Caution for psychiatrists: malignant hyperthermia risks with the anesthetic agent succinylcholine (Suxamethonium) during electroconvulsive therapy.

BACKGROUND: Malignant hyperthermia is a potentially lethal condition triggered by specific anesthetic drugs, especially a depolarizing muscle relaxant of succinylcholine (Suxamethonium). Despite the frequent use of succinylcholine with electroconvulsive therapy (ECT), there has been no reported case of potentially lethal malignant hyperthermia following ECT. In addition, the time interval between the administration of succinylcholine and the onset of malignant hyperthermia has not been outlined in the context of ECT. CASE PRESENTATION: We present the case of a 79-year-old woman suffering from severe depression, who experienced severe malignant hyperthermia due to succinylcholine administration during an ECT session. She presented with a high fever of 40.2 °C, tachycardia of 140/min, hypertension with a blood pressure exceeding 200 mmHg, significant muscle rigidity, and impaired consciousness. These symptoms emerged two hours after ECT, which occurred in a psychiatric ward rather than an operating room, and reached their peak in less than 24 h. She was given 60 mg of dantrolene, which quickly reduced the muscular rigidity. Subsequently, she received two additional doses of 20 mg and 60 mg of dantrolene, which brought her fever down to 36.2 °C and completely eased her muscle rigidity within two days after ECT. CONCLUSIONS: This is the first reported case of potentially lethal malignant hyperthermia after ECT. In addition, it highlights the delayed onset of malignant hyperthermia following an ECT procedure, emphasizing the necessity for psychiatrists to recognize its onset even after the treatment. In the light of potentially lethal consequences of malignant hyperthermia, it is critically important for psychiatrists to closely monitor both intraoperative and postoperative patient's vital signs and characteristic physical presentations, promptly identify any symptomatic emergence, and treat it immediately with dantrolene.

Post-stroke urinary incontinence is associated with behavior control deficits and overactive bladder.

BACKGROUND: Although urinary incontinence in stroke survivors can substantially impact the patient's quality of life, the underlying neuropsychological mechanisms and its neural basis have not been adequately investigated. Therefore, we investigated this topic via neuropsychological assessment and neuroimaging in a cross-sectional study. METHODS: We recruited 71 individuals with cerebrovascular disease. The relationship between urinary incontinence and neuropsychological indices was investigated using simple linear regression analysis or Mann-Whitney U test, along with other explanatory variables, e.g., severity of overactive bladder. Variables with a p-value of <0.1 in the simple regression analysis were entered in the final multiple linear regression model to control for potential confounding factors. To carry out an in-depth examination of the neuroanatomical substrate for urinary incontinence, voxel-based lesion-behavior mapping was performed using MRIcron software. RESULTS: Behavioral control deficits and severity of overactive bladder were closely related to severity of urinary incontinence. The voxel-based lesion-behavior mapping suggests a potential role for ventromedial prefrontal cortex lesioning in the severity of urinary incontinence, although this association is not statistically significant. CONCLUSIONS: Post-stroke urinary incontinence is closely related to two factors: neurogenic overactive bladder, a physiological disinhibition of micturition reflex, and cognitive dysfunction, characterized by behavior control deficits.

Shadowing Behavior May Be Associated with an Inability to Recognize the External World: A Case Report of Shadowing in a Patient with Posterior Cortical Atrophy.

Although shadowing behavior- when one individual closely follows another- is routinely documented among patients with dementia, its mechanisms have yet to be elucidated. In particular, there have been no detailed descriptions of patients with shadowing behavior. To propose its potential backgrounds, we describe a patient with posterior cortical atrophy who exhibited prominent shadowing behavior. He also experienced severe difficulties recognizing external stimuli, including visuospatial dysfunction, several types of agnosia, difficulties in verbal comprehension, disorientation, and its associated depression. This shadowing behavior may be adaptive relative to his extreme difficulty with recognizing the world around him.

Pneumonia Risk Increased by Dementia-Related Daily Living Difficulties: Poor Oral Hygiene and Dysphagia as Contributing Factors.

OBJECTIVE: Although pneumonia is the leading cause of death among patients with dementia, the specific underlying causes remain unclear. In particular, the potential connection between pneumonia risk and dementia-related daily living difficulties, such as oral hygiene practice and mobility impairment, and the use of physical restraint as a management practice, has not been extensively studied. METHODS: In our retrospective study, we included 454 admissions corresponding to 336 individual patients with dementia who were admitted to a neuropsychiatric unit due to behavioral and psychological symptoms. The admissions were divided into two groups: those who developed pneumonia while hospitalized (n=62) and those who did not (n=392). We investigated differences between the two groups in terms of dementia etiology, dementia severity, physical conditions, medical complications, medication, dementia-related difficulties in daily living, and physical restraint. To control potential confounding variables, we used mixed effects logistic regression analysis to identify risk factors for pneumonia in this cohort. RESULTS: Our study found that the development of pneumonia in patients with dementia was associated with poor oral hygiene, dysphagia, and loss of consciousness. Physical restraint and mobility impairment showed a weaker, nonsignificant association with the development of pneumonia. CONCLUSIONS: Our findings suggest that pneumonia in this population may be caused by two primary factors: increased pathogenic microorganisms in the oral cavity due to poor hygiene, and an inability to clear aspirated contents due to dysphagia and loss of consciousness. Further investigation is needed to clarify the relationship between physical restraint, mobility impairment, and pneumonia in this population.

Crucial differential diagnosis of rapidly progressive dementia: A case of leptomeningeal metastasis.

Background: Dementia that advances subacutely without accompanying neurological symptoms can often be misdiagnosed as a psychiatric condition. Leptomeningeal metastasis (LM), caused by the spread of malignant cells to the leptomeninges and the subarachnoid space, is a relatively unfamiliar condition to psychiatrists in this context. The diagnosis of LM remains challenging due to the scarcity of diagnostic tools possessing high sensitivity and specificity. Case Presentation: We present the clinical presentation of a male in his seventies with LM secondary to gastric ring cell carcinoma. The patient exhibited an acute confusional state, visual hallucinations, irritability, and cognitive impairments over a 3-week period. Initially, the patient was misdiagnosed with several conditions, including alcohol withdrawal syndrome, psychosis, and delirium associated with dementia, as there were no noteworthy findings on neurological examination or the head magnetic resonance imaging (MRI). Given the rapidly progressive cognitive decline, we maintained vigilance for potential neurological conditions, and a repeat investigation using head MRI and cerebrospinal fluid analysis led to the diagnosis of LM. Conclusion: This critical case report underscores the rarity of psychiatric-onset LM originating from gastric cancer and highlights the importance of comprehensive neurological evaluations.

Caution to psychiatry ward: COVID-19 pneumonia can manifest weeks or months after testing positive with a PCR test in individuals on preexisting immune-suppressing medication.

Background: Some patients are reported to develop depression immediately after COVID-19 infection. Typically, hospitalization is arranged a week to 10 days after symptom onset to avoid outbreak in the psychiatric ward when infectivity is almost eliminated. However, in patients on immunosuppressive drugs, infection is known to persist beyond the 10th day after testing positive with a polymerase chain reaction (PCR) test. Case Presentation: We present a patient with follicular lymphoma who was receiving immune-suppressing medication and contracted a COVID-19 infection; she developed severe depression and eventually required hospitalization 10 days after symptom onset or 5 days after the COVID-19 infection-related symptoms disappeared. Although the patient did not exhibit any symptom of pneumonia upon admission, she developed COVID-19 pneumonia 3 weeks after the initial positive test. She received intravenous infusion of the antiviral drug remdesivir, which led to the improvement of pneumonia, and she was discharged on day 32 from testing COVID-19 positive. However, COVID-19 pneumonia recurred on days 64 and 74. Conclusion: This is the first report of COVID-19 pneumonia developing in a psychiatric ward in a patient on immunosuppressive drugs, weeks to months after testing positive with a PCR test. When patients with compromised immune function, such as those on immunosuppressant medication or those with human immunodeficiency virus disease, are admitted to a psychiatric ward, careful monitoring of the risk of recurrence and sufficient consideration for infection control measures are necessary to avoid outbreaks.

Differentiating autoimmune encephalitis from schizophrenia spectrum disorders among patients with first-episode psychosis.

BACKGROUND: Although differential diagnosis between autoimmune encephalitis and schizophrenia spectrum disorders is crucial for a good outcome, the psychiatric symptoms that distinguish these two conditions have not been identified even though psychiatric symptoms are often the main manifestation of autoimmune encephalitis. Also, there are many situations in clinical psychiatry in which laboratory testing and imaging studies are not available. Because no comparative study of the psychiatric symptoms between these two conditions has been carried out, we explored diagnostically useful psychiatric symptoms in a retrospective case-control study. METHODS: We recruited 187 inpatients with first-episode psychosis who were admitted to our psychiatric unit and categorized them into two groups: the autoimmune encephalitis group (n = 10) and the schizophrenia spectrum disorders group (n = 177). Differences in the symptoms and signs between the two groups were investigated. RESULTS: Schneider's first-rank symptoms (e.g., verbal commenting hallucinations and delusional self-experience) were observed only in the schizophrenia spectrum disorders group, whereas altered perception was found more frequently in the autoimmune encephalitis group. Functional status was worse in the autoimmune encephalitis group, and neurological and neuropsychological signs were revealed almost exclusively in this group. A history of mental illness was more frequently reported in the schizophrenia spectrum disorders group than in the autoimmune encephalitis group. CONCLUSIONS: The psychiatric symptoms, i.e., Schneider's first-rank symptoms and altered perception, together with neurological and neuropsychological signs, functional status, and past history, may help clinicians accurately differentiate these two conditions among patients with first-episode psychosis.

Restrictive type and infectious complications might predict nadir hematological values among individuals with anorexia nervosa during the refeeding period: a retrospective study.

BACKGROUND: Although hematological abnormalities in patients with anorexia nervosa have been documented, the mechanisms involved have not been fully clarified, especially during the refeeding period when hematological values further decrease after admission prior to improving. Here we address potential mechanisms underlying the hematological abnormalities of inpatients with anorexia nervosa during the refeeding period. METHODS: We recruited patients from 101 admissions corresponding to 55 individual patients with anorexia nervosa with severe malnutrition (body mass index, 13.4 ± 3.4) from the neuropsychiatry unit in Ashikaga Red Cross Hospital during the period from October 1999 to March 2018. We analyzed three hematological cell measures, i.e., hemoglobin, white cell count, and platelet count, to determine their levels at admission and their lowest levels during the refeeding period and calculated the percent decrease in those values from admission to the nadir levels. We analyzed each measure using a general mixed model with explanatory variables, including data upon admission and a treatment-related indicator, i.e., energy intake. RESULTS: The initial hemoglobin value of 12.1 ± 2.7 g/dl decreased by 22.3% to 9.4 ± 2.5 g/dl; the initial white cell count was 5387 ± 3474/µl, which decreased by 33.6% to 3576 ± 1440/µl; the initial platelet count of 226 ± 101 × 103/µl decreased by 24.3% to 171 ± 80 × 103/µl. All nadir levels were observed during the refeeding period from the fifth to tenth day of hospitalization. Significant correlations among the three hematological cell measures, particularly at the nadir levels, were found. Of note, 41.7% of our patients who received red blood cell transfusion during hospitalization showed normal hemoglobin levels upon admission. The anorexia nervosa restrictive type was associated with a lower nadir level of white blood cell count. Infectious complications were related to a lower nadir level of hemoglobin and a greater percent decrease in hemoglobin level as well as to the need for red blood cell transfusion. CONCLUSIONS: Nadir hematological cell measures of inpatients with anorexia nervosa might be predicted by the restrictive type and infectious complications. The anorexia nervosa restrictive type was associated with further decrease in hematological values during the refeeding period.

Deficiencies in components of the blood, such as a low red blood cell count, low white blood cell count, and low platelet numbers, are observed frequently in patients with anorexia nervosa, particularly those with severe malnutrition, and these deficiencies become manifest after hospitalization during the initial period when patients are reintroduced to food. Why this deterioration occurs even under medical care is not well understood. Here we analyzed the patient factors associated with these blood cell abnormalities. Patients with the restrictive type of anorexia nervosa, and infectious complications were more likely to have the lowest levels of hematological values during the refeeding period.

Apathy Level, Disinhibition, and Psychiatric Conditions Are Related to the Employment Status of People With Traumatic Brain Injury.

IMPORTANCE: An understanding of the potential prognostic factors as they relate to the employment status of people with traumatic brain injury (TBI) is necessary so that occupational therapy practitioners can provide the most effective treatment. OBJECTIVE: To examine the impact of apathy, disinhibition, and psychiatric conditions on employment status after TBI. DESIGN: An observational study conducted from March 2015 to March 2020. SETTING: Cognitive dysfunction clinics associated with two general hospitals in Japan. PARTICIPANTS: Japanese people of working age (N = 110, ages 18-65 yr) with TBI. Outcomes and Measures: As an outcome indicator, each participant's employment status was rated on a 3-point scale (i.e., 3 = regular employment, 2 = welfare employment [employed as a person with disabilities or undergoing vocational training in the Japanese welfare employment system, for which a worker is paid under either system], 1 = unemployment). Psychiatric, neuropsychological, and physical assessments were measured as explanatory variables. The impact of various factors on employment status was investigated using linear discriminant regression analysis. RESULTS: The level of apathy, disinhibition, and incidence of psychiatric conditions after TBI, as well as age and years postinjury, were related to employment status. Conclusion and Relevance: Although this is a cross-sectional study, interventions for apathy and disinhibition, as well as management of psychiatric conditions, are recommended to help improve employment status among people with TBI. What This Article Adds: The employment status of people with TBI is related more to apathy, disinhibition, and psychiatric conditions than to intelligence, memory function, or executive function.

Symptom changes in patients with pre-existing psychiatric disorders in the initial phase of the COVID-19 pandemic: Vulnerability of female patients and patients with mood disorders.

How patients with pre-existing psychiatric disorders are responding to the COVID-19 pandemic remains unclear, and no comprehensive studies have yet been performed. To elucidate (1) which psychiatric disorders were exacerbated during the initial phase of the COVID-19 pandemic and (2) the contributing factors, we prospectively assessed psychiatric symptoms of 1592 psychiatric outpatients in a single-center study using the Global Assessment of Functioning (GAF) before the state of emergency was declared in Japan and during two months under the state of emergency (study period: April 8 to June 7, 2020). We conducted a chi-squared test for the relationship between psychiatric diagnostic category (ICD-10) and exacerbation. To control for confounders, we conducted a logistic regression analysis using sex, age, diagnostic category, and pre-pandemic GAF score as independent variables. Exacerbation rates of patients with mood disorders (F3) and neurotic disorders (F4) were 4.32% and 5.37%, respectively, and were significantly higher than those for patients with organic disorders (F0) and schizophrenic disorders (F2) (X2 (9, N = 1592) = 27.8, p < .01). Logistic regression analysis revealed that patients with F3 and female patients were significantly more affected than patients with other disorders or male patients, respectively (odds ratio (95% confidence interval) = 2.4 (1.2-4.6), p < .01 for F3; 3.1 (1.5-6.6), p < .01 for females). These findings suggest a need for careful management of patients with mood disorders and female psychiatric patients during a pandemic.

Severe diaphoresis and fever during alcohol withdrawal cause hypovolemic shock: case report.

BACKGROUND: Several fatal medical complications have been associated with alcohol withdrawal, such as seizure, cardiac arrhythmia, and takotsubo cardiomyopathy. However, there have been no reports on hypovolemic shock during alcohol withdrawal, although two physical signs of alcohol withdrawal, i.e., diaphoresis and fever, can lead to hypovolemia and its medical consequences. CASE PRESENTATION: We describe a patient with alcohol use disorder who exhibited hypovolemic shock and its associated acute renal failure during alcohol withdrawal with severe diaphoresis and fever even though he had consumed almost the full amount of food he was offered. Given his excessive diaphoresis and fever that were related to alcohol withdrawal, his water intake was insufficient. Infusion with extracellular fluid resolved all these medical issues. CONCLUSIONS: The increased adrenergic activity associated with alcohol withdrawal might substantially increase a patient's water-intake requirement through diaphoresis and fever and may cause severe hypovolemia and its associated medical complications.

Putative Alcohol-Related Dementia as an Early Manifestation of Right Temporal Variant of Frontotemporal Dementia.

Diagnosis of frontotemporal dementia is challenging in the early stages. Various psychiatric and neurological diseases are misdiagnosed as frontotemporal dementia and vice versa. Here we present a case with right temporal variant of frontotemporal dementia who presented with alcohol dependency and remarkable behavioral symptoms and was first misdiagnosed as having alcohol-related dementia. He then revealed symptoms related to right temporal variant of frontotemporal dementia, such as prosopagnosia, difficulty recognizing his housemates, loss of empathy, ritualistic behaviors, and difficulty finding and comprehending words. Retrospectively, his alcohol dependency itself was considered an early manifestation of right temporal variant of frontotemporal dementia.

Hypokalemia in patients with anorexia nervosa during refeeding is associated with binge-purge behavior, lower body mass index, and hypoalbuminemia.

BACKGROUND: Hypokalemia is frequently found in patients with anorexia nervosa and sometimes leads to life-threatening conditions. Although their serum potassium levels are considered to further decrease during refeeding, no previous studies have addressed actual changes in the serum potassium levels and potential mechanisms underlying hypokalemia during the refeeding period of patients with anorexia nervosa. In this study, we investigated factors associated with hypokalemia during refeeding of patients with anorexia nervosa. METHODS: We recruited 52 independent patients from 89 admissions with anorexia nervosa (body mass index, 13.0 ± 3.3) from the psychiatry unit in Ashikaga Red Cross Hospital during the period from April 2003 to March 2018 and analyzed serum potassium levels at admission. Of the 89 admissions, 66 admissions with > 1-week hospitalization were recruited to determine the lowest potassium levels during the refeeding period. We analyzed these levels with multiple linear regression analysis with explanatory variables, including data upon admission and treatment-related indicators. RESULTS: The initial serum potassium level of 3.6 ± 0.9 mg/dl decreased to 3.1 ± 0.7 mg/dl at nadir hypophosphatemia, which was observed an average of 2.5 days after admission. A lower serum potassium level at admission and a lower nadir potassium level during refeeding were associated with a lower body mass index, hypoalbuminemia, and binge-purge behavior. Similar results were obtained when the analysis included restrictive or binge-purge types as well as the independent patient group. CONCLUSIONS: Lower body mass index, hypoalbuminemia, and binge-purge behavior might be used as indicators to guide clinical approaches for controlling serum potassium levels in patients with anorexia nervosa during refeeding. Hypokalemia, low levels of serum potassium, in patients with anorexia nervosa sometimes leads to life-threatening conditions. Thus, it is of great importance to predict the risk of hypokalemia in patients with anorexia nervosa during the refeeding period. Our study found that hypokalemia in patients with anorexia nervosa during refeeding is associated with a lower body mass index and hypoalbuminemia (low levels of serum albumin), in addition to binge-purge behavior.

Forced Gazing: A Stimulus-bound Behavior.

We studied four patients with acquired brain injury who were compelled to gaze at a moving object or the face of an individual who came into their sight, especially the person's eyes. The patients continued to gaze at the object or person until it disappeared from their sight. This behavior, referred to as forced gazing, is related to visual groping (part of the instinctive grasp reaction), and, together with a similar sign of visual grasping, constitutes a spectrum of visual stimulus-bound behaviors. In addition to forced gazing, the patients exhibited a primitive reflex such as a grasp or sucking reflex. Each of the patients had lesions in the bilateral frontal lobes of the brain. We considered forced gazing to be a stimulus-bound behavior, in which patients become extremely dependent on a specific external stimulus. As gaze-related communication is considered one of the bases of an infant's social development, forced gazing may have its basis in innate human behavior that might manifest itself under specific pathological circumstances such as bilateral frontal-lobe damage.

Visuospatial working memory dysfunction from tapping span test as a diagnostic tool for patients with mild posterior cortical atrophy.

Posterior cortical atrophy is a rare degenerative condition with prominent visuospatial dysfunction which commonly occurs between ages 50 and 65. A diagnosis of mild posterior cortical atrophy sometimes challenging and can be delayed because there are currently no established neuropsychological examination methods that can easily be used in clinical settings. In this study, we examined whether the tapping span test is a potential diagnostic tool for posterior cortical atrophy and what impairment the tapping span test is indicative of in this condition. Eight patients with mild posterior cortical atrophy were recruited. Age- and severity-matched individuals with amnesic Alzheimer's disease (n = 9) were also recruited as a control group. The participants were subjected to the tapping span test and several visuospatial working memory tests. The results of the tapping span and visuospatial working memory tests were worse for the posterior cortical atrophy group when compared with the control group. The results from the tapping span tests were strongly correlated with those from the visuospatial working memory tests. The tapping span test is a simple and potentially useful diagnostic tool for patients with mild posterior cortical atrophy, as it reflects visuospatial working memory function.

"Case series: ischemic stroke associated with dehydration and arteriosclerosis in individuals with severe anorexia nervosa".

BACKGROUND: Numerous reports have indicated that patients with anorexia nervosa (AN) are at a relatively high risk of developing vascular diseases, including cardiovascular events and venous thromboembolism. However, there have been no previous reports of the development of ischemic stroke during refeeding therapy in patients with severe AN. This report is aimed at reporting the characteristics of an ischemic stroke in patients with AN. CASE PRESENTATIONS: Our study included 29 admissions by independent 19 female patients cases (19 patients), who received thorough medical, neurological, and psychiatric examinations. Two patients were diagnosed as having developed ischemic stroke; the first patient showed multiple infarctions in the brain, while the second showed symptomatic focal infarction. Our findings suggest that dehydration and arteriosclerosis, in association with severe malnutrition, could predispose to the development of ischemic stroke in patients with severe AN. CONCLUSIONS: Development of ischemic stroke in patients with AN might be overlooked. Watching out for neurological signs would help in early diagnosis of ischemic stroke in patients with AN during refeeding. Specific etiology could induce ischemic stroke in patients with AN even if they have no common risk factors of ischemia.

Body mass index and blood urea nitrogen to creatinine ratio predicts refeeding hypophosphatemia of anorexia nervosa patients with severe malnutrition.

AIM: To investigate development of refeeding hypophosphatemia during the refeeding period and the extent of the decrease in the serum phosphorus level among anorexia nervosa patients with severe malnutrition. OBJECTIVE: The accurate prediction of the severity of refeeding hypophosphatemia in patients with anorexia nervosa during acute treatment is of great importance. Although some predictors were found in previous reports, these studies used binominal data-the presence or absence of hypophosphatemia-as an outcome indicator but not the extent of serum phosphorus level decrease. It is crucial in clinical settings to predict the extent of the serum phosphorus level decrease as well as development of refeeding hypophosphatemia, in particular, for patients with severe malnutrition, who has a higher risk of death. METHODS: We investigated 63 admissions from 37 patients with anorexia nervosa who had severe malnutrition (admission body mass index 11.5 ± 1.6) and carried out a linear discriminant regression analysis for the development of refeeding hypophosphatemia. The extent of the decrease in the serum phosphorus level were investigated using multiple linear regression analysis. Explanatory variables included data upon admission (age, sex, body mass index, blood urea nitrogen to creatinine ratio, albumin, initial serum phosphorus level, anorexia nervosa type, i.e., restrictive or binge-purge) as well as treatment-related indicators (calorie intake, amount of phosphate administered, and rate of weight gain). RESULTS: Development of refeeding hypophosphatemia and a change in serum phosphorus levels were predicted by body mass index and elevated blood urea nitrogen to creatinine ratio. CONCLUSIONS: Our study found that refeeding hypophosphatemia among patients with severe malnutrition was predicted by a lower body mass index and elevated blood urea nitrogen to creatinine ratio.

Pisa syndrome induced by switching of a choline-esterase inhibitor treatment from donepezil to galantamine: a case report.

BACKGROUND: Pisa syndrome (PS) is characterized by an abnormally sustained posture, with flexion of the body and head to one side and slight rotation of the trunk. Although PS most commonly arises as an adverse effect of antipsychotic drugs, choline-esterase inhibitors (ChEIs) are also sometimes known to induce PS. Despite the fact that the precise mechanism remains unclear, cholinergic-dopaminergic imbalance has been considered as a possible pathophysiologic mechanism underlying the genesis of PS. CASE PRESENTATION: We hereby report the case of a 60-year-old woman with Alzheimer's disease who presented with the signs of PS after her treatment was switched to galantamine, a type of ChEI, even though she had received donepezil, another type of ChEI, for 5 years without any complications. To the best of our knowledge, this is the first report of PS associated with treatment switch from one to another type of ChEI. Galantamine, but not other ChEIs, can enhance striatal dopamine release through allosteric modulation of the nicotinic acetylcholine receptor, and has weaker muscarinic effects than donepezil. Therefore, we propose two novel hypotheses to explain the development of PS, as follows; galantamine, which enhances dopamine release, can induce imbalance of dopamine levels in the striatum of patients with dementia, resulting in PS, and the weaker muscarinic effects of the drug could be one of the factors predisposing to the development of PS. CONCLUSION: The present case suggests that treatment with galantamine is associated with a higher risk of development of PS than that with other ChEIs, such as donepezil, despite the pharmacological profile of galantamine as a dopamine modulator. Also, this report provides novel insight into another plausible mechanism underlying the development of PS, besides cholinergic-dopaminergic imbalance, namely, dopamine imbalance in the striatum with muscarinic-nicotinic imbalance.