourette syndrome and chronic tic disorders (Cath et al 2011). The presence of comorbidities can complicate the management of TS and impact an individual’s overall well-being. Some common comorbidities associated with TS include:

Attention-Deficit/Hyperactivity Disorder (ADHD)

ADHD is one of the most common comorbid conditions with TS. It is characterized by difficulties with attention, impulsivity, and hyperactivity. However, methylphenidate on average improves tics in children with ADHD, and guanfacine or clonidine also can improve both tics and ADHD symptoms (Kurlan et al 2002).When managing both ADHD symptoms and tics clinicians should refer to the European Guidelines (Roessner et al 2022).

Obsessive-Compulsive Disorder (OCD)

OCD involves intrusive and distressing thoughts (obsessions) and repetitive behaviours or mental rituals (compulsions). There is a significant overlap between TS and OCD, with some individuals experiencing tics and obsessive-compulsive symptoms simultaneously. Behaviour therapy and medication treatment are often used in these patients. In more recent years the term Tourettic OCD (TOCD) has been used which consists of touching behaviour, symmetry concerns, and thoughts of exactness. Katz et al (2022) suggest that TOCD encapsulates ‘a need to repeat complex tics until “just right,” without cognitive or imaginal obsessions’. They suggest that ‘TOCD might be a condition distinct from both TS and OCD’ and suggest that it should be considered for inclusion as a distinct condition in the DSM in future. However other clinicians remain sceptical as to whether a new diagnosis is needed.

Anxiety Disorders

Individuals with TS may be more prone to experiencing anxiety disorders, such as generalised anxiety disorder, social anxiety disorder, or specific phobias. The stress of managing tics and potential social challenges can contribute to anxiety and tics are usually more severe or frequent when anxiety is present.

Mood Disorders (Depression and Bipolar Disorder)

Mood disorders, including depression and bipolar disorder, can occur alongside TS. The impact of living with a chronic condition and the challenges associated with tics can contribute to mood disturbances.

Autism Spectrum Disorder (ASD)

ASD is a neurodevelopmental condition and although not as co-morbidly prevalent as some other conditions it can be useful to look at the differences and similarities. The main symptoms of ASD are related to having difficulties with social communication and language, and also experiencing ridged and repetitive behaviours. there can be some overlap between TS and ASD, leading to shared features or diagnostic confusion such as echolalia and both ASD and TS have movements associated with them. In TS, physical tics are involuntary and usually accompanied by a physical sensation (premonitory urge) before the tic. In ASD, movements are called stereotypies (or stimming) and generally appear as more constant  or rhythmic movements such as hand flapping and waving or rocking. Whereas tics wax and wane over time and are rapid and random, stereotypies tend to be more predictable and whilst both stereotypies and tics tend to increase during periods of excitement or stress, stereotypies are generally only seen at these times, whereas tics can be experienced at any time and often when the person is calm and at rest.  It’s important to differentiate between TS and ASD when assessing an individual’s symptoms.

Understanding and addressing these comorbidities is crucial for providing comprehensive care to individuals with TS. Treatment plans should be tailored to address both the tics and any co-occurring conditions, taking into account potential interactions between treatments. It’s recommended that individuals with TS receive thorough assessments from healthcare professionals who are experienced in treating both the core symptoms of TS and its associated comorbidities.

Causes

The exact cause of Tourette syndrome is not fully understood, but it is believed to result from a combination of genetic and environmental factors. Tic disorders appear to be ‘an inherited developmental disorder affecting the central nervous system’ (Chowdhury and Murphy, 2017). Although it is understood that TS is a genetic condition, the genetic cause of TS is complex. Twin studies have suggested a shared genetic etiology (cause) between TS and OCD but the relationship between TS and ADHD and/or ASD is less clear.

There appear to be structural brain differences and changes in the way the brain functions in the circuits of the brain (Felling and Singer, 2011). Brain studies show that certain structures in the brain and spinal cord are associated with tics. However, due to the variability of the severity and range of symptoms, different findings in adults and children, and the way behaviour and brain activity and structure are measured, research studies have not yet provided a single, clear explanation of how tics are produced in the brain (Chowdhury and Murphy, 2017). Different environmental factors may, in some cases, contribute to the onset or affect the severity of TS. These include obstetric problems such as complications during pregnancy or delivery, and premature, low birth weight children. (Brander et al 2018; Girgis and Pringsheim 2020). Tic disorders appear to be caused by the collective contributions of a number of genes (similar to the genetic contributions to height), not a single major gene (as in for instance cystic fibrosis).

It has also been suggested that abnormalities in certain brain regions or neural pathways may contribute to the development of Tourette syndrome. These abnormalities might involve the basal ganglia, which is responsible for movement control, and the insula, which appears to be involved in generation of premonitory phenomena and tics, as well as the supplementary motor area (SMA), which appears to be involved in tic suppression.

The neurotransmitter dopamine plays a role in regulating movement and behaviour. There is evidence to suggest that Tourette syndrome is associated with dysregulation of the dopamine systems in the brain. This may contribute to the occurrence of tics. Several of the most effective pharmacological treatments for tics inhibit dopamine transmission.

Some research suggests that immune system dysfunction might play a role in the development of Tourette syndrome. Autoimmune reactions or inflammation in the brain could potentially contribute to the occurrence of tics.

As yet the cause of Tourette Syndrome is not completely understood but it appears to be interplay between genetics, brain structure and function, and environmental factors.

Diagnosis and assessment

For TS to be diagnosed, multiple motor tics and at least one vocal tic must be present at some point during the course of at least 12 months. Symptoms usually present in children around the age of six years old, although formal diagnosis is not always immediate as the symptoms can go unidentified by both families and GPs and misattributed to allergies (e.g. sniffing) or a need for glasses (e.g. blinking or squinting).
TS can only be diagnosed by observing and evaluating symptoms. Rating scales are available to help with the assessment of tic severity. Some doctors may use an EEG, MRI, CT scan, or certain blood tests to rule out other conditions that might be confused with TS such as epilepsy, dystonia and Sydenham’s chorea. However, these assessments are not usually needed in patients with typical history and examination for TS and are not indicated in best practice guidelines.

The diagnosis and assessment of Tourette syndrome (TS) ideally involve a comprehensive evaluation conducted by healthcare professionals, often including neurologists, psychiatrists, and other specialists. The process involves gathering information about the individual’s medical history, symptoms, and their impact on daily life. Here are the key steps in diagnosing and assessing Tourette syndrome:

Clinical Evaluation
A healthcare professional, often a neurologist or psychiatrist, conducts a thorough clinical assessment. They gather information about the individual’s medical history, including any family history of tics or related disorders. The healthcare provider will ask about the onset, duration, frequency, and nature of tics. They may also inquire about any associated symptoms, such as obsessive-compulsive behaviours or attention difficulties.

Diagnostic Criteria
The diagnosis of Tourette syndrome is based on specific criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association. The primary criterion is the presence of multiple motor tics and at least one vocal tic, occurring many times a day or intermittently over a period of at least one year. Tics caused by other medical conditions are not diagnosed as TS.

Exclusion of Other Conditions
It’s essential to rule out other medical and neurological conditions that could be causing or contributing to the tics. Conditions such as other tic disorders, functional neurological symptoms, seizures, certain uncommon neurodegenerative conditions, or drug use need to be considered.

Psychological Assessment
Healthcare professionals often observe the individual over time to confirm the presence of tics and assess their frequency, severity, and impact on daily functioning. Input from family members, teachers, or caregivers is valuable to gain a comprehensive understanding of the individual’s symptoms and their impact on different settings. In some cases, psychological assessments might be conducted to evaluate for any coexisting conditions, such as attention-deficit/hyperactivity disorder (ADHD) or obsessive-compulsive disorder (OCD), which often occur alongside Tourette syndrome. Psychological and neuropsychological evaluation can also be helpful to identify and measure severity of comorbid conditions, and to support academic success. Since tics can change over time, a longitudinal assessment may be necessary to monitor the progression and fluctuations in symptoms.

It’s important to note that an accurate diagnosis of Tourette syndrome requires a thorough evaluation by qualified medical professionals. Once diagnosed, treatment options can be discussed, which may include behavioural therapies, medications, and supportive interventions to manage the symptoms and improve the individual’s quality of life.

While there is no cure for TS, treatments are available to manage the symptoms and improve the quality of life for individuals living with the condition. These treatments can include behavioural therapies, medications, and supportive interventions. Treatment and management approaches are often individualized based on the severity of tics and the impact they have on daily life. The goal is to improve quality of life and reduce distress caused by tics.

Medication

There is no specific drug that can stop all tics permanently. There are European Guidelines (Roessner et al 2022) based on systematic reviews and an NIHR Health Technology Assessment (National Institute for Health and Care Research) which looked at a whole group of studies (Hollis, et al 2016). For people with TS, medication can be helpful in reducing tics to a level that allows them to function in their everyday lives. The lowest effective dose should be used and medication should be carefully monitored. The spontaneous waxing and waning of tic severity over time should be kept in mind to prevent misattribution of improvement or worsening to a recent medication change. Medications can be prescribed to help manage the symptoms of Tourette syndrome (TS), especially when the tics are causing significant impairment in daily life or pain. It’s important to note that while medications can be beneficial, they may not completely eliminate tics and can come with potential side effects. The choice of medication depends on the severity of symptoms, the individual’s age, and their overall health. Here are some medications commonly used to treat TS:

Dopamine Receptor Blockers (Antipsychotics):

These medications are often used as first-line treatments for tics. They work by blocking dopamine receptors in the brain, which helps to reduce the severity and frequency of tics.

Common antipsychotics used for TS include:

• Haloperidol (Haldol)
• Pimozide (Orap)
• Risperidone (Risperdal)
• Aripiprazole (Abilify)
• Olanzapine (Zyprexa)

Alpha-2 Adrenergic Agonists

These medications are often used to manage tics as well as associated symptoms like ADHD or anxiety. Clonidine (Catapres) and guanfacine (Intuniv) are commonly prescribed alpha-2 agonists for TS.

Botulinum Toxin Injections

Botulinum toxin injections, commonly known as Botox, can be used to target specific muscle groups and reduce the severity of motor or phonic tics. This is particularly useful when one or two tics cause substantial discomfort or functional impairment.

Other medications

A number of clinical trials are investigating other treatments for tics. Some medications that are not primarily intended for TS may be used to manage specific symptoms or coexisting conditions. For example, topiramate or clonazepam can be used to treat tics, supported by some evidence. Stimulant medications like methylphenidate or amphetamine-based medications can be prescribed for individuals with TS who also have ADHD.

Psychological interventions

Behaviour therapy treatment for tics, specifically Comprehensive Behavioral Intervention for Tics (CBIT) and exposure and response prevention (ERP), have been recommended as first-line interventions for TS in treatment guidelines from the American Academy of Neurology (AAN) (Pringsheim et al. 2019) and the European Society for the Study of Tourette Syndrome (ESSTS) (Andren et al 2022). Recently, research has turned towards evaluating more broadly focused psychological treatments that attempt to equip children with the tools to live with Tourette Syndrome rather than just control their tics (Chowdhury and Murphy, 2017). The strongest evidence base to date for psychological interventions uses behavioural treatments that primarily focus on tic suppression. However, evidence is beginning to accrue for other approaches, such as mindfulness-based therapies.

Habit Reversal Therapy (HRT)

The best scientifically validated behavioural treatment is Habit Reversal Therapy (HRT), which has been researched since the 1970s.

Comprehensive Behavioural Intervention for Tics (CBiT)

More recently, HRT has been shown to be effective as part of a package alongside other elements of therapy, known as Comprehensive Behavioural Intervention for Tics (CBIT). CBIT is made up of different elements which include: Psychoeducation, Functional Analysis, HRT, Social Support and Reward System and Relaxation Training. HRT is a major component of CBIT. In this treatment the patient is made more aware of the premonitory urge and helped to implement a behaviour before the tics occur, to block the tic from being able to be performed. This is called a competing response.

Exposure and Response Prevention (ERP)

A fairly similar approach is exposure with response prevention (ERP). Patients practice suppressing their tics and don’t try to block them with a physical gesture but instead acclimatise to the premonitory urge and overtime resist it more effectively and habituate to the feeling. There is evidence to suggest that this approach is as effective as HRT. ERP may be best suited to people who have a range of very annoying tics or are of a young age. More recently, online delivery of HRT (or CBIT) has been shown to be effective, and can make these treatments accessible to a wider group of people with tics.

Myths around behavioural therapy

There are some myths surrounding behavioural therapy interventions, which can be dispelled. ‘Holding tics in’ will not cause them ‘to all burst out’ later on; research has found holding tics in, decreases tics generally over time. ‘Stopping one tic does not mean another one will get worse’ instead, research has found learning to control some tics makes all tics better (even the ones the patient may not have worked on). A common concern parents have is ‘will my child ‘catch’ other children’s tics?’ . In general no, but children may briefly pick up other tics during contact with other children with tics but they usually only last a couple of hours or days (Chowdhury and Murphy, 2017).  Even with this short-term issue, parents and children report it is definitely worth picking up a few temporary tics when meeting other families affected by TS, the benefits are very much worth it!

Individualized Treatment

The choice of medication should be tailored to the individual’s specific symptoms, needs, and any other medical conditions they may have. Treatment plans are often individualized to achieve the best outcomes.

Many people with TS are not distressed by their symptoms, and their function in social, educational and work settings is not impaired. Such patients may not need any treatment other than education about TS.

It’s important for individuals and their healthcare providers to carefully weigh the potential benefits of any treatment against its side effects and costs. Regular follow-up appointments are essential to monitor effectiveness, adjust dosage if needed, and manage any side effects.

Medication should ideally be part of a comprehensive treatment approach that may include behavioural therapies, psychoeducation, and supportive interventions. As TS symptoms can vary widely between individuals, treatment decisions should be made in collaboration with a knowledgeable healthcare provider who can provide guidance based on the individual’s unique circumstances.

Deep Brain Stimulation (DBS)

Deep Brain Stimulation (DBS) is a surgical treatment option that involves implanting electrodes into specific areas of the brain to deliver electrical impulses. DBS has been explored as a potential treatment for severe and refractory cases (non-responders) of Tourette syndrome (TS) when other treatment options have not provided sufficient relief. It’s important to note that DBS is considered a last-resort option and is not appropriate for most individuals with TS. DBS has shown promising results in reducing the severity and frequency of tics in some individuals with severe TS that has not responded well to other treatments. DBS is a surgical procedure, and like any surgery, it carries risks such as infection, bleeding, or adverse reactions to anaesthesia. It’s important for individuals and their medical teams to carefully consider the potential benefits, risks, and alternative treatments before deciding to proceed with DBS. A thorough assessment and informed decision-making process are crucial when considering this treatment option.

Cannabinoids

Cannabinoids are compounds found in the cannabis plant, and they have been explored as a potential treatment for various medical conditions, including Tourette syndrome (TS). However, the use of cannabinoids in TS is a complex and controversial topic, and the research in this area is still ongoing. Some studies suggest that cannabinoids, particularly delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), might have an impact on certain neurological symptoms, including tics. Some studies have reported potential benefits in reducing tics and associated symptoms, while others have not found significant improvements. Cannabinoids interact with the endocannabinoid system in the body, which plays a role in regulating various physiological processes, including mood, pain, and movement. The use of cannabinoids for medical purposes is still not well-regulated, and there is a lack of standardized dosing and administration guidelines. Variability in the composition and potency of cannabis products can make it challenging to determine the optimal treatment approach. Cannabinoid use, especially THC-containing products, can be associated with potential side effects such as impaired cognitive function, anxiety, and mood changes, and the risks appear to be higher for adolescents than for adults.

Recent research data from a large multi-centre project CANNA-TICS suggest that cannabis-based medicines can have a role in the treatment of patients with tic disorders such as Tourette Syndrome, which could lead to an improvement of tics, comorbidities, and quality of life (Müller-Vahl et al 2023).

However, more research is needed to establish their safety, efficacy, and appropriate use. Individuals with TS who are considering cannabinoid-based treatments should have a thorough discussion with their healthcare provider, weigh potential benefits against risks, and explore alternative treatment options that have a stronger evidence base. Medical cannabinoids are not yet a proven treatment for Tourette syndrome, although there is ongoing research. In the NHS they can be prescribed only with a special application in the case of Tourettes.

TMS

TMS stands for Transcranial magnetic stimulation. ‘This is a non-invasive method of brain stimulation in which an electric coil is used to induce a magnetic field over the scalp. This induces circular electrical (eddy) currents in the brain that in turn cause stimulation of neurons and muscle activity. Repeated stimulation with short bursts of high-frequency stimulation has been applied for the treatment of movement disorders in humans’ (Hollis et al, 2016).

TMS is one particular type of non-invasive brain stimulation (NIBS); research findings suggest that NIBS may form the basis for new non-drug treatments for Tourette syndrome that are safe and effective in reducing tics. They have been used with some success in other movement disorders such as Parkinson’s Disease. NIBS is being used in the UK to treat a number of conditions such as depression, chronic pain, and to promote recovery of function after stroke, however NIBS is not yet being used to treat Tourette syndrome. More research evidence would be needed before this could be considered as a potential treatment.

TMS has been explored as a potential treatment for various neurological and neuropsychiatric conditions, including Tourette syndrome (TS). TMS works by inducing electrical currents in the brain. Depending on the parameters of stimulation, it can either enhance or inhibit neural activity in the targeted brain area. The goal of using TMS for TS is to modulate the neural circuits responsible for the generation of tics and other TS symptoms. Some studies have reported a large reduction in tic frequency and tic intensity in individuals with TS.

TMS is generally considered safe, but there can be side effects such as mild discomfort at the stimulation site or mild headache. The long-term effects and optimal treatment parameters for TMS in TS are not yet fully understood. Availability of TMS may be limited, and it may not be available through their healthcare provider.

Different research groups have found median nerve stimulation (MNS) to improve tic frequency and intensity with minimal side effects (Iverson et al 2023). This is exciting as development and trials of ‘a therapeutic device suitable for use outside of the clinic to suppress tics and PU in TS’ are currently underway in 2023 (Morera et al 2020).

TMS is generally considered safe, but there can be side effects such as mild discomfort at the stimulation site or mild headache. The long-term effects and optimal treatment parameters for TMS in TS are not yet fully understood. Availability of TMS may be limited, and it may not be available through their healthcare provider.

Botox

In addition to the pharmacological treatment presented, the EU clinical guidelines (Roessner et al 2011) also put forward the case that there is increasing evidence ‘for the efficacy of botulinum toxin injections to treat persistent well-localized (non-complex) motor and, sometimes, vocal tics by temporarily weakening the associated muscles’. There can be adverse reactions including temporary soreness and mild muscle weakness.

Exercise

There are some research evidence that there can be beneficial effects of exercise on TS symptomatology as well as beneficial impacts on self-reported anxiety and mood levels (Reilly, Grant,  Bennett, Murphy T and Heyman (2019).

Gut microbiota

Emerging research has shown a potential connection between gut microbiota and various neurological and neuropsychiatric conditions, including Tourette syndrome (TS). The gut-brain connection, often referred to as the gut-brain axis, suggests that the gut microbiota (the community of microorganisms living in the digestive tract) might influence brain function and behaviour through complex communication pathways. Imbalances in gut microbiota, known as dysbiosis, have been linked to various neurological and neuropsychiatric conditions, including anxiety, depression, and possibly Tourette syndrome. Some studies have reported differences in the gut microbiota composition of individuals with TS compared to those without the disorder. While research is still in its early stages, there is interest in exploring whether interventions that target gut microbiota, such as dietary changes or probiotics, could have a positive impact on neurological and neuropsychiatric conditions, including TS. It’s important to note that the relationship between gut microbiota and Tourette syndrome is complex, and the exact mechanisms are not fully understood. Research is ongoing to elucidate the connections and potential therapeutic implications.

Traditional Chinese Herbal Medicine

Traditional Chinese Herbal Medicines are being used currently being used to treat TS in countries such as China, with more journal articles on this subject being published. Some researchers support the use of the 5-Lin granule in treating tic disorders and there is a multisite clinical trial planed in the US. However, this topic of research is an emerging area of research at the present time (Wang et al 2021).

Median nerve stimulation

Different research groups have found median nerve stimulation (MNS) to improve tic frequency and intensity with minimal side effects (Iverson et al 2023; Morera Maiquez et al 2023). This is exciting as development and trials of ‘a therapeutic device suitable for use outside of the clinic to suppress tics and PU in TS’ are currently underway in 2023 (Morera et al 2020).

Other research areas

There are some not-yet validated treatments which do not have an established research evidence base, but which some people report having found including neurofeedback, acupuncture, dental splints, music, nutritional supplements. Iverson and Black (2022) argue that other variables ‘such as social media exposure and dietary habits have received only minimal research attention and would benefit from additional study’. They suggest that ‘understanding the impact of these environmental and internal influences provides an opportunity to improve behavioural treatments for Tourette Syndrome or Chronic Tic Disorder and to improve the lives of those living with these conditions’.

PANDAS

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) is a controversial and not widely accepted subset of paediatric neuropsychiatric disorders. It proposes that certain infections, often streptococcal infections like strep throat, can trigger sudden and severe onset of neuropsychiatric symptoms in children. These symptoms can include obsessive-compulsive behaviours (OCD), tics, anxiety, and other behavioural changes. This is a controversial condition with, at present, little research evidence to back up a link to a streptococcal infection but ‘it is recognised that there is a subgroup of children who present with sudden-onset acute OCD with or without tics’ (Chowdhury and Murphy, 2017). There is debate within the medical community about the existence and validity of PANDAS as a distinct diagnostic entity (Gilbert et al 2019) Some experts believe that while streptococcal infections can exacerbate symptoms in children with pre-existing neuropsychiatric conditions like Tourette syndrome (TS) or OCD, the concept of PANDAS as a separate syndrome is not yet fully supported by scientific evidence. PANDAS centres on the hypothesis that infections trigger an immune response that leads to neurological symptoms. However, research findings have been inconsistent; the older studies were often small and lacking in rigorous methodology, and newer, larger, prospective studies have not supported this hypothesis (Hartmann et al 2022). The EMTICS study and others did not find Group A Streptococcal (GAS) exposures as contributing factors for tic exacerbations in children with CTD. Specific work-up or active management of GAS infections was suggested as being unlikely to help tics in chronic tic disorders and is therefore not suggested. These results were the same as previous studies (Gilbert, 2019).

It’s important to consult with qualified healthcare professionals when considering a diagnosis and treatment for neuropsychiatric symptoms in children. Treating tics or OCD with antibiotic or immune-directed medications is considered experimental, and before considering them, one must recognize that there are treatments of proven efficacy as described above, including behavioural therapies of demonstrated safety.

Functional tic‐like behaviors (FTLBs)

During the (COVID-19) pandemic in 2020, there was an increase in presentations of sudden and new onset tics particularly affecting teenage girls, at first media outlets reported this as ‘sudden onset Tourette Syndrome’. However as clinical data was gathered it became apparent that these cases were functional tic‐like behaviors (FTLBs) related to functional neurological disorder (FND). It can bee difficult to distinguish FTLBs from tics typical of Tourette Syndrome, but papers exist now that provide evidence showing different age of onset and other characteristics which can help classify them correctly (Pringsheim et al 2023; Ludlow et al 2023).  Reporting of FTLBs since the end of the pandemic has reduced greatly; however, it has been suggested that there may be patients with comorbid functional tic‐like behaviors (FTB) with Tourette syndrome (TS). Muller-Vahl et al (2023) even suggest ‘that FTB is a common comorbidity in TS, similar to functional overlay in other movement disorders and epilepsy’.

Research into genetics, brain imaging, behavioural science, neuroscience and neuropathology is helping us to make progress towards understanding the basis of TS.

ORBIT

It can be very difficult for people with tics to get access to behavioural therapy for tics. This is because there are only a small number of therapists who offer this treatment to children with tics in the UK. The ORBIT (short for ‘Online Remote Behavioural Treatment for Tics’) study group has been working towards providing behavioural treatments online (talking therapies that focus on changing a person’s behaviours and thoughts) which can be as effective as medication for tics and Tourette syndrome. Hollis et al (2021) found that ‘ERP is an effective behavioural therapy for tics’. Also excitingly the study group suggest that this will improve access to behavioural therapy for tics in children and adolescents with ‘online ERP with minimal therapist contact time represent(ing) an efficient public mental health approach’ to treatment of tics. Hollis et all 2021 used a platform for therapist-supported, internet-delivered ERP (this was piloted via a research project in Sweden BIP TIC ERP program (Andren et al 2019).  Andren et al (2022) found that both therapist-supported, internet-delivered ERP and therapist-supported, internet-delivered psychoeducation internet-delivered interventions were helpful for young individuals with tic disorders. The momentum of this continues with the creation of the ‘ORBIT-UK’ study in 2023. This is a NIHR funded research project which aims to develop ORBIT on a UK-based, regulatory-approved platform. It aims to define the service specification and pathway, test the usability and acceptability of the platform as well as developing a commercialisation and NHS adoption strategy leading to a NHS-ready clinical product for commercial adoption and NHS commissioning in the UK.

INTEND

In many regions of England, children and young people with tics and Tourette Syndrome are unable to access healthcare services for their tics. They experience long delays before they are given a diagnosis and, even once a diagnosis is given, they may be unable to access treatment or other support. The ImproviNg Tic Services in EnglaND (INTEND) research study will explore current service provision for tics and Tourettes in England. This is a NIHR-funded project led by Dr Maddie Groom at the University of Nottingham launched on November 1st, 2023. Working with experts throughout England to develop a recommended care pathway for the referral, assessment and treatment of tics. There will be consultation with commissioners and transformation managers in a number of NHS Trusts in England to gather their feedback on these recommendations. We will then seek further funding to finalise the recommendations and accompanying guidelines and evaluate their implementation in clinical services. To read more about this please visit ImproviNg Tic Services in EnglaND (INTEND) study – Institute of Mental Health

SATURN

Another NIHR funded research study underway in the UK is called Stimulant Medication for ADHD and Tics – Understanding Response versus Non-stimulants (SATURN). This is a randomised trial of the clinical and cost-effectiveness of methylphenidate versus Guanfacine for ADHD in children and young people with a co-existing tic disorder SATURN. The TACT study was a similar previous trial with clonidine in place of guanfacine (Tourette’s Syndrome Study Group, 2002).

Books

Murphy, T., Chowdhury, U. (2017) Tic Disorders: A Guide for Parents and Professionals. Jessica Kingsley Publishers

Martino, D.  and Leckman, J. (2022). Tourette Syndrome, 2 edn Oxford Academic Press.

Verdellen, C., van de Griendt, J., Kriens, S. and van Oostrum, I. (2011) Tics: Therapist Manual. Amsterdam: Boom Publishers.

Woods. D., Piacentini, J., Chang, S.W., Deckersbach, T. et al. (2008) Managing Tourette Syndrome: A Behavioural Intervention for Children and Adults.  Therapist Guide (Treatments That Work). Oxford University Press.

McKinley, D (2009) Nix Your Tics! Eliminating Unwanted Tic Symptoms: A How-To Guide for Young People J Can Acad Child Adolesc Psychiatry;18(4) 357-358. PMCID: PMC2765394.

Murphy, T. and Millar, D. (2019) The Tourettes Survival Kit: Tools for Young Adults with Tics.. Jessica Kingsley Publishers

 

Websites

Tourettes Action
Supports people with Tourette Syndrome, and those who work with them, and funds research into treatment and diagnosis.

OCD Action
Provide support and information to anybody affected by OCD, work to raise awareness of the disorder amongst the public and front-line healthcare workers, and strive to secure a better deal for people with OCD.

ADHD Foundation Neurodiversity Charity
The ADHD Foundation works in partnership with individuals, families, and professionals to improve the well-being, and life chances of people living with ADHD, ASD and related learning difficulties.

Anxiety UK
Works to relieve and support those living with anxiety and anxiety-based depression by providing information, support and understanding via an extensive range of services.

Tourette Scotland – a charity working exclusively in Scotland to support people living with TS

TTAG – Tics and Tourette Across the Globe is a global umbrella association representing Tics and Tourette Syndrome associations

ESSTS European Society for the Study of Tourette Syndrome

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