Zonisamide or levetiracetam for adults with cyclic vomiting syndrome: a case series

Cyclic vomiting syndrome: From pathophysiology to treatment

Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent and unpredictable episodes of intense vomiting, interspersed with periods of apparent wellbeing. This disorder, which primarily affects children and adolescents but can persist into adulthood, has recently been the subject of extensive study and analysis in the medical literature. The aim of the present review is to examine the most important aspects of the epidemiology, pathophysiology, subtypes, diagnostic criteria, and current management of CVS. Even though the exact etiology remains unknown, genetic factors (polymorphisms), nervous system alterations and autonomic dysregulation, and environmental factors (use and abuse of cannabinoids) are postulated as possible triggers. CVS has significant diagnostic challenges, given that there is no specific test for confirming its presence. Thorough evaluation of symptoms and the ruling out of other possible causes of recurrent vomiting are required. Management of CVS typically involves a multidisciplinary approach. Pharmacologic options are explored, such as antiemetics and preventive medications, as well as behavioral and psychologic support therapies. Treatment personalization is essential, adapting it to the individual needs of each patient. Despite advances in the understanding of CVS, it remains a significant clinical challenge. This disorder impacts the quality of life of those affected and their families, underscoring the ongoing need for research and the development of more effective treatment strategies.

Allergic phenotype identified on allergen testing is associated with proton pump inhibitor nonresponse in eosinophilic esophagitis

BACKGROUND AND AIM

Food/environmental allergens have been associated with eosinophilic esophagitis (EoE); however, the correlation between allergy profiles and disease responsiveness to proton pump inhibitor (PPI) therapy remains unclear. We aimed to assess the association between food/environmental allergies identified on allergen testing and histologic response to PPI in patients with treatment-naive EoE.

METHODS

Adults with newly diagnosed EoE who underwent formal testing for food/environmental allergies at a tertiary center were included. All patients underwent twice-daily PPI for 8 weeks with subsequent repeat endoscopy and biopsy to assess histologic response. Patients with <15 eosinophils/hpf on post-PPI mucosal biopsies were classified as responders (PPI-r-EoE), while those with ≥15 eosinophils/hpf were nonresponders (PPI-nr-EoE).

RESULTS

Sixty-one patients met inclusion criteria (21 PPI-r-EoE vs 40 PPI-nr-EoE). Demographic, clinical, and endoscopic finding variables were similar between groups. Positive food allergen test was more prevalent among PPI-nr-EoE patients (82.5% vs 42.9%, P = 0.003). On multivariable analysis, positive food allergen testing remained an independent predictor for PPI nonresponse (aOR 0.15, CI: 0.04-0.58, P = 0.0006). Positive environmental allergen testing was highly prevalent, with no significant differences between groups (77.5% vs 95.2%, P = 0.14). However, higher number of positive environmental allergens (23.3% [≥5 allergens] vs 73.3% [<5 allergens], P = 0.003) and specific aeroallergens correlated with PPI-nr-EoE.

CONCLUSION

Positive food allergy testing and increased environmental allergens predicted lower likelihood of histologic response to PPI in EoE. Our findings support an allergic phenotype of EoE that may less likely respond to PPI therapy. Formal allergen testing may play a role in therapy selection and tailored management in EoE.

Abdominal migraine and cyclical vomiting syndrome

Abdominal migraine and cyclical vomiting syndrome (CVS) are characteristic syndromes which have overlapping characteristics with migraine but lack the cardinal symptom of headache. Both abdominal migraine and CVS are characterized by recurrent attacks of nausea, vomiting, and/or abdominal pain lasting hours to a few days, with symptom freedom between attacks. Both abdominal migraine and CVS typically occur in children and adolescents, who often go on to develop more typical migraine headaches when older, but may also present for the first time in adults. Due to their shared characteristics and association with migraine headaches, abdominal migraine and CVS are sometimes called "migraine equivalents," and their pathophysiology is assumed to overlap with migraine headache. This chapter describes what is known about the clinical characteristics, epidemiology, pathophysiology, and prognosis of abdominal migraine and CVS, and explores their relationship to migraine. We also review the existing evidence for the nonpharmacological management, acute treatment of attacks, and preventive treatments for both abdominal migraine and CVS.

Current understanding of the etiology of cyclic vomiting syndrome and therapeutic strategies in its management

INTRODUCTION

Cyclic vomiting syndrome is a chronic debilitating disorder of the gut-brain interaction and is characterized by recurrent episodes of nausea and vomiting.Recent studies indicate that it is common and affects 2% of the US population. Unfortunately, there is significant heterogeneity in the management of these patients in the medical community. This review article aims to bridge this gap and will review the epidemiology and etiology with a focus on management of CVS.

AREAS COVERED

This article reviews the epidemiology, and pathophysiology of CVS and impact on patients. It also discusses management based on recent guidelines based on which is intended for the busy clinician. A literature search was done using PubMed and key words "cyclic vomiting", "management", "etiology", and pathophysiology were used to identify articles of importance.

EXPERT OPINION

CVS is a complex, poorly understood disorder of gut-brain interaction (DGBI) and has a significant negative impact on patients, families and the healthcare system. Recent guidelines recommend a multidisciplinary approach to management using prophylactic therapy in moderate-severe CVS and abortive medication for acute flares. However more research is needed to better understand the pathophysiology and develop targeted therapies for CVS.

The clinical value of psycho-gastroenterological interventions for functional esophageal symptoms

BACKGROUND

Disorders of gut-brain interaction (DGBI) are associated with high symptom burden and poor quality of life. We evaluated the clinical value of multimodal therapy with psycho-gastroenterological interventions in patients with refractory functional symptoms.

METHODS

Of 80 DGBI patients managed over a 12-month period, 26 patients undergoing multimodal therapy (median age 60.0 years, 73.1%F) were compared to 54 patients (median age 56.0 years, 68.5%F) managed using conventional approaches. Psycho-gastroenterological multimodal therapy was individualized and included relaxation training (diaphragmatic breathing, passive muscle relaxation) and gut-direct hypnotherapy/guided imagery. All patients completed documentation of symptom frequency and severity using a 100 mm visual analog scale (VAS) and assessment of health-related quality of life (BEST score) before and following therapy. Data were analyzed to determine comparative change in symptom burden between the two cohorts.

KEY RESULTS

Baseline demographics and symptom burden were similar between the two treatment subgroups. While patients improved with both multimodal and conventional therapies, BEST score demonstrated greater improvement with multimodal therapy (p = 0.03). Physician perception of symptom burden at baseline and on follow-up did not correspond to self-reported questionnaire data. On multivariable analysis, multimodal therapy (OR 7.9, 95% CI 1.8-34.6, p = 0.006) and functional esophageal disorders (OR 17.6, 95% CI 2.6-121.1, p = 0.004) predicted >50% improvement in BEST score, while the presence of psychiatric disease was a negative predictor (OR 0.22, CI 0.05-0.94, p = 0.04).

CONCLUSIONS & INFERENCES

Psychological intervention using multimodal therapy provides clinical value to the management of functional esophageal symptoms among patients refractory to conventional therapy.

Levetiracetam Mechanisms of Action: From Molecules to Systems

Epilepsy is a chronic disease that affects millions of people worldwide. Antiepileptic drugs (AEDs) are used to control seizures. Even though parts of their mechanisms of action are known, there are still components that need to be studied. Therefore, the search for novel drugs, new molecular targets, and a better understanding of the mechanisms of action of existing drugs is still crucial. Levetiracetam (LEV) is an AED that has been shown to be effective in seizure control and is well-tolerable, with a novel mechanism of action through an interaction with the synaptic vesicle protein 2A (SV2A). Moreover, LEV has other molecular targets that involve calcium homeostasis, the GABAergic system, and AMPA receptors among others, that might be integrated into a single mechanism of action that could explain the antiepileptogenic, anti-inflammatory, neuroprotective, and antioxidant properties of LEV. This puts it as a possible multitarget drug with clinical applications other than for epilepsy. According to the above, the objective of this work was to carry out a comprehensive and integrative review of LEV in relation to its clinical uses, structural properties, therapeutical targets, and different molecular, genetic, and systemic action mechanisms in order to consider LEV as a candidate for drug repurposing.

Associations of levetiracetam use with the safety and tolerability profile of chemoradiotherapy for patients with newly diagnosed glioblastoma

Background

Levetiracetam (LEV) is one of the most frequently used antiepileptic drugs (AED) for brain tumor patients with seizures. We hypothesized that toxicity of LEV and temozolomide-based chemoradiotherapy may overlap.

Methods

Using a pooled cohort of patients with newly diagnosed glioblastoma included in clinical trials prior to chemoradiotherapy (CENTRIC, CORE, AVAglio) or prior to maintenance therapy (ACT-IV), we tested associations of hematologic toxicity, nausea or emesis, fatigue, and psychiatric adverse events during concomitant and maintenance treatment with the use of LEV alone or with other AED versus other AED alone or in combination versus no AED use at the start of chemoradiotherapy and of maintenance treatment.

Results

Of 1681 and 2020 patients who started concomitant chemoradiotherapy and maintenance temozolomide, respectively, 473 and 714 patients (28.1% and 35.3%) were treated with a LEV-containing regimen, 538 and 475 patients (32.0% and 23.5%) with other AED, and 670 and 831 patients (39.9% and 41.1%) had no AED. LEV was associated with higher risk of psychiatric adverse events during concomitant treatment in univariable and multivariable analyses (RR 1.86 and 1.88, P &lt; .001) while there were no associations with hematologic toxicity, nausea or emesis, or fatigue. LEV was associated with reduced risk of nausea or emesis during maintenance treatment in multivariable analysis (HR = 0.80, P = .017) while there were no associations with hematologic toxicity, fatigue, or psychiatric adverse events.

Conclusions

LEV is not associated with reduced tolerability of chemoradiotherapy in patients with glioblastoma regarding hematologic toxicity and fatigue. Antiemetic properties of LEV may be beneficial during maintenance temozolomide.

Retrospective review of patients treated for cyclic vomiting syndrome with topiramate

BACKGROUND

Practice guidelines recommend topiramate as second-line treatment for the prevention of moderate-severe cyclic vomiting syndrome (CVS) in adults. However, data are limited to small studies in children.

AIM

To characterise the response to topiramate as prophylactic therapy in adults with CVS.

METHODS

We conducted a retrospective review of patients with CVS. Clinical characteristics, number of CVS episodes, emergency department (ED) visits, and hospitalisations the year before and after initiating topiramate were recorded. Response was defined as a global improvement in symptoms or >50% reduction in the number of CVS episodes, ED visits or hospitalisations.

RESULTS

Sixty-five percent (88/136) of patients responded to topiramate in an intent-to-treat analysis. There was a significant decrease in the annual number of CVS episodes (18.1 vs 6.2, P < 0.0001), CVS-related ED visits (4.3 vs 1.6, P = 0.0029), and CVS-related hospitalisations (2.0 vs 1.0, P = 0.035). Logistic regression revealed that higher doses of topiramate, longer use of topiramate (≥12 months) and topiramate as monotherapy were associated with a response to treatment. Anxiety was associated with non-response to topiramate. Fifty-five percent of patients experienced side effects, and 32% discontinued the medication as a result. The most common side effects were cognitive impairment (13%), fatigue (11%) and paresthesia (10%). This represented a refractory group with topiramate being initiated in patients (92%) who had failed treatment with tricyclic antidepressants (TCAs).

CONCLUSIONS

Topiramate may be an effective second-line prophylaxis for patients with moderate-severe CVS, but its use is limited by side effects. Efforts to develop better-tolerated therapies for CVS are warranted.

Cyclic vomiting syndrome: A narrative review and guide to management

OBJECTIVES/BACKGROUND

Cyclic vomiting syndrome (CVS) is a disabling disorder of gut-brain interaction manifested by stereotypical and severe episodes of nausea and vomiting. Prevalence data indicate that CVS affects 1-2% of children and there has been a recent dramatic rise in diagnosed adults.

METHODS

This narrative review summarizes relevant literature pertaining to pediatric and adult CVS and provides a guide to management based on extensive clinical experience.

RESULTS

More timely diagnosis is facilitated by an expert consensus diagnostic approach and limited testing. Some diagnostic tests of exclusion remain essential. These include an upper gastrointestinal (GI) contrast study to exclude intestinal malrotation and basic laboratory screening. An abdominal ultrasound is recommended to exclude renal hydronephrosis in children and biliary disease in adults. Exclusion of metabolic/genetic conditions is warranted in those with specific warning signs, presentation in infants/toddler age, and in those with refractory disease. In the absence of chronic GI symptoms, referral to a GI specialist for upper endoscopy is generally not necessary in children but recommended in adults. A large subset termed migraine-equivalent CVS display strong clinical and genetic features of migraine. A unifying pathophysiologic core concept involves neuronal hyperexcitability and aberrant central modulation of autonomic signals. This is coupled with multiple susceptibility factors including mitochondrial dysfunction/cellular energy deficits, a hyper-responsive hypothalamic-pituitary-adrenal axis and many comorbidities that increase vulnerability to triggering events. CVS episodes are frequently triggered by stressors and intercurrent illnesses. Lifestyle and non-pharmacological interventions thus play a pivotal role in successful management. Pharmacological therapies are categorized into abortive, supportive/rescue, and prophylactic treatments. The majority respond particularly well to migraine-focused treatment strategies.

CONCLUSION

Despite improved characterization and understanding, CVS remains classified as a functional disorder of brain-gut interaction that is often disjointly managed by generalists and subspecialists. Early recognition, evaluation, and management will facilitate care and improve outcomes. Further research into its natural history with common progression to migraine headaches, neuroendocrine mechanisms, and the pathophysiologic relation to migraine diathesis is much needed.

Management of cyclic vomiting syndrome in adults: Evidence review

BACKGROUND

This evidence review was conducted to inform the accompanying clinical practice guideline on the management of cyclic vomiting syndrome (CVS) in adults.

METHODS

We followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework and focused on interventions aimed at prophylactic management and abortive treatment of adults with CVS. Specifically, this evidence review addresses the following clinical questions: (a) Should the following pharmacologic agents be used for prophylaxis of CVS: amitriptyline, topiramate, aprepitant, zonisamide/levetiracetam, or mitochondrial supplements? (b) Should the following pharmacologic agents be used for abortive treatment: triptans or aprepitant?

RESULTS

We found very low-quality evidence to support the use of the following agents for prophylactic and abortive treatment of CVS: amitriptyline, topiramate, aprepitant, zonisamide/levetiracetam, and mitochondrial supplements. We have moderate certainty of evidence for the use of triptans as abortive therapy. We found limited evidence to support the use of ondansetron and the treatment of co-morbid conditions and complementary therapies.

CONCLUSIONS

This evidence review helps inform the accompanying guideline for the management of adults with CVS which is aimed at helping clinicians, patients, and policymakers, and should improve patient outcomes.

Cyclic vomiting syndrome: Pathophysiology, comorbidities, and future research directions

Cyclic vomiting syndrome (CVS) is characterized by severe episodic emesis in adults and children. Cannabinoid hyperemesis syndrome is an increasingly recognized CVS-like illness that has been associated with chronic cannabis use. There are significant gaps in our understanding of the pathophysiology, clinical features, comorbidities, and effective management options of CVS. Recommendations for treating CVS are based on limited clinical data, as no placebo-controlled, randomized trials have yet been conducted. Diseases associated with CVS, including migraine, mitochondrial disorders, autonomic dysfunction, and psychiatric comorbidities, provide clues about pathophysiologic mechanisms and suggest potential therapies. We review our current understanding of CVS and propose future research directions with the aim of developing effective therapy. Establishing a multicenter, standardized registry of CVS patients could drive research on multiple fronts including developing CVS-specific outcome measures to broaden our understanding of clinical profiles, to serve as treatment end points in clinical trials, and to provide a platform for patient recruitment for randomized clinical trials. Such a robust database would also facilitate conduct of research that aims to determine the underlying pathophysiological mechanisms and genetic basis for CVS, as well as identifying potential biomarkers for the disorder. Soliciting government and industry support is crucial to establishing the necessary infrastructure and achieving these goals. Patient advocacy groups such as the Cyclic Vomiting Syndrome Association (CVSA), which partner with clinicians and researchers to disseminate new information, to promote ongoing interactions between patients, their families, clinicians, investigators, to support ongoing CVS research and education, must be an integral part of this endeavor.

Guidelines on management of cyclic vomiting syndrome in adults by the American Neurogastroenterology and Motility Society and the Cyclic Vomiting Syndrome Association

The increasing recognition of cyclic vomiting syndrome (CVS) in adults prompted the development of these evidence-based guidelines on the management of CVS in adults, which was sponsored by the American Neurogastroenterology and Motility Society (ANMS) and the Cyclic Vomiting Syndrome Association (CVSA). GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework was used and a professional librarian performed the literature search. The expert committee included the President of the CVSA who brought a patient perspective into the deliberations. The committee makes recommendations for the prophylaxis of CVS, treatment of acute attacks, diagnosis, and overall management of CVS. The committee strongly  recommends that adults with moderate-to-severe CVS receive a tricyclic antidepressant (TCA), such as amitriptyline, as a first-line prophylactic medication and receive topiramate or aprepitant as alternate prophylactic medications. Zonisamide or levetiracetam and mitochondrial supplements (Coenzyme Q10, L-carnitine, and riboflavin) are conditionally recommended as alternate prophylactic medications, either alone or concurrently with other prophylactic medications. For acute attacks, the committee conditionally recommends using serotonin antagonists, such as ondansetron, and/or triptans, such as sumatriptan or aprepitant to abort symptoms. Emergency department treatment is best achieved with the use of an individualized treatment protocol and shared with the care team (example provided). The committee recommended screening and treatment for comorbid conditions such as anxiety, depression, migraine headache, autonomic dysfunction, sleep disorders, and substance use with referral to appropriate allied health services as indicated. Techniques like meditation, relaxation, and biofeedback may be offered as complementary therapy to improve overall well-being and patient care outcomes.

Cyclic Vomiting Syndrome in Children and Adults: What Is New in 2018?

PURPOSE OF REVIEW

Cyclic vomiting syndrome (CVS) is a disabling functional gastrointestinal disorder characterized by severe vomiting episodes that alternate with symptom-free periods. The purpose of this review is to summarize current knowledge and highlight most recent data on prevalence, diagnosis, management, and impact of CVS in children and adults.

RECENT FINDINGS

Originally thought to be a pediatric disorder, the past decade has witnessed a considerable increase in CVS diagnosed in adults. Despite improved recognition of CVS, without a delineated pathophysiology and specific biomarker, it remains classified as a functional gastrointestinal disorder. Migraines and CVS share a common pathway based on several studies and response to migraine therapy. Recent work has begun to expand the list of comorbidities and identify plausible mechanisms and new therapeutic avenues. This review seeks to highlight best practices and novel therapies for CVS based on expert consensus and review of available literature.

Neuromodulators for Functional Gastrointestinal Disorders (Disorders of Gut-Brain Interaction): A Rome Foundation Working Team Report

BACKGROUND & AIMS

Central neuromodulators (antidepressants, antipsychotics, and other central nervous system-targeted medications) are increasingly used for treatment of functional gastrointestinal disorders (FGIDs), now recognized as disorders of gut-brain interaction. However, the available evidence and guidance for the use of central neuromodulators in these conditions is scanty and incomplete. In this Rome Foundation Working Team report, a multidisciplinary team summarized available research evidence and clinical experience to provide guidance and treatment recommendations.

METHODS

The working team summarized the literature on the pharmacology of central neuromodulators and their effects on gastrointestinal sensorimotor function and conducted an evidence-based review on their use for treating FGID syndromes. Because of the paucity of data for FGIDs, we included data for non-gastrointestinal painful disorders and specific symptoms of pain, nausea, and vomiting. This information was combined into a final document comprising a synthesis of available evidence and recommendations for clinical use guided by the research and clinical experience of the experts on the committee.

RESULTS

The evidence-based review on neuromodulators in FGID, restricted by the limited available controlled trials, was integrated with open-label studies and case series, along with the experience of experts to create recommendations using a consensus (Delphi) approach. Due to the diversity of conditions and complexity of treatment options, specific recommendations were generated for different FGIDs. However, some general recommendations include: (1) low to modest dosages of tricyclic antidepressants provide the most convincing evidence of benefit for treating chronic gastrointestinal pain and painful FGIDs and serotonin noradrenergic reuptake inhibitors can also be recommended, though further studies are needed; (2) augmentation, that is, adding a second treatment (adding quetiapine, aripiprazole, buspirone α2δ ligand agents) is recommended when a single medication is unsuccessful or produces side effects at higher dosages; (3) treatment should be continued for 6-12 months to potentially prevent relapse; and (4) implementation of successful treatment requires effective communication skills to improve patient acceptance and adherence, and to optimize the patient-provider relationship.

CONCLUSIONS

Based on systematic and selectively focused review and the consensus of a multidisciplinary panel, we have provided summary information and guidelines for the use of central neuromodulators in the treatment of chronic gastrointestinal symptoms and FGIDs. Further studies are needed to confirm and refine these recommendations.

Cyclic vomiting syndrome: diagnostic approach and current management strategies

Cyclic vomiting syndrome (CVS) is a disorder characterized by episodes of nausea and vomiting lasting for 1-5 days followed by asymptomatic periods. The etiology of CVS is unknown, but it shares similar characteristics to migraine headaches. CVS is generally classified as having four phases: prodromal, acute/vomiting/hyperemesis, recovery, and remission/interepisodic. Current management strategies include trigger avoidance, abortive and prophylactic medication therapies, and supportive care. The goal of therapy for the remission phase is prophylaxis of further episodes. Antidepressant, antiepileptic, and antimigraine medications show an overall reduction or remission of CVS symptoms in more than 70% of patients. This article provides a summary of diagnostic strategies and reviews current management strategies for CVS.

Cyclic vomiting syndrome: epidemiology, diagnosis, and treatment

Cyclic-vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder characterized by recurrent episodes of nausea and vomiting. Although once thought to be a pediatric disorder, there has been a considerable increase in recognition of CVS in adults. The exact pathogenesis is unknown and several theories have been proposed. Migraine and CVS share a similar pathophysiology as suggested by several studies. Since there are no specific biomarkers available for this disorder, physicians should rely on Rome criteria for the diagnosis. Due to the lack of randomized control trials, the treatment of CVS is primarily empirical.

Cyclic vomiting syndrome: a case series and review of the literature

OBJECTIVE

Cyclic vomiting syndrome (CVS) is under-recognised. Treatment is difficult as the pathophysiology is incompletely understood. We report our experience of treating patients with amitriptyline, and review the literature to summarise symptoms and associated features, epidemiology, potential pathophysiological mechanisms, differential diagnoses and treatment.

DESIGN

Consecutive adult patients with CVS were identified during a 5-year period from January 2010 until December 2015. Medical records were reviewed retrospectively, and age and sex of the patient, symptoms, associated features and response to treatment with amitriptyline were recorded.

SETTING

A luminal gastroenterology clinic at a teaching hospital.

RESULTS

Seventeen patients were identified (mean age 29.8 years, 13 (76.5%) female). Five had a history of cannabis use. Duration of symptoms prior to diagnosis ranged from 5 months to 15 years. Fourteen patients commenced amitriptyline, and in eight (57.1%) symptoms either ceased entirely or improved. Review of the literature suggested the prevalence of CVS was 0.5%. Symptoms are stereotypical, with acute episodes of nausea and vomiting, interspersed by periods when the patient is symptom-free. Proposed pathophysiologies include neuroendocrine dysfunction, mutations in mitochondrial DNA and re-intoxication effects from cannabis stored in fat tissues. Treatment during the acute phase is supportive, with rehydration, sedation and antiemetics. Prophylaxis to prevent future attacks with antihistamines, antimigraine drugs, antiepileptics and tricyclic antidepressants may be beneficial. Complete cessation of cannabis smoking should be advised.

CONCLUSIONS

Diagnosis of CVS is often delayed in adults. Once identified, patients respond well to amitriptyline.

[Cyclic vomiting syndrome in children]

Cyclic vomiting syndrome (CVS) is a misrecognized and probably underdiagnosed disease that can affect up to 1.9% of the pediatric population and can occupy 15% of these children's time. It is characterized by acute attacks of vomiting, occurring with such a strict frequency that some parents can predict the date of their child's next attack. The pathophysiology of CVS is unclear, although the literature recognizes a common origin with migraine headaches, which has the same acute and prophylactic treatment. CVS is now included in the larger group of diseases called "episodic symptoms related to migraine" previously known as "childhood periodic syndromes." To distinguish between real CVS and other differential diagnoses can challenge the clinician. Additional investigations must be considered in accordance with the clinical presentation. Appropriate management of CVS should lead to an improvement in quality of life and school attendance.

Pharmacologic Treatment of Cannabinoid Hyperemesis Syndrome: A Systematic Review

Cannabinoid hyperemesis syndrome (CHS) has become more prevalent with increasing cannabis use. CHS is often resistant to standard antiemetics. The objective of this study is to review the current evidence for pharmacologic treatment of CHS. Medline, PsycINFO, DARE, OpenGrey, Google Scholar, and the Cochrane Library were searched from inception to February 2017. Articles were selected and reviewed independently. Evidence was graded using Oxford Center for Evidence-Based Medicine guidelines. The search resulted in 1262 articles with 63 of them eligible for inclusion (205 human subjects). There were 4 prospective level-2, 3 retrospective level-3 studies, 12 level-4 case series, and 44 level-5 case reports. Among level-2 studies (64 subjects), tricyclic antidepressants (TCAs) and lorazepam were discussed as effective long- and short-term treatments, respectively, in two studies. Ondansetron, promethazine, diphenhydramine, and opioids were also mentioned, but the authors did not comment on their efficacy. Among level-3 studies (43 subjects), one reported effective treatment with antiepileptics zonisamide and levetiracetam, but not TCAs. Another reported favorable response to morphine, ondansetron, and lorazepam but did not specify the actual number of patients receiving specific treatment. Among the level-4 case series (54 subjects), benzodiazepines, haloperidol, and capsaicin were reported as helpful. For level-5 case reports (44 subjects), benzodiazepines, metoclopramide, haloperidol, ondansetron, morphine, and capsaicin were reported as effective. Effective treatments mentioned only once included fentanyl, diazepam, promethazine, methadone, nabilone, levomepromazine, piritramide, and pantoprazole. Hot showers and baths were cited in all level-4 and -5 articles as universally effective. High-quality evidence for pharmacologic treatment of CHS is limited. Benzodiazepines, followed by haloperidol and capsaicin, were most frequently reported as effective for acute treatment, and TCAs for long-term treatment. As the prevalence of CHS increases, future prospective trials are greatly needed to evaluate and further define optimal pharmacologic treatment of patients with CHS.

Novel Treatments for Cyclic Vomiting Syndrome: Beyond Ondansetron and Amitriptyline

OPINION STATEMENT

Cyclic vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder that is characterized by episodic nausea and vomiting. Initially thought to only affect children, CVS in adults was often misdiagnosed with significant delays in therapy. Over the last decade, there has been a considerable increase in recognition of CVS in adults but there continues to be a lack of knowledge about management of this disorder. This paper seeks to provide best practices in the treatment of CVS and also highlight some novel therapies that have the potential in better treating this disorder in the future. Due to the absence of randomized control trials, we provide recommendations based on review of the available literature and expert consensus on the therapy of CVS. This paper will discuss prophylactic and abortive therapy and general measures used to treat an episode of CVS and also discuss pathophysiology as it pertains to novel therapy. Recent recognition of the association of chronic marijuana use with cyclic vomiting has led to the possibility of a new diagnosis called "Cannabinoid Hyperemesis Syndrome," which is indistinguishable from CVS. The treatment for this purported condition is abstinence from marijuana despite scant evidence that marijuana use is causative. Hence, this review will also discuss emerging data on the role for the endocannabinoid system in CVS and therapeutic agents targeting the endocannabinoid system, which offer the potential of transforming the care of these patients.

Functional Nausea in Children

Chronic nausea is a highly prevalent, bothersome, and difficult-to-treat symptom among adolescents. When chronic nausea presents as the predominant symptom and is not associated with any underlying disease, it may be considered a functional gastrointestinal disorder and named "functional nausea." The clinical features of functional nausea and its association with comorbid conditions provide clues to the underlying pathophysiological mechanisms. These may include gastrointestinal motor and sensory disturbances, autonomic imbalance, altered central nervous system pathways, or a combination of these. This review summarizes the current knowledge on mechanisms and treatment strategies for chronic, functional nausea in children.

OnabotulinumtoxinA Injections for the Treatment of Cyclic Vomiting Syndrome

Cyclic vomiting syndrome (CVS) is a disorder characterized by episodes of nausea and vomiting lasting 1 to 5 days, followed by asymptomatic periods. The etiology and pathophysiology of CVS are unknown, but CVS shares similar characteristics to those of migraine headaches. Tricyclic antidepressants have the most evidence and are generally effective for prophylaxis of further episodes in patients with CVS. Second-line pharmacotherapies typically target specific comorbid symptoms or conditions and may include antiepileptic or antimigraine drugs, benzodiazepines, antispasmodics, proton pump inhibitors, antiemetics, and analgesics. OnabotulinumtoxinA (ONABoNT-A) injections have not been studied in the population with CVS but are regarded as a pharmacotherapeutic option for migraine headaches. We describe a 45-year-old woman with a 5-year history of CVS who had failed previous typical prophylactic migraine and CVS pharmacotherapies and was referred to the neurology clinic for management of both of these conditions. On review, the neurologist noted a correlation of the patient's headaches with her CVS symptoms. ONABoNT-A injections were started at 155 units intramuscularly every 12 weeks for her migraine headaches, which also dramatically improved her CVS. The main adverse effect reported by the patient was numbness and weakness in her left shoulder after the injections, which are symptoms consistent with ONABoNT-A injection use; however, these symptoms typically resolved a few days later. Regarded as a pharmacotherapeutic option for migraine headache prophylaxis, ONABoNT-A injections have demonstrated modest efficacy in preventing migraine headaches. Clinicians should be aware that ONABoNT-A injections may also have a role in the prophylaxis of CVS.

Cyclic vomiting syndrome: treatment options

Cyclic vomiting syndrome is a disorder characterized by recurrent episodes of severe nausea and vomiting separated by symptom-free periods. Our aims were to review treatments of adult cyclic vomiting syndrome as well as to identify areas for further clinical research and the unanswered questions in this field. We conducted a PubMed search using such keywords as "cyclic vomiting syndrome," "nausea," "vomiting," "treatment," "trigger factors" and "tricyclic antidepressants" and combined this information with the knowledge and clinical research from the authors. Available data show that in adult cyclic vomiting syndrome, there is an impressive and sustained response to high-dose tricyclic antidepressants. In up to 13% who are regarded as poor responders to tricyclic antidepressants, a predictable profile can be identified related to coexisting psychological disorders, marijuana use, poorly controlled migraine headache or chronic narcotic use. Cyclic vomiting syndrome in adults is being an increasingly recognized entity. Tricyclic antidepressants are the main treatment for controlling symptoms. Eliminating and addressing trigger factors are an essential part of management.

The two sides of opioids in cyclical vomiting syndrome

Background:

Cyclical vomiting syndrome is increasingly recognized in adults, with recent reports suggesting ‘coalescing attacks’ in one third of the patients. We hypothesized that the common need for opioid treatment may contribute to coalescing attacks through development of opioid dependence and withdrawal, triggering cyclical vomiting syndrome.

Aim:

This study was to review iatrogenic opioid dependence as the potential cause for triggering cyclical vomiting syndrome.

Materials and Methods:

A retrospective review was performed to identify patients treated for cyclical vomiting syndrome by a single physician between Jan and December of 2010. Demographic data, clinical presentation, treatment, cumulative opioid prescription during hospitalizations and emergency room visits and days of inpatient stay were abstracted from the chart.

Results:

Forty-one patients (mean age 37.5.6 ± 2.6 years; 66% female) were seen within this timeframe. In eleven patients (27%) with ongoing opioid use, the initial cyclical illness had progressed and eventually coalesced. A cohort of 23 patients was followed for at least 6 months (12.3 ± 1.7 months). The best single predictor of repeat hospitalizations was the cumulative opioid dosage.

Conclusion:

Continued use of opioid therapy is a poor prognostic marker of cyclical vomiting syndrome and may contribute to disease coalescence, with dependence and withdrawal triggering recurrent episodes.

Symptomatic diffuse esophageal spasm as a major ictal manifestation of post-traumatic epilepsy: a case report

Post-traumatic epilepsy (PTE) can create diagnostic confusion when typical epileptic seizures are not manifest. Abdominal symptoms as a manifestation of PTE are rare in this setting. We present a 43-year-old female with paroxysmal chest and abdominal pain, nausea, salivation, and intermittent dysphagia. Esophageal testing demonstrated diffuse esophageal spasm, but smooth muscle relaxants provided no relief. Finally, after history revealed that a motor vehicle accident temporally preceded symptom onset, video electroencephalography confirmed PTE. Therapy with anti-epileptic drug completely resolved symptoms, and the esophageal motor pattern normalized. We speculate that abnormal epileptiform discharges from the seizure focus altered cerebral input to intrinsic esophageal innervation, resulting in inhibitory dysfunction and a picture resembling diffuse esophageal spasm. This is the first report of symptomatic esophageal spasm as a major ictal manifestation of PTE.

Sensory neuromodulators in functional nausea and vomiting: predictors of response

BACKGROUND

Tricyclic antidepressants (TCAs) are known to benefit subjects with functional nausea and vomiting (FNV), but it is not known if alternate neuromodulators are also beneficial. We retrospectively evaluated outcomes and clinical predictors of response in FNV subjects treated with any neuromodulator, including TCAs.

METHODS

We identified 94 subjects (43.8±1.4 year, 79 F) with FNV (Rome III criteria) over a 12 year period, treated with neuromodulators and followed up for 8.5±1.1 months. Clinical presentation, demographics and gastric emptying study (GES) findings (when available) were extracted. Likert scales determined symptom severity at baseline and symptom response or remission at follow-up. Outcomes and predictors of response were evaluated using univariate and multivariate analyses.

RESULTS

At least moderate symptom improvement was reported by 72.3%, and 22.3% had symptom remission. Proportions achieving moderate improvement and remission, and mean outcome Likert scores were similar regardless of neuromodulator agent used or GES status. On univariate and multivariate logistic regression analysis, baseline symptom severity affected symptom response, and pain negatively impacted symptom remission to treatment (p≤0.04 for each); GES status failed to predict treatment response or remission.

CONCLUSIONS

Symptom improvement with neuromodulators may be seen in over two-thirds of subjects with FNV regardless of the specific agent administered. Response may be suboptimal in pain predominant presentations.

The management of cyclic vomiting syndrome: a systematic review

Cyclic vomiting syndrome (CVS) is a rare abnormality of the neuroendocrine system that affects 2% of children. It is a frequently missed diagnosis in the emergency department and may require a number of emergency department visits before the diagnosis is made. The objectives of this review are to identify the clinical features that suggest a diagnosis of CVS and to review the literature on its management. The MEDLINE and EMBASE databases were searched from January 1948 to October 2011 using the keywords 'Cyclic' or 'Vomiting'. Papers were excluded if they did not follow the consensus guidelines or if they were case reports. This review analysed 1093 cases of cyclic vomiting in 25 papers that fulfilled the inclusion criteria. All except one paper were retrospective studies. The size of these cohort studies ranged from three to 181 patients, with a mean patient size of 29. This review found that over 40% of patients have headaches/migraines, with associated anxiety and depression in ≈ 30% of cases. There is a family history of headaches/migraines in 38.9%, and this association was much stronger in the adult CVS cohort compared with the paediatric cohort. Compared with paediatric CVS, adults have a longer duration of attacks and they occur more frequently (5.9 vs. 3.4 days, 14.4 vs. 9.6 episodes/year). Limited data are available on the treatment of the acute phase of CVS, but in adults, sumatriptan has been shown to be effective. For prophylactic treatment, tricyclics are effective in both adult and paediatric CVS, with a clinical response in 75.5 and 67.6% of patients, respectively, in nonplacebo-controlled cohort studies. Furthermore, propranolol has been shown to be useful in children. CVS is an intractable illness with a major impact on the patient's quality of life. There is a long duration between the onset of symptoms and the diagnosis of the condition. There is a high association with headaches/migraines and anxiety/depression. The symptoms are more severe in adult-onset CVS. Tricyclic antidepressants have good efficacy in reducing the frequency/duration or the intensity of attacks. There is limited evidence on the acute management of CVS.

Cyclic vomiting syndrome in 28 patients: demographics, features and outcomes

INTRODUCTION

Cyclic vomiting syndrome (CVS) is a condition characterized by recurrent, stereotyped, attacks of intense nausea and intractable vomiting with no identifiable cause. The diagnosis is made according to the Rome III criteria; however, the condition remains a heterogenous group of symptoms and few studies have analysed patient-reported features in detail. Tricyclic antidepressants may benefit some patients, but there are no data on the long-term outcomes of this condition.

METHODS

This is a retrospective cohort study of all patients treated at two London teaching hospitals between 1994 and 2011. Information was obtained by means of inpatient case notes, clinic letters and telephone interviews using a standardized questionnaire.

RESULTS

Twenty-eight patients were identified, 17 with adult-onset CVS and 11 with childhood-onset CVS. In the adult-onset CVS cohort, the average age of onset was 30 years; the prevalence of headache was 57.1% and anxiety/depression 21.7%. Vomiting attacks occurred on average 10 times a year with a mean duration of 55.3 h. In the childhood-onset CVS cohort, the average age of onset was 5 years and the prevalence of headaches was 44.4%. Vomiting attacks occurred on average 25.5 times a year with a mean duration of 54.5 h. During acute attacks, patients rated morphine-based medications as the most efficacious. Overall, 65.4% of our patients were not treated with long-term prophylactic medications and, of these, 42.1% felt that their symptoms had improved and 26.3% reported complete resolution.

CONCLUSION

CVS is a debilitating illness with frequent attacks of prolonged duration. There is a high association with anxiety/depression as well as headaches. Antimigraine medication, β-blockers and antiepileptic treatment may be successful at attenuating attacks; however, in this long-term study, the prognosis of patients not treated with these medications was also good. Overall, 61.9% of patients showed a gradual improvement in symptoms and 23.8% had complete resolution after a mean of 7 years.

Cyclic vomiting syndrome and functional vomiting in adults: association with cannabinoid use in males

BACKGROUND

Cyclic vomiting syndrome (CVS) is characterized by stereotypical episodes of vomiting separated by symptom-free intervals. However, the difficulty encountered in the management of patients with CVS may be a reflection of a deficiency in our understanding of the disorder. We aimed to evaluate whether clinical or gastric emptying (GE) data discriminate patients labeled as having CVS from functional vomiting (FV) or irritable bowel syndrome (IBS).

METHODS

The medical records of patients diagnosed with any vomiting (including CVS, FV) over a 13-year period (1993-2006) at our institution were carefully reviewed. Disease controls were age and gender matched subjects with IBS. Gastric emptying was performed by scintigraphy (99mTc-egg meal). The associations of clinical factors and GE data with patient status (CVS vs FV or IBS) were analyzed.

KEY RESULTS

A total of 82 patients with CVS and 62 FV patients were identified. Younger age [per 10 years, OR = 0.7 (0.5, 0.9)], male gender [OR = 0.4 (0.2, 0.9)], and cannabinoid use [OR = 2.9 (1.2, 7.2)] were significantly associated with CVS compared with FV. However, there were no significant associations between patient status (CVS vs FV) and age, BMI, smoking, alcohol use, gastrointestinal symptoms, or GE. The proportion of cannabinoid users was significantly higher in patients with CVS compared with patients with IBS, whereas proportions for headaches and psychiatric disease were higher in subjects with IBS.

CONCLUSIONS & INFERENCES

Cyclic vomiting syndrome (vs FV) was not associated with clinical factors, but was associated with younger age, male gender and cannabinoid use. A larger proportion of CVS (vs IBS) patients had used cannabinoids.

Review article: cyclic vomiting syndrome in adults--rediscovering and redefining an old entity

BACKGROUND

Cyclic vomiting syndrome is a disorder characterised by recurrent episodes of severe nausea and vomiting separated by symptom-free periods.

AIMS

To review the history, epidemiology, clinical aspects, pathophysiology, diagnosis and treatments of adult cyclic vomiting syndrome as well as to identify areas for further clinical research and the unanswered questions in this field.

METHODS

We conducted a PubMed search using such keywords as cyclic vomiting syndrome; nausea; vomiting; pathophysiology; diagnosis; treatment; trigger factors; gastric emptying test; autonomic nerve function test; gastrointestinal hormones; outcome and natural history and combined this information with the knowledge and extensive clinical research and publications from the authors.

RESULTS

Available data show that in adult cyclic vomiting syndrome, severe epigastric and sometimes diffuse abdominal pain accompanies most cycles of nausea and vomiting interspersed with periods of symptomatic remission. Psychological disorders, specifically anxiety and depression are common, and gastric emptying is actually rapid in approximately 60% of patients and normal in the remainder. There is an impressive and sustained response to high-dose tricyclic antidepressants. In up to 15% who are regarded as poor responders to tricyclic antidepressants, a predictable profile can be identified related to co-existing psychological disorders, marijuana use, poorly controlled migraine headache or chronic narcotic use.

CONCLUSIONS

Cyclic vomiting syndrome in adults is an entity that is being increasingly recognised, but the need to educate Internists, Gastroenterologists and Emergency Department staff remains an ongoing challenge.

Cyclic vomiting syndrome in a male patient with history of renal cell carcinoma status post nephrectomy

Cyclic vomiting syndrome (CVS) is a condition whose symptoms are recurring attacks of intense nausea, vomiting and sometimes abdominal pain and/or headaches or migraines. Cyclic vomiting usually develops during the childhood ages of 3 - 7; whereas it often remits during adolescence, it can persist into adult life. We report a case of a 57 years old Caucasian male with a history of renal cell carcinoma status post left nephrectomy presenting with a 7 years history of intermittent nausea and vomiting with prodromal malaise, watery diarrhea, flushing and diaphoresis. Cyclic vomiting syndrome is a debilitating functional brain-gut disorder that was initially characterized in children, but now is increasingly recognized to occur also in adults.

Efficacy of tricyclic antidepressant therapy in adults with cyclic vomiting syndrome: a two-year follow-up study

AIM

To investigate the effects of prolonged tricyclic antidepressants (TCAs) therapy on the frequency and duration of episodes of cyclic vomiting syndrome (CVS) in adults, and the global assessment of clinical improvement and the number of emergency department (ED) visits and/or hospitalizations.

METHOD

An open labeled study was conducted in adult CVS patients treated with a TCA and followed for up to 2 years. Demographic data, TCA dosage, duration and frequency of CVS episodes, ED visits, and hospitalizations at baseline and during TCA therapy were recorded, and patients were monitored for any adverse events.

RESULTS

Forty-six patients initially met the inclusion criteria and 41 patients (22 male) with mean age of 35 years (range: 18 to 63 y) on TCA were able to be followed for 1 year and 23 were evaluated for 2 years. Mean age of onset of CVS symptoms was 26 years (range: 10 to 52 y) and mean age for making the diagnosis of CVS was 32 years (range: 15 to 63 y). The frequency and duration of an episode and ED visits related to CVS were all significantly reduced after both the first and second year of TCA therapy (P<0.05). Eighty-eight percent reported an improved clinical status by subjective global assessment. Mild side effects were reported in 34% not necessitating stoppage of the TCA.

CONCLUSIONS

Long-term TCA therapy significantly reduces the frequency and duration of CVS episodes, ED visits, and hospitalizations (P<0.05), and improves overall clinical well-being providing evidence that they are effective therapy for adult CVS.

North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition consensus statement on the diagnosis and management of cyclic vomiting syndrome

Cyclic vomiting syndrome (CVS) is a disorder noted for its unique intensity of vomiting, repeated emergency department visits and hospitalizations, and reduced quality of life. It is often misdiagnosed due to the unappreciated pattern of recurrence and lack of confirmatory testing. Because no accepted approach to management has been established, the task force was charged to develop a report on diagnosis and treatment of CVS based upon a review of the medical literature and expert opinion. The key issues addressed were the diagnostic criteria, the appropriate evaluation, the prophylactic therapy, and the therapy of acute attacks. The recommended diagnostic approach is to avoid "shotgun" testing and instead to use a strategy of targeted testing that varies with the presence of 4 red flags: abdominal signs (eg, bilious vomiting, tenderness), triggering events (eg, fasting, high protein meal), abnormal neurological examination (eg, altered mental status, papilledema), and progressive worsening or a changing pattern of vomiting episodes. Therapeutic recommendations include lifestyle changes, prophylactic therapy (eg, cyproheptadine in children 5 years or younger and amitriptyline for those older than 5), and acute therapy (eg, 5-hydroxytryptamine receptor agonists, termed triptans herein, as abortive therapy, and 10% dextrose and ondansetron for those requiring intravenous hydration). This document represents the official recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition for the diagnosis and treatment of CVS in children and adolescents.

Cyclic vomiting syndrome in adults

Cyclic vomiting syndrome (CVS) was initially described in children but can occur in all age groups. Cyclic vomiting syndrome is increasingly recognized in adults. However, the lack of awareness of CVS in adults has led to small numbers of diagnosed patients and a paucity of published data on the causes, diagnosis and management of CVS in adults. This article is a state-of-knowledge overview on CVS in adults and is intended to provide a framework for management and further investigations into CVS in adults.