Mirtazapine-associated movement disorders: A literature review

Akathisia and oculogyric crisis in hyperemesis gravidarum

Hyperemesis gravidarum complicates 0.5-2% of pregnancies. HG is associated with insomnia, significantly increased risks of anxiety and depression, and may be associated with feelings of guilt, social isolation and thoughts of suicidal ideation or termination of pregnancy. Anti-emetic therapy may be complicated by akathisia and dystonic reactions, which may affect the ongoing management of nausea and vomiting. A case of akathisia and oculogyric crisis following the addition of parenteral prochlorperazine to ondansetron and metoclopramide is presented. The treatment options for extrapyramidal side effects with anti-emetics in pregnancy and for ongoing treatment of nausea and vomiting are discussed.

Quantification of mirtazapine in tablets via DNA binding mechanism; development of a new HPLC method

Atypical antidepressant mirtazapine (MIR) is mostly prescribed for the management of major depressive disorder. The identification of MIR in pharmaceutical dosage forms was made possible by developing a novel, quick, sensitive high-performance liquid chromatography (HPLC) approach that was verified in accordance with ICH recommendations. In the first part of this study, HPLC investigations were optimized with regard to variables including pH, working column, mobile phase, temperature, and flow rate. The limit of detection (LOD) was 0.013 ppm, the limit of quantification (LOQ) was 0.044 ppm, and the linear range was computed as 0.5-15 ppm (R2 = 0.9998). The recovery investigation assessed the method's accuracy, which was shown to range between 98.82 and 100.97 %. In the second part, by using UV-vis spectroscopy, HPLC, thermal denaturation, and viscosity measurements, the mechanism of binding interaction of MIR with double-stranded fish sperm deoxyribonucleic acid (dsDNA) has been thoroughly studied. The DNA binding constants (Kb) were determined using UV-Vis absorption and HPLC methods. To investigate the interactions of MIR with dsDNA, molecular docking calculations and additionally, molecular dynamics simulations were performed. Results showed that MIR is located in the minor groove of dsDNA, and in addition to hydrogen bonding, electrostatic interaction is also formed between the aromatic ring of MIR and phosphate oxygen of dsDNA. Finally, a binding characterization study using MIR tablets was also conducted in order to assess the interaction mechanism of the DNA with the drug using the validated analytical procedure developed for the MIR molecule.

Gabapentin-Associated Movement Disorders: A Literature Review

BACKGROUND

Gabapentin (GBP)-induced movement disorders (MDs) are under-recognized adverse drug reactions. They are commonly not discussed with patients, and their sudden occurrence can lead to misdiagnosis. This literature review aims to evaluate the clinical-epidemiological profile, pathological mechanisms, and management of GBP-associated MD.

METHODS

Two reviewers identified and assessed relevant reports in six databases without language restriction between 1990 and 2023.

RESULTS

A total of 99 reports of 204 individuals who developed a MD associated with GBP were identified. The MDs encountered were 135 myoclonus, 22 dyskinesias, 7 dystonia, 3 akathisia, 3 stutterings, 1 myokymia, and 1 parkinsonism. The mean and median ages were 54.54 (SD: 17.79) and 57 years (age range: 10-89), respectively. Subjects were predominantly male (53.57%). The mean and median doses of GBP when the MD occurred were 1324.66 (SD: 1117.66) and 1033 mg/daily (GBP dose range: 100-9600), respectively. The mean time from GBP-onset to GBP-associated MD was 4.58 weeks (SD: 8.08). The mean recovery time after MD treatment was 4.17 days (SD: 4.87). The MD management involved GBP discontinuation. A total of 82.5% of the individuals had a full recovery in the follow-up period.

CONCLUSIONS

Myoclonus (GRADE A) and dyskinesia (GRADE C) were the most common movement disorders associated with GBP.

A 9-year-old female with iron deficiency has severe periodic limb movements while taking mirtazapine for insomnia

Mirtazapine is a Food and Drug Administration-approved atypical antidepressant used off-label for insomnia. Mirtazapine has been associated with movement disorders in adults. A 9-year-old female was seen in the sleep clinic for symptoms of insomnia, nocturnal awakenings, restless sleep, and growing pains. Mirtazapine was started prior to presentation for severe insomnia. A sleep study showed frequent repetitive leg movements prior to sleep onset as well as significant periodic limb movement disorder with a periodic limb movement index of 25.1/hour. The child was found to have a ferritin level of 23 ng/mL and an iron saturation of 10%. There were concerns that the presence of iron deficiency along with the use of mirtazapine may have contributed to the elevated periodic limb movement index. After starting iron therapy to treat the child's iron deficiency, mirtazapine was weaned off, with further clinical improvements in sleep quality reported. A follow-up sleep study showed a resolution of her periodic limb movement disorder with a periodic limb movement index of 1.4/hour. This is the first pediatric case to describe a sleep-related movement disorder associated with the use of mirtazapine and polysomnographic data to support resolution after discontinuation of mirtazapine along with iron therapy.

CITATION

Hawkins M. A 9-year-old female with iron deficiency has severe periodic limb movements while taking mirtazapine for insomnia. J Clin Sleep Med. 2023;19(7):1369-1373.

Frequency, risk factors, and impacts on quality of life of the restless legs syndrome and side effects among antidepressant users in a tertiary hospital: an observational cross-sectional study

Restless leg syndrome (RLS) is a common but underestimated sensorimotor disorder that significantly affects the quality of life (QoL) which can be induced by antidepressants. This study aims to investigate the frequency and potential risk factors of RLS and side effects in selective serotonin reuptake inhibitors/serotonin and noradrenaline reuptake inhibitors (SSRI/SNRI) users. This cross-sectional study included 198 outpatients who received SSRI/SNRI for 4-8 weeks. Clinical evaluation was performed using the International Restless Leg Syndrome Study Group rating scale for RLS, Udvalg for Kliniske Undersøgelser side effects rating scale, and a short form 36 (SF-36) questionnaire for QoL. The frequency of RLS was 25%. RLS significantly increased with smoking and habituality. Also, habituality increased neurologic side effects reporting. The use of antipsychotics and calcium channel blockers decreased reporting of autonomic side effects. QoL decreased with RLS, psychiatric, neurologic, autonomic, and other side effects in different domains of SF-36. These findings suggested that SSRI/SNRI use could be associated with a higher risk of RLS, especially in smokers. QoL could be influenced negatively by RLS and all side effects. However, further prospective studies are needed to confirm these associations in large samples.

Phenytoin-associated movement disorder: A literature review

Phenytoin (PHT) was first synthesized as a barbiturate derivative and was approved in 1953 by the Food and Drug Administration. This work aimed to review the pathophysiology, epidemiology, clinical presentation, and treatment of PHT-associated movement disorders (MDs). Studies were searched in relevant databases (ScienceDirect, Google Scholar, Excerpta Medica, Latin American and Caribbean Health Sciences Literature, Medline, and Scientific Electronic Library Online) and were selected by two reviewers irrespective of language between 1963 and 2021. Papers of PHT-induced ataxia alone or tremor were excluded. In total, 127 reports with 219 individuals who developed MDs associated with PHT were encountered. MDs found: 126 dyskinesias, 49 myoclonus, 19 dystonia, 14 parkinsonism, 6 tics, 3 stuttering, and 2 restless legs syndrome. The mean age was 35 years (standard deviation [SD]: 23.5) and the predominant sex was male (53.4%). The mean PHT dose when the MD took place was 370.4 mg (SD: 117.5). A serum PHT concentration was reported in 103 cases, ranging from 4 to 110 μg/mL (median: 27.7 μg/mL). No significant relationship was found between PHT dose and age or PHT level. The mean onset time of PHT-associated MD was 23.4 months (SD: 4.4). The mean recovery time after MD management was 3.7 weeks (SD: 1.1). Regarding management, the most common form was PHT withdrawal in 90.4%. 86.3% of the individuals recovered fully. PHT-induced MD was extensively reported in the literature. Only general terms were used in the majority of the reports. The mechanisms underlying the adverse events caused by PHT probably depend on the presence of predisposing factors.

Treatment of Depression with Vortioxetine in a Patient with Comorbid Major Depressive Disorder and Restless Legs Syndrome: A Case Report

Many case reports have shown that the use of antidepressants can lead to restless legs syndrome (RLS). Vortioxetine is a new generation antidepressant with a multimodal mechanism of action on serotonin receptors. In this case report, partial improvement in RLS symptoms after treatment with vortioxetine in a patient with a co-diagnosis of major depressive disorder and restless legs syndrome will be discussed. A 59-year-old female patient was admitted to the psychiatry outpatient clinic due to depressive complaints for three months. In the control examination, it was learned that the patient had complaints of RLS that had been going on for about 20 years. RLS symptoms were increased with selective serotonin reuptake inhibitors (SSRI) used by the patient. In the follow-up examination in the first month after vortioxetine treatment, clinically significant improvement was observed in the patient's depressive complaints, while a partial reduction in RLS symptoms was observed.

Lithium-associated movement disorder: A literature review

In 1949, Cade described “sedative effects” after injecting guinea pigs intraperitoneally with lithium (LTM) carbonate. Based on his experiments, he began treating psychiatric patients with LTM. This literature review aims to evaluate the clinical epidemiological profile, pathological mechanisms, and management of LTM-associated movement disorder (MD). Relevant reports in six databases (Excerpta Medica, Google Scholar, Latin American and Caribbean Health Sciences Literature, Medline, Scientific Electronic Library Online, and ScienceDirect) were identified and assessed by two reviewers without language restriction from 1949 to 2021. A total of 250 reports containing 1100 individuals who developed MD associated with LTM were identified. The MDs encountered 148 parkinsonism (PKN), 114 dyskinesia (DKN), 97 myoclonus, 22 dystonia (DTN), 20 Creutzfeldt–Jakob-like syndrome, 11 akathisia, 10 restless legs syndrome (RLS) symptoms, 6 tics, 5 cerebellar syndromes, and 3 stuttering. In the subgroup of cases not clearly defined, there were 320 individuals with extrapyramidal symptoms, 135 with DTN, 37 with DKN, 24 with PKN, and 7 with RLS. Other 141 individuals were only described as presenting an abnormal involuntary movement without further explanation. The mean age was 53.06 years (standard deviation [SD]: 15.64) and the predominant sex was female, i.e., 56.20% (154/274). The mean LTM dose was 963.03 mg/day (SD: 392.03). The mean serum LTM level was 1.53 mEq/L (SD: 1.08). The median onset time was 3 months (1 day to 40 years). The mean recovery time was 0.94 months (SD: 0.87). 45.94% had a full recovery. LTM-induced MD was extensively reported in the literature. Only general terms were used in the majority of the reports. LTM polytherapy probably affected the identification of the MD cause.

[Sleep and sleep disorders in old age]

The increasing interruptions of night sleep with normal ageing must be distinguished from sleep disorders. Somatic and psychiatric morbidity as well as medication have a huge impact on sleep. Furthermore, the relationship between sleep and morbidity is mutual. Disturbed sleep modifies the clinical appearance of diseases and morbidity affects the ability to sleep. Especially in geriatric medicine, geriatric syndromes such as falls, depression or dementia are modified by sleep disorders. Therefore, treatment for sleep disorders offers the chance to improve geriatric syndromes.When treating, it is important to identify the individual sleep disorders. Coincidences of different sleep disorders are common in the elderly. The history of a patient in connection with a sleeping diary is the basic diagnostic procedure. Sleep medicine provides further technical methods for further examination. Older people should also be examined in a sleep laboratory if the results have consequences that will be accepted by the patient. However, this should be clarified in advance.

Treatable Hyperkinetic Movement Disorders Not to Be Missed

Hyperkinetic movement disorders are characterized by the presence of abnormal involuntary movements, comprising most notably dystonia, chorea, myoclonus, and tremor. Possible causes are numerous, including autoimmune disorders, infections of the central nervous system, metabolic disturbances, genetic diseases, drug-related causes and functional disorders, making the diagnostic process difficult for clinicians. Some diagnoses may be delayed without serious consequences, but diagnosis delays may prove detrimental in treatable disorders, ranging from functional disabilities, as in dopa-responsive dystonia, to death, as in Whipple's disease. In this review, we focus on treatable disorders that may present with prominent hyperkinetic movement disorders.

Sleep Disorders and Mood, Anxiety, and Post-Traumatic Stress Disorders: Overview of Clinical Treatments in the Context of Sleep Disturbances

Sleep disruptions are frequently reported by persons with mood, anxiety, and post-traumatic stress disorders, and co-occur with psychiatric disorders. There is evidence that sleep disorders can predict the likelihood of developing a future psychiatric disorder and exacerbate existing symptoms. Understanding the inter-relationships between sleep and psychiatric disorders is important. The primary goals of this article are to describe the interactions between psychiatric and sleep disorders in the context of sleep disturbances, underscore the bidirectional effects of mental health treatments on sleep disorder outcomes, and provide general recommendations to optimize treatment in the context of sleep disturbances.

Relative frequency of drug-induced sleep disorders for 32 antidepressants in a large set of Internet user reviews

STUDY OBJECTIVES

It is known that antidepressant drugs can induce sleep disorders in patients, but little data exist about high or low-risk molecules. The aim was to study the frequency of antidepressant drugs-induced sleep disorders (DISD) by molecule.

METHODS

77,391 patient comments for 32 antidepressant drugs were collected from drug review websites and screened for DISD. Association between drugs and nightmare disorder, restless legs syndrome, sleep paralysis, sleep terrors, sleep-related hallucinations or sleep walking was expressed as relative proportion [proportional reporting ratio (PRR)]. A detailed analysis of the dreams content was also carried out.

RESULTS

Amitriptyline, doxepin, fluvoxamine, mirtazapine, nortriptyline, trazodone, venlafaxine and vilazodone were associated with a greater frequency of DISD compared to other antidepressants. Vilazodone heavily increased the probability of developing 5 of the 6 studied DISD (PRR 3.3 to 19.3) and mirtazapine increased the probability for developing 4 DISD (PRR 2.4 to 6.4). Bupropion and citalopram were associated with lower probabilities for 5 DISD (PRR 0.2 to 0.7). Sentiment analysis showed that patients described disturbing dreams for vilazodone or mirtazapine and strange but less negative dreams for bupropion, citalopram or duloxetine.

CONCLUSIONS

Relative frequencies of sleep disorders were obtained for a vast panel of antidepressant drugs through an original analysis of user's drug reviews on drug rating websites. Our results could guide clinicians in appropriate choice of antidepressant drug for high DISD-risk patients in need of such treatment. These results may however be cautiously taken, considering the uncertain reliability and generalisability of web-based data.

[Sleep and Sleep Disturbance in Subjetcs with Dementia]

Treating sleep disorders is a challenge in individuals with dementia. A precondition for treatment success is thorough diagnostics of sleep disorders. Sleep diaries and observational questionnairs represent important diagnostic tools. In addition to general treatment strategies including optimal treatment of comorbidities, behavioral therapy is a main intervention. Drugs for the treatment of a sleep disorder should only be prescribed with a clear indication and prolongation of prescription should regularly be checked. The active search for and the treatment of sleep disorders should always be performed in individuals with dementia.