Drug-induced tics: An observational postmarketing study.

OBJECTIVES: While drug-induced tics have been described, in particular with neuroleptics, psychostimulants, or anti-epileptics, the strength and the direction of these associations are still debated. The aim of this study was to investigate the association between tics and drug exposure through a two-step analysis in two pharmacovigilance databases. METHODS: We first performed a descriptive clinical analysis of cases registered in the French pharmacovigilance database (FPVD) from January 1985 to December 2018. We then performed a disproportionality analysis in VigiBase®, the WHO pharmacovigilance database, from January 1967 to June 2019, through the calculation of reporting odds ratio (ROR). RESULTS: The drugs most frequently associated with tics in the FPVD were methylphenidate, lamotrigine, montelukast, tramadol, mirtazapine, venlafaxine, aripiprazole, and risperidone. In VigiBase®, we found a significant ROR with methylphenidate (ROR 37.54, 95% confidence interval [CI] 34.81-40.48), montelukast (ROR 12.18, 95% CI 10.29-14.41), aripiprazole (ROR 7.40, 95% CI 6.35-8.62), risperidone (ROR 4.40, 95% CI 3.72-5.21), and venlafaxine (ROR 1.52, 95% CI 1.14-2.03). CONCLUSION: This postmarketing study confirmed a potential harmful association with methylphenidate (the highest association, as expected), aripiprazole, risperidone, lamotrigine, and venlafaxine and, interestingly, found a strong signal with montelukast, which, to our knowledge, had never been published before.

Global dysrhythmia of cerebro-basal ganglia-cerebellar networks underlies motor tics following striatal disinhibition.

Motor tics, a cardinal symptom of Tourette syndrome (TS), are hypothesized to arise from abnormalities within cerebro-basal ganglia circuits. Yet noninvasive neuroimaging of TS has previously identified robust activation in the cerebellum. To date, electrophysiological properties of cerebellar activation and its role in basal ganglia-mediated tic expression remain unknown. We performed multisite, multielectrode recordings of single-unit activity and local field potentials from the cerebellum, basal ganglia, and primary motor cortex using a pharmacologic monkey model of motor tics/TS. Following microinjections of bicuculline into the sensorimotor putamen, periodic tics occurred predominantly in the orofacial region, and a sizable number of cerebellar neurons showed phasic changes in activity associated with tic episodes. Specifically, 64% of the recorded cerebellar cortex neurons exhibited increases in activity, and 85% of the dentate nucleus neurons displayed excitatory, inhibitory, or multiphasic responses. Critically, abnormal discharges of cerebellar cortex neurons and excitatory-type dentate neurons mostly preceded behavioral tic onset, indicating their central origins. Latencies of pathological activity in the cerebellum and primary motor cortex substantially overlapped, suggesting that aberrant signals may be traveling along divergent pathways to these structures from the basal ganglia. Furthermore, the occurrence of tic movement was most closely associated with local field potential spikes in the cerebellum and primary motor cortex, implying that these structures may function as a gate to release overt tic movements. These findings indicate that tic-generating networks in basal ganglia mediated tic disorders extend beyond classical cerebro-basal ganglia circuits, leading to global network dysrhythmia including cerebellar circuits.

Antidepressant-like effects of a water-soluble extract from the culture medium of Ganoderma lucidum mycelia in rats.

BACKGROUND: Ganoderma lucidum is a popular medicinal mushroom used for promoting health and longevity in Asian countries. Previously, we reported that a water-soluble extract from a culture medium of Ganoderma lucidum mycelia (MAK) exerts antioxidative and cerebroprotective effects against ischemia-reperfusion injury in vivo. Here, we evaluated the antidepressant and anxiolytic activities of MAK in rats. METHODS: MAK (0.3 or 1 g/kg, p.o.) was administered in the experimental animals 60 min before the forced swimming, open-field, elevated plus-maze, contextual fear-conditioning, and head twitch tests. Additionally, the mechanisms involved in the antidepressant-like action of MAK were investigated by the serotonin precursor 5-hydroxy-L-tryptophan (5-HTP)- or 5-HT2A agonist (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI)-induced head twitch responses. RESULTS: Treatment with MAK (1 g/kg) exhibited antidepressant-like effects in the forced swimming test, attenuated freezing behavior in the contextual fear-conditioning test, and decreased the number of head twitches induced by DOI, but not with 5-HTP. No significant response was observed in locomotion or anxiety-like behavior, when the animals were evaluated in the open-field or elevated plus-maze test, respectively. CONCLUSIONS: These data suggest that MAK has antidepressant-like potential, which is most likely due to the antagonism of 5-HT2A receptors, and possesses anxiolytic-like effects toward memory-dependent and/or stress-induced anxiety in rats.

Tetrahydrocannabinol and Cannabidiol in Tourette Syndrome.

BACKGROUND: Tourette syndrome is characterized by chronic motor and vocal tics. There is preliminary evidence of benefit from cannabis products containing Δ9-tetrahydrocannabinol (THC) and that coadministration of cannabidiol (CBD) improves the side-effect profile and safety. METHODS: In this double-blind, crossover trial, participants with severe Tourette syndrome were randomly assigned to a 6-week treatment period with escalating doses of an oral oil containing 5 mg/ml of THC and 5 mg/ml of CBD, followed by a 6-week course of placebo, or vice versa, separated by a 4-week washout period. The primary outcome was the total tic score on the Yale Global Tic Severity Scale (YGTSS; range, 0 to 50 [higher scores indicate greater severity of symptoms]). Secondary outcomes included video-based assessment of tics, global impairment, anxiety, depression, and obsessive-compulsive symptoms. Outcomes were correlated with plasma levels of cannabinoid metabolites. A computerized cognitive battery was administered at the beginning and the end of each treatment period. RESULTS: Overall, 22 participants (eight female participants) were enrolled. Reduction in total tic score (at week 6 relative to baseline) as measured by the YGTSS was 8.9 (±7.6) in the active group and 2.5 (±8.5) in the placebo group. In a linear mixed-effects model, there was a significant interaction of treatment (active/placebo) and visit number on tic score (coefficient = −2.28; 95% confidence interval, −3.96 to −0.60; P=0.008), indicating a greater decrease (improvement) in tics under active treatment. There was a correlation between plasma 11-carboxy-tetrahydrocannabinol levels and the primary outcome, which was attenuated after exclusion of an outlier. The most common adverse effect in the placebo period was headache (n=7); in the active treatment period, it was cognitive difficulties, including slowed mentation, memory lapses, and poor concentration (n=8). CONCLUSIONS: In severe Tourette syndrome, treatment with THC and CBD reduced tics and may reduce impairment due to tics, anxiety, and obsessive-compulsive disorder; although in some participants this was associated with slowed mentation, memory lapses, and poor concentration. (Funded by the Wesley Medical Research Institute, Brisbane, and the Lambert Initiative for Cannabinoid Therapeutics, a philanthropically-funded research organization at the University of Sydney, Australia; Australian and New Zealand Clinical Trials Registry number, ACTRN12618000545268.)

Sertraline-Induced Tics: A Case Report and Narrative Review.

This brief report describes the case of a 16-year-old girl who was commenced on sertraline for anxiety and depression, and subsequently developed severe and debilitating motor tics. Cessation of sertraline was associated with the resolution of tics; after this, paroxetine was trialled and well tolerated with good response of targeted symptoms and without re-emergence of tics. A narrative literature review yielded a retrospective observational study and eight single case reports on selective serotonin receptor inhibitor-induced motor tics (three in adolescents and five in adults). Tics are not commonly considered as a side-effect of SSRIs. This case report is novel is several aspects: the tics emergence was immediate whereas previous cases were delayed; the tics symptoms were measured and quantified by a validated scale; a dose-response relationship was observed; to our knowledge, our case was the first adolescent female reported; and finally, paroxetine was well-tolerated as a substitute, although it is unclear whether the observed tics-sparing effect is co-incidental, ideocratic or can be replicated.

Ecopipam for Tourette Syndrome: A Randomized Trial.

BACKGROUND AND OBJECTIVES: All US Food and Drug Administration-approved medications for Tourette syndrome are antipsychotics, and their use is limited by the risk of weight gain, metabolic changes, and drug-induced movement disorders. Several small trials suggest that ecopipam, a first-in-class, selective dopamine 1 receptor antagonist, reduces tics with a low risk for these adverse events. This trial sought to further evaluate the efficacy, safety, and tolerability of ecopipam in children and adolescents with moderate to severe Tourette syndrome. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled, phase 2b trial. Subjects aged ≥6 to <18 years with a baseline Yale Global Tic Severity Score Total Tic Score of ≥20 were randomly assigned 1:1 to ecopipam (n = 76) or placebo (n = 77). The primary endpoint was mean change over 12 weeks in the Yale Global Tic Severity Score Total Tic Score. The Clinical Global Impression of Tourette Syndrome Severity was the secondary endpoint. Safety and tolerability were evaluated at each study visit. RESULTS: Total tic scores were significantly reduced from baseline to 12 weeks in the ecopipam group compared with placebo (least squares mean differences -3.44, 95% confidence interval -6.09 to -0.79, P = .01). Improvement in Clinical Global Impression of Tourette Syndrome Severity was also greater in the ecopipam group (P = .03). More weight gain was seen in subjects assigned to placebo. No metabolic or electrocardiogram changes were identified. Headache (15.8%), insomnia (14.5%), fatigue (7.9%), and somnolence (7.9%) were the most common adverse events. CONCLUSIONS: Among children and adolescents with TS, ecopipam reduces tics to a greater extent than placebo, without observable evidence of common antipsychotic-associated side effects.

Efficacy of clonidine in the treatment of children with tic disorder co-morbid with attention deficit hyperactivity disorder.

OBJECTIVE: The current research was designed to assess the efficacy of clonidine in the treatment of children with tic disorder co-morbid with attention deficit hyperactivity disorder. PATIENTS AND METHODS: A total of 154 children with tic disorder co-morbid with attention deficit hyperactivity disorder admitted to our hospital from July 2019 to July 2022 were recruited and assigned to receive either methylphenidate hydrochloride plus haloperidol (observation group) or clonidine (experimental group), with 77 cases in each group. Outcome measures included clinical efficacy, Yale Global Tic Severity Scale (YGTSS) scores, Conners Parent Symptom Questionnaire (PSQ) scores, and adverse events. RESULTS: Clonidine was associated with markedly higher clinical efficacy vs. methylphenidate hydrochloride plus haloperidol (p<0.05). Clonidine offered more significant mitigation of the tic disorder vs. methylphenidate hydrochloride plus haloperidol, as evinced by the lower kinetic tic scores, vocal tic scores, and total scores (p<0.05). Children exhibited markedly milder tic symptoms after clonidine monotherapy vs. those with dual therapy of methylphenidate hydrochloride and haloperidol, suggested by the lower scores of character problems, learning problems, psychosomatic disorders, hyperactivity/impulsivity, anxiety index, and hyperactivity index (p<0.05). Clonidine features a higher safety profile than methylphenidate hydrochloride plus haloperidol by reducing the incidence of adverse events (p<0.05). CONCLUSIONS: Clonidine effectively alleviates tic symptoms, reduces attention deficit and hyperactivity/impulsivity in children with tic disorder co-morbid attention deficit hyperactivity disorder, and features a high safety profile.

Thimerosal exposure in early life and neuropsychological outcomes 7-10 years later.

OBJECTIVE: The authors used a public use data set to investigate associations between the receipt of thimerosal-containing vaccines and immune globulins early in life and neuropsychological outcomes assessed at 7-10 years. METHODS: The data were originally created by evaluating 1,047 children ages 7-10 years and their biological mothers. This study developed seven latent neuropsychological factors and regressed them on a comprehensive set of covariates and thimerosal exposure variables. RESULTS: The authors found no statistically significant associations between thimerosal exposure from vaccines early in life and six of the seven latent constructs. There was a small, but statistically significant association between early thimerosal exposure and the presence of tics in boys. CONCLUSIONS: This finding should be interpreted with caution due to limitations in the measurement of tics and the limited biological plausibility regarding a causal relationship.

Carbamazepine-induced non-epileptic myoclonus and tic-like movements.

Carbamazepine-induced abnormal movements have been reported in children and adult patients, and both non-epileptic myoclonus and tic-like movements have been reported in the same patient. Although a pathogenetic mechanism underlying carbamazepine-induced epileptic negative myoclonus has been proposed, a causative role of carbamazepine for positive myoclonus has not been fully identified. Here, we describe the video-documented case of an adult patient with non-epileptic myoclonus and tic-like movements persisting for 21 years, which appeared after he started carbamazepine treatment at 10 years of age. [Published with videosequences].

[Study on the toxic reaction induced by single dose of qingkailing injection].

OBJECTIVE: To study the toxic reaction induced by Qingkailing Injection. METHODS: Kunming mice were injected single dose of Qingkailing Injection via tail vein and observed for 14 days to test the toxic reaction of the drug. According to Chinese Pharmacopoeia, hemolysis tests were conducted on the injections of different lots and each ingredient of the injection. RESULTS: Toxic reaction induced by single dose of injection--with dose increasing,mice quickly showed different responses such as hypodynamia, convulsion, syncope and even death after injection. In the high dose group, blood routine detection showed that mice have lower counts of RBC, WBC and lower content of hemoglobin; The pulmonary pathological sections of dead mice showed significant hyperemia. And there were no significant difference in the contents of serum electrolyte (K+, Na+, Ca2+) between normal saline control group and Qingkailing injection group. Hemolysis test in vitro--Honeysuckle extraction (significantly) and gardenia extraction which were components of Qing-kailing injection caused hemolysis in certain dose; While gardenia, pearl shell and isatis root extraction caused RBC agglutination. With higher concentration, the Qingkailing injections of different lot caused different degree of hemolysis. There was no significant difference in the hemolysis test in vitro between the group of Balb/C mice which were sensitized by Qingkailing injection or not. CONCLUSION: In clinical practice some adverse reactions induced by Qingkailing injection occurred concomitantly with acute hemolysis within vessels, which might be caused by honeysuckle and gardenia. And the hemolysis was independent of allergy.

The Recurrence of Motor Tics Mediated by Oral Prednisolone Use in Autistic Children: A Case Report.

OBJECTIVES: This study aimed to report motor tics worsening by prednisolone acute treatment, despite the use of aripiprazole and clonidine. It was also aimed to discuss the mechanisms involved in neuropsychiatric adverse effects with the use of corticosteroids. METHODS: It was reported a 7-year-old boy patient with a history of autism spectrum disorder and motor tics. He has remitted motor tics with an association between aripiprazole and clonidine. However, was registered motor tics' recurrence with acute use of prednisolone. CONCLUSIONS: The neuropsychiatric adverse effects mediated by corticosteroid use are low explored, mainly in pediatric clinical practice. The prednisolone prescription is widespread in childhood and, considering some vulnerable conditions to this type of adverse effects, is imperative.

Lactobacillus plantarum PS128 ameliorates 2,5-Dimethoxy-4-iodoamphetamine-induced tic-like behaviors via its influences on the microbiota-gut-brain-axis.

We previously reported a novel psychobiotic strain of Lactobacillus plantarum PS128 (PS128) which could ameliorate anxiety-like& depression-like behaviors and modulate cerebral dopamine (DA) and serotonin (5-HT) in mice. Here, we examine the possibility of using PS128 administration to improve tic-like behaviors by using a 5-HT2A and 5-HT2C receptor agonist 2,5-Dimethoxy-4-iodoamphetamine (DOI). PS128 was orally administered to male Wistar rat for 2 weeks before two daily DOI injections. We recorded the behaviors immediately after the second DOI injection and compared the results with control and haloperidol treatment groups. PS128 significantly reduced tic-like behaviors and pre-pulse inhibition deficit in a threshold-dose of 109 CFU per day. Brain tissue analysis showed that DOI induced abnormal DA efflux in the striatum and prefrontal cortex, while PS128 ingestion improved DA metabolism and increased norepinephrine (NE) levels in these two regions. In addition, PS128 ingestion increased DA transporter and ß-arrestin expressions and decreased DOI-induced phosphorylation of DA and cAMP regulated phosphoprotein of molecular weight 32 kDa (DARPP-32) at Thr34 and extracellular regulated protein kinases (ERK). PS128 ingestion also modulated peripheral 5-HT levels and shaped the cecal microbiota composition, which helps to alleviate DOI-induced dysbiosis. These results suggested that PS128 ameliorated DOI-induced tic-like hyper-active behaviors via stabilizing cerebral dopaminergic pathways through its modulation of host's microbiota-gut-brain axis. Thus, we believe there are potentials for utilizing psychobiotics to improve syndromes caused by DA dysregulation in DA-related neurological disorders and movement disorders such as Tourette syndrome.

Long-term safety of stimulant medications used to treat children with ADHD.

Attention-deficit/hyperactivity disorder (ADHD) is a common mental health condition that affects children, adolescents, and adults. Because it is a chronic condition and typically requires effective treatment for several years or more, information on the benefits and risks of long-term pharmacotherapy for ADHD is vital to clinicians. This article reviews the emerging literature on the safety of long-term stimulant medications in ADHD-the most commonly prescribed medications for this condition. Common side effects, including cardiovascular effects, growth effects, and tics, are discussed, as well as treatment of children younger than age 6 and evidence of carcinogenic and reproductive effects.

[Side effects of methylphenidate in children and the young]. / Efectos secundarios del metilfenidato en poblacion infantil y juvenil.

INTRODUCTION: The use of psychostimulants has been present in common medical practice since the 20th century and has undergone an exponential growth in terms of the number of prescriptions. AIM: To review the current state of knowledge about the side effects of psychostimulants in the child and teen populations. DEVELOPMENT: A review was performed by searching in different databases and included clinical analyses, observational prospective studies and systematic reviews. A minimum increase in blood pressure and heart rate are observed, but some studies highlight an underestimation of the long-term risk. As regards appetite and growth, almost all the current literature points to a slowing of the rate of growth, which is regained on interrupting treatment. One important factor, as is the parallel evolution of bone age, has not been evaluated in most of the studies carried out to date. No significant worsening of sleep was noted in patients treated with psychostimulants with respect to those who are not being treated. With regard to the central nervous system, there does not seem to be any evidence of an increased risk of the appearance or exacerbation of tics following introduction of the treatment. Affect and emotion are areas that have been barely explored. CONCLUSIONS: It is important to have more evidence on the safety of these drugs. It is therefore essential to have access to studies that cover a period of time consistent with the duration of these treatments.

TITLE: Efectos secundarios del metilfenidato en poblacion infantil y juvenil.Introduccion. El uso de farmacos psicoestimulantes esta presente en la practica medica habitual desde principios del siglo XX y ha experimentado un incremento exponencial en cuanto a prescripciones. Objetivo. Revisar el estado de conocimiento actual sobre los efectos secundarios de los psicoestimulantes en poblacion infantil y juvenil. Desarrollo. Se realiza una revision tras consultar diferentes bases de datos, incluyendo en esta revision analisis clinicos, metaanalisis, estudios prospectivos observacionales y revisiones sistematicas. Se observa un incremento minimo en la tension arterial y la frecuencia cardiaca, pero algunos estudios recientes apuntan a una infraestimacion del riesgo a largo plazo. En lo que se refiere al apetito y el crecimiento, casi toda la bibliografia actual apunta a una ralentizacion del ritmo de crecimiento, que se recupera al interrumpir el tratamiento. Un factor importante, como es la evolucion en paralelo de la edad osea, no se ha valorado en la mayoria de los estudios realizados. En el sueño no habria empeoramiento significativo en los pacientes tratados con psicoestimulantes respecto a los no tratados. En relacion con el sistema nervioso central, no parece haber evidencia de un incremento del riesgo de aparicion o empeoramiento de tics tras introducir el tratamiento. El afecto y la emocion son areas poco exploradas. Conclusiones. Es importante tener una mayor evidencia de la seguridad de estos farmacos. Para ello es imprescindible poder disponer de estudios de una extension en el tiempo consecuente con la duracion de estos tratamientos.

Acute Worsening of Tics on Varenicline.

OBJECTIVE: The aim of this study was to report worsening of Tourette syndrome (TS) in 2 patients treated with varenicline. BACKGROUND: Abnormal dopaminergic signaling is likely involved in the pathophysiology of TS. Varenicline is a partial α4ß2 nicotinic acetylcholine agonist that enhances dopamine release. Therefore, the use of varenicline may influence tics in patients with TS. METHOD: We analyzed and described 2 case studies on patients with significant worsening of tics after treatment with varenicline. RESULTS: Patient 1 had motor tics in childhood, which completely resolved by the age of 20 years. At the age of 25 years, he started varenicline and stopped smoking. Within 2 weeks, he developed motor followed by vocal tics that persisted despite stopping varenicline and restarting smoking. The tics were complex, medically refractory, and caused severe disability at work and school (Yale Global Tic Severity Scale score, 86). Patient 2 developed motor and vocal tics in adolescence that persisted into her 20s and caused significant disability in association with psychiatric comorbidities. At the age of 31 years, she started varenicline to quit smoking, which led to a marked increase in tic frequency and severity. Varenicline was discontinued after 3 weeks with improvement to baseline tic severity (Yale Global Tic Severity Scale score, 94). Ultimately, both patients successfully underwent deep brain stimulation to bilateral centromedian/parafascicular complex thalamic nuclei for medically refractory TS. CONCLUSIONS: We report 2 patients with motor and/or vocal tics that had severe worsening of tics after varenicline use. This may be due to varenicline-induced increased striatal dopamine in conjunction with nicotine cessation, influencing dopamine receptor sensitivity in TS. Providers should be cautious in prescribing varenicline to patients with TS.

Pharmacogenetics of methylphenidate response in preschoolers with ADHD.

OBJECTIVE: The authors explored genetic moderators of symptom reduction and side effects in methylphenidate-treated preschool-age children diagnosed with attention-deficit/hyperactivity disorder (ADHD). METHOD: DNA was isolated from 81 subjects in a double-blind, placebo-controlled, crossover methylphenidate titration. Parents and teachers completed ADHD symptom scales and side effect ratings for each of five randomly administered weekly conditions that included immediate-release methylphenidate 1.25, 2.5, 5.0, 7.5 mg and placebo given three times daily. Candidate genes hypothesized to influence stimulant effects or individual risks for ADHD were genotyped. RESULTS: Although the primary analysis did not indicate significant genetic effects, secondary analyses revealed associations between symptom response and variants at the dopamine receptor (DRD4) promoter (p=.05) and synaptosomal-associated protein 25 (SNAP25) allelesT1065G (p=.03) andT1069C (p=.05). SNAP25 variants were also associated with tics (p=.02), buccal-lingual movements (p=.01), and irritability (p=04). DRD4 variants were also associated with picking (p=.03). Increasing dose predicted irritability (p=.05) and social withdrawal (p=.03) with DRD4 variants. There were no significant effects for the dopamine transporter (DAT1). CONCLUSIONS: Emerging evidence suggests the potential for understanding the individual variability of response to and side effects of ADHD medications from the study of genetics, although additional research is required before these findings are proven to have clinical utility.