This chapter provides a brief overview of the endocrine system by describing the different types of hormones and the organs involved in their production. The functions of the main hormones are summarised and the multifaceted relationships between the endocrine system and the nervous systems are discussed. Hormones should not be seen as isolated substances, but as active components of complex pathways with dynamic interactions and signalling mechanisms. A more in-depth understanding of hormonal pathways has led to the emergence of psychoneuroendocrinology, a modern clinical discipline that investigates the reciprocal influences between brain, endocrine system, and psychological processes. Imbalances in hormonal levels can result in pathological changes in both the brain and the body. Specific pathologic responses, such as general adaptation syndrome and allostatic overload, have been described and linked to paradigmatic examples of endocrine imbalances. A neuroendocrinological perspective on psychiatry provides valuable insights about the multiple contributions of hormones to the mechanisms underlying psychopathology.

Neuropsychiatry has a long and fascinating history as a discipline at the interface between neurology and psychiatry that combines clinical observations with modern investigational techniques. Historically, organic psychiatry has focused on clinical syndromes with regional connections affecting the four cortical lobes and the corpus callosum. Behavioural neurology has developed from early observations of classical neurocognitive syndromes, including aphasia, alexia, apraxia, agnosia and Gerstmann syndrome. A number of common neurological conditions often present with specific psychiatric symptoms: traumatic brain injury, cerebrovascular disease, brain tumours, epilepsy, movement disorders, infectious diseases and autoimmune neurological disorders such as multiple sclerosis, systemic lupus erythematosus and autoimmune encephalopathies. The differential diagnosis between delirium, dementia and pseudodementia can pose significant challenges. Finally, several toxic, metabolic and endocrine disorders can have clinically relevant neuropsychiatric manifestations.

Tourette syndrome is a neurodevelopmental condition characterized by multiple tics. A tic is a sudden, rapid, repetitive, non-rhythmic movement (e.g. eye blinking) or vocalization (e.g. throat clearing). Tics are often described as semi-voluntary or ‘unvoluntary’, as, strictly speaking, they are neither voluntary nor involuntary, but may be experienced as a voluntary response to an unwanted distressing sensation called ‘premonitory urge’. Premonitory urges are physical ‘build-up’ sensations to perform specific tics, which are perceived as suppressible yet irresistible, similar to the need to sneeze or scratch an itch. Patients often describe the need to tic as the mounting of inner tension, localized either to the body region where the tic is about to occur or throughout the body. Tic expression is typically associated with a transient sensation of relief.

The main pharmacodynamic and pharmacokinetic properties of Metoclopramide (Figure 6.1) are summarized in Table 6.1. Dose is 10 mg daily for 14 days, then increased by 10 mg every 14 days; usual maintenance 30 mg daily in three divided doses (maximum dose 60 mg daily). The main clinical indications of Metoclopramide in addition to tics are listed in Table 6.3.

The assessment and quantification of tics can pose considerable difficulties because of a number of factors, including the spontaneous fluctuations of tic severity and the tendency of patients to suppress their tics, especially when in the consultation room with the clinician. It is therefore advisable to supplement direct observation and clinical interviewing (including historical and external information whenever available) with the use of psychometric instruments validated in patients with Tourette syndrome. Information can be obtained from patients or from informants such as parents and teachers, through questionnaire constructs. For Tourette syndrome, most available instruments are parent- and/or teacher-rated questionnaires in childhood and self-report scales in adolescence and adulthood (Table 2.1).

The ‘maladie des tics’ is currently associated with the name of the French physician who published its first scientific description, Georges Gilles de la Tourette. What is currently known as Tourette syndrome should be more appropriately referred to as ‘Gilles de la Tourette syndrome’ – after the full surname of the French doctor who published the first comprehensive description of this complex tic disorder. The 1885 article by Gilles de la Tourette featured a case series of nine patients sharing a triad of symptoms encompassing motor/vocal tics (involuntary movements and vocalizations), echolalia (involuntary repetition of others’ words) and coprolalia (involuntary swearing). The current definition of Tourette syndrome as a complex chronic tic disorder focuses on the presence of multiple motor tics plus at least one vocal tic, whereas complex vocal tics such as echolalia and coprolalia are not included in the diagnostic criteria. However, this is only the most recent part of a long history that dates back to ancient times.

Over the last few decades, evidence-based medicine has established itself as a new paradigm for teaching and practising clinical medicine. Double-blind randomized controlled trials and high-quality observational studies have gradually replaced tradition, anecdote, and theoretical reasoning from basic sciences as sources of evidence to complement clinical expertise in order to fulfil patients’ needs. The development of disease-specific guidelines has arguably contributed to the process of making clinical practice more scientific and empirically grounded, resulting in safer, more consistent and more cost effective care. However the evidence-based paradigm has received criticism based on the argument that the emphasis on experimental evidence could devalue basic sciences and the tacit knowledge that accumulates with clinical experience. Moreover, it has been argued that the evidence-based movement arose primarily from a desire to standardize care, rather than individualizing it. Practising medicine according to the standards set out by guidelines could be seen as antithetical to practising according to clinical judgement: standardization can only identify best practices for an ‘average’ patient under ‘average’ conditions, whereas clinical judgement is by definition personal and seeks to decide what is best for a ‘specific’ patient at a ‘specific’ time.

In order to systematically examine treatment practices in Tourette syndrome across Europe-based clinicians, all ESSTS members actively prescribing for paediatric and/or adult patients with Tourette syndrome were invited to complete an online questionnaire covering pharmacological treatment of five symptom domains: tics, attention-deficit and hyperactivity symptoms, obsessive-compulsive symptoms, anxiety and depression. The results the first large-scale survey on prescribing habits for the pharmacological management of Tourette syndrome in Europe were published in the European Journal of Paediatric Neurology in 2012.

The main pharmacodynamic and pharmacokinetic properties of Clonidine (Figure 5.1) are summarized in Table 5.1. Dose is 0.025 mg daily for 14 days, then increased by 0.025 mg every 14 days; usual maintenance 0.1–0.4 mg daily in two to three divided doses (maximum dose 1.2 mg daily). The main clinical indications of Clonidine in addition to tics are listed in Table 5.3. Caution is warranted when using Clonidine in patients with the conditions listed in Table 5.4.

The main pharmacodynamic and pharmacokinetic properties of Fluphenazine (Figure 3.1) are summarized in Table 3.1. Dose is 1–2.5 mg daily for 14 days, then increased by 1–2.5 mg every 14 days; usual maintenance 10–20 mg daily in two divided doses (maximum dose 40 mg daily). The main clinical indications of Fluphenazine in addition to tics are listed in Table 3.3.