Movement disorders and depression due to flunarizine and cinnarizine

Cinnarizine- and flunarizine-associated movement disorder: a literature review

Introduction

Cinnarizine (CNZ) and flunarizine (FNZ) belong to the calcium channel blockers class of medication.

Main text

The aim of this literature review is to evaluate the clinical epidemiological profile, pathological mechanisms, and management of CNZ/FNZ-associated movement disorder (MD). Relevant reports in six databases were identified and assessed by two reviewers without language restriction. One hundred and seventeen reports containing 1920 individuals who developed a CNZ/FNZ-associated MD were identified. The MD encountered were 1251 parkinsonism, 23 dyskinesias, 11 akathisia, 16 dystonia, and 5 myoclonus, and in the group not clearly defined, 592 extrapyramidal symptoms, 19 tremors, 2 bradykinesia, and 1 myokymia. The predominant sex was female with a percentage of 72.69% (466/641). The mean age was 74.49 (SD, 7.88) years. The mean CNZ dose was 148.19 mg (SD, 42.51) and for the FNZ dose, 11.22 mg (5.39). The mean MD onset and recovery were 1.83 years (SD, 1.35) and 3.71 months (SD, 1.26). In the subgroup of subjects that had improvement of the symptoms, the complete recovery was achieved within 6 months of the drug withdrawal in almost all subjects (99%). The most common management was drug withdrawal. A complete recovery was observed in 93.77% of the patients (437/466).

Conclusions

CNZ/FNZ-associated MD was extensively reported in the literature. Parkinsonism was the most well described. Myoclonus (MCL) was the poorest described MD with missing data about the neurological examination and electrodiagnostic studies. The knowledge of this disorder probably can contribute to the understanding of the other drug-induced MDs.

Flunarizine Induced Parkinsonism in Migraine Group: A Nationwide Population-Based Study

Background: Flunarizine (Fz) is a first-line prophylactic medication that is widely used in migraine. However, Fz has been recognized as a potential cause of drug-induced parkinsonism for a long time. However, to our knowledge, there has been no population-based subgroup analyses for Fz-induced parkinsonism (FIP) in migraine patients. Methods: Data were obtained from the Taiwan's National Health Insurance Research Database. The study comprised 6,470 migraine patients who were divided into two groups, based on their exposure or non-exposure to Fz. Results: During the study period (2000-2012), the incidence rate of parkinsonism was 1.92 and 8.72 per 1,000 person-years in the control and Fz -treated groups, respectively. In the study population, the adjusted hazard ratio was 4.07 (95% confidence interval CI: 2.84-5.85). In 45-64-year old subjects and ≥ 65-year old subjects, the risk of FIP was 3.18 times (95% CI = 1.63-6.20) and 4.89 times (95% CI = 3.09-7.72) more than that in the controls. The Fz-treated subjects with comorbidities also had a higher risk (4.54, 95% CI: 3.14-6.57). An average annual cumulative Fz dose > 445 mg was accompanied by the greatest risk of FIP; Fz use for >60 days is a cut-off point for predicting future FIP. Conclusion: At the population level, this study showed a complete picture of FIP in migraine patients. FIP is associated with older age, history of comorbidities, exposure to high-dose of Fz, and longer duration of exposure to Fz.

MDS evidence-based review of treatments for essential tremor

BACKGROUND

Essential tremor is one of the most prevalent movement disorders. Many treatments for essential tremor have been reported in clinical practice, but it is uncertain which options have the most robust evidence. The International Parkinson and Movement Disorder Society commissioned a task force on tremor to review clinical studies of treatments for essential tremor.

OBJECTIVES

To conduct an evidence-based review of current pharmacological and surgical treatments for essential tremor, using standardized criteria defined a priori by the International Parkinson and Movement Disorder Society.

METHODS

We followed the recommendations of the International Parkinson and Movement Disorder Society Evidence Based Medicine Committee.

RESULTS

Sixty-four studies of pharmacological and surgical interventions were included in the review. Propranolol and primidone were classified as clinically useful, similar to Topiramate, but only for doses higher than 200 mg/day. Alprazolam and botulinum toxin type A were classified as possibly useful. Unilateral Ventralis intermedius thalamic DBS, radiofrequency thalamotomy, and MRI-guided focused ultrasound thalamotomy were considered possibly useful. All the above recommendations were made for limb tremor in essential tremor. There was insufficient evidence for voice and head tremor as well as for the remaining interventions.

CONCLUSION

Propranolol, primidone, and topiramate (>200 mg/day) are the pharmacological interventions in which the data reviewed robustly supported efficacy. Their safety profile and patient preference may guide the prioritization of these interventions in clinical practice. MRI-guided focused ultrasound thalamotomy was, for the first time, assessed and was considered to be possibly useful. There is a need to improve study design in essential tremor and overcome the limitation of small sample sizes, cross-over studies, short-term follow-up studies, and use of nonvalidated clinical scales. © 2019 International Parkinson and Movement Disorder Society.

Flunarizine related movement disorders: a nationwide population-based study

Flunarizine (fz) causes side effects such as movement disorders (MDs). We investigated risk factors associated with fz-related MDs. Participants were recruited from the longitudinal health insurance databases and included patients who took fz for more than 1 month. Patients with one of the underlying diseases, or with concomitant drug use (antipsychotics, metoclopramide or reserpine), and those diagnosed with MDs before fz use were excluded. Fz-related MD was defined as a new diagnosis of parkinsonism or hyperkinetic syndrome including dyskinesia or secondary dystonia during fz use or within 3 months after drug discontinuation. After exposure, 288 individuals had fz-related MDs (parkinsonism, n = 240; hyperkinesia, n = 48). Risk factors associated with these disorders were higher-dose exposure (cumulative defined daily dose [cDDD] ≥87.75, odds ratio [OR]: 3.80; 95% CI: 2.61–5.52), older age (OR: 1.07; 95% CI: 1.06–1.09), history of essential tremor (OR: 6.39; 95% CI: 2.29–17.78) and cardiovascular disease (CVD) (OR: 1.47; 95% CI: 1.14–1.9). The optimal value of cDDD to predict MDs was 58.5 (sensitivity: 0.67, specificity: 0.60), indicating an overall exposure of 585 mg. Higher exposure dose and duration, older age, history of essential tremor, and CVD were associated with fz-associated MDs. Clinicians ought to watch for extrapyramidal side effects when prescribing fz.

Flunarizine and the risk of parkinsonism in a newly diagnosed type 2 diabetic population in Taiwan: A nested case-control study

Previous studies demonstrated that both diabetes and flunarizine use can increase the risk of parkinsonism. The aim of the current study was to investigate the risk of developing parkinsonism after flunarizine treatment, in a cohort of patients newly diagnosed with type 2 diabetes. We conducted a nested case-control study of a type 2 diabetic cohort from the Taiwan Longitudinal Health Insurance Database 2005 (LHID 2005). Each incident case of parkinsonism, during the period from 2001 to 2013, was randomly matched with 3-10 controls, according to age, sex, calendar year of cohort entry, and the duration of follow-up. Conditional logistic regression was used to estimate the odds ratio (OR) of parkinsonism associated with flunarizine use. The cohort consisted of 44,644 patients with newly diagnosed type 2 diabetes from 2001 to 2013, of whom 464 patients had a parkinsonism event during the follow-up period. The adjusted OR of parkinsonism with relation to flunarizine use was 2.75 (95% confidence interval: 2.26-3.36). There were also duration- and dose-response effects. Compared to those who had not used it, the OR for developing parkinsonism was 1.77 for patients who used flunarizine for less than 1 month. When the exposure period expanded over 3 months, the OR increased to 7.03. Our findings suggested that flunarizine use is a potential risk factor for parkinsonism in patients with newly diagnosed type 2 diabetes, especially when the drug is persistently used for over 3 months.

Extrapyramidal symptoms after exposure to calcium channel blocker-flunarizine or cinnarizine

Purpose

Flunarizine (fz) and cinnarizine (cz) have well-known extrapyramidal side effects (EPSEs). The aim of this study was to evaluate the incidence and occurrence time of cz- and fz-related EPSEs.

Method

Patients who took fz or cz for more than 1 month were identified from the longitudinal health insurance database 2005 and 2010. Excluded were patients with any of the underlying diseases that may cause parkinsonism. Drug-induced EPSEs were defined as the new diagnosis of parkinsonism, dyskinesia, or secondary dystonia during drug use or within 3 months after discontinuing the medication. Age- and sex-matched controls were included in this study.

Results

Recruited for analysis were individuals who took fz (n = 26,133) and cz (n = 7186). The incidence rates of fz- and cz-induced EPSEs were 21.03 and 10.3 per 10,000 person-months, respectively. The hazard ratios (HRs) of EPSEs among fz and cz subjects were 8.03 (95% CI 6.55–9.84) and 3.41 (95% CI 2.50–4.63) when compared with the control individuals. Both fz and cz patients had a higher cumulative incidence of EPSEs than their control individuals (p < 0.001). Among subjects who took fz, the incidence of EPSEs was higher in the second than first year of drug exposure (45.59 vs 21.03 per 10,000 person-months).

Conclusions

Fz and cz significantly increased the risk of parkinsonism, dyskinesia, and dystonia. Potential benefits and risks should be weighed when considering long-term use of these drugs especially fz.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-017-2247-x) contains supplementary material, which is available to authorized users.

Not all drug-induced parkinsonism are the same: the effect of drug class on motor phenotype

Drug-induced parkinsonism (DIP) is classically described as acute/subacute, bilateral symmetric syndrome in which tremor is infrequent compared to Parkinson's disease. Most DIP cases are caused by classic (CN) and second-generation neuroleptics (SN), and calcium channel blockers (CCB). We evaluated potentially distinctive demographic and clinical features in DIP among different drug classes. This was a prospective study of reversible DIP related to single selected drugs on each class. Baseline assessment included demographic, clinical data, and scales for staging, severity of motor signs of parkinsonism, tremor, and other involuntary movements. Six months after medication withdrawal, patients were reassessed. Those with no parkinsonian signs were included in the final sample. 157 cases were included after strict criteria were applied. Most common agents were haloperidol, levomepromazine, and chlorpromazine for the CN-DIP group, flunarizine and cinnarizine for the CCB-DIP group, and risperidone and olanzapine for the SN-DIP group. Drug exposure was shorter for CN-DIP cases; duration of parkinsonism was longer in the CCB-DIP group. CN-DIP had worse bradykinesia, rigidity, axial, total motor, and disease stage scores, with higher frequency of rigid-akinetic parkinsonism. Tremor scores were worse for CCB-DIP cases. SN-DIP presented as a less severe but similar form of CN-DIP. Tardive-type involuntary movements were less common in the SN-DIP group. DIP profile differs significantly depending on drug class involved, not only in terms of severity, but also regarding the differential combination of signs. These findings may help guiding clinicians in screening and diagnosing DIP in patients exposed to these drugs.

Depressogenic medications and other risk factors for depression among Polish patients with epilepsy

PURPOSE

The aim of this study was to assess the prevalence of depression among patients with epilepsy and to establish the risk factors of depression in that group, with special focus on the use of potentially depressogenic medications.

PATIENTS AND METHODS

We studied 289 consecutive patients who visited epilepsy outpatient clinic (University Hospital of Krakow) and met inclusion criteria. All patients were screened with Beck Depression Inventory (BDI), and those with BDI score ≥12 were further evaluated by a psychiatrist.

RESULTS

Mean age of patients was 35.7 years, and mean duration of epilepsy was 14.7 years. Idiopathic generalized epilepsy was diagnosed in 63 patients (21.8%), focal epilepsy was found in 189 subjects (65.4%), and unclassified epilepsy was diagnosed in 37 patients (12.8%). Frequent seizures (>1 per month) were reported in 107 patients (37.0%). Thirty-five patients (12.1%) reported an ongoing treatment with one or more of the predefined potentially depressogenic medication (β-blockers, combined estrogen and progestogen, corticosteroid, or flunarizine). In a group of 115 patients (39.8%) who scored ≥12 points in BDI, depression was finally diagnosed in 84 subjects (29.1%) after psychiatric evaluation. Only 20 of those patients (23.8%) were treated with antidepressant. Independent variables associated with the diagnosis of depression in the logistic regression model included frequent seizures (odds ratio [OR] =2.43 [95% confidence interval, 95% CI =1.38-4.29], P=0.002), use of potentially depression-inducing medications (OR =3.33 [95% CI =1.50-7.39], P=0.003), age (OR =1.03 [95% CI =1.01-1.05] per year], P=0.005), and use of oxcarbazepine (OR =2.26 [95% CI =1.04-4.9], P=0.038).

CONCLUSION

The prevalence of depression among consecutive Polish patients with epilepsy reached 29.1%. Less than quarter of them received antidepressant treatment at the moment of evaluation. Independent variables associated with depression included age, frequent seizures, and the use of oxcarbazepine or predefined depressogenic medications.

Efficacy and safety of cinnarizine in the prophylaxis of migraine in children: a double-blind placebo-controlled randomized trial

BACKGROUND

In spite of the high occurrence of migraine headaches in school-age children, there are currently no approved and widely accepted pharmacologic agents for migraine prophylaxis in children. Our previous open-label study in children revealed the efficacy of cinnarizine, a calcium channel blocker, in migraine prophylaxis. A placebo-controlled trial was conducted to demonstrate the efficacy and safety of cinnarizine in the prophylaxis of migraine in children.

TRIAL DESIGN

A double-blind, placebo-controlled, parallel-group study conducted in a tertiary medical center in Tehran, Iran.

METHODS

Children (5-17 years) who experienced migraines with and without aura, as defined on the basis of 2004 International Headache Society criteria, were recruited into the study. Children were excluded if they had complicated migraine, epilepsy, or a history of use of migraine prophylactic agents. Each participant was randomly assigned to receive cinnarizine (a single 1.5 mg/kg/day dose in children weighing less than 30 kg and a single 50 mg dose in children weighing more than 30 kg, administered at bedtime) or placebo. The frequency, severity, and duration of headaches over the trial period were assessed and adverse effects were monitored.

RESULTS

A total of 68 children (34 in each group) with migraine were enrolled and 62 participants completed the study. After 3 months of taking cinnarizine or placebo, children in both groups experienced significantly reduced frequency, severity, and duration of headaches compared with baseline measurements (P < 0.001). However, compared with 31.3% of children in the placebo group, 60% of children in the cinnarizine group reported more than 50% reduction in monthly headache frequency (P = 0.023), suggesting that cinnarizine was significantly more effective than placebo in reducing the frequency of headaches. No serious adverse effects of the medications were observed in the treated children, including no abnormal weight gain or extrapyramidal signs.

CONCLUSION

Our results indicate that the use of cinnarizine at doses administered in this study is effective and safe for prophylaxis of migraine headaches in children.

Drug-induced parkinsonism

INTRODUCTION

Drug-induced parkinsonism (DIP) is the second most common cause of parkinsonism after idiopathic Parkinson's disease (iPD). Initially reported as a complication of antipsychotics, it was later recognized as a common complication of antidepressants, calcium channel antagonists, gastrointestinal prokinetics, antiepileptic drugs and many other compounds. Despite being a major health problem in certain populations, it seems to be frequently overlooked by the medical community.

AREAS COVERED

This paper approaches the concept of DIP, reviews its epidemiology, clinical features and ancillary tests recommended for a correct diagnosis. The authors discuss the different drugs and its pathogenic mechanisms. The relevance of an early recognition and recommendations for a correct management are commented.

EXPERT OPINION

Prescribers need to remain vigilant for DIP, particularly in the elderly, patients taking multiple drugs and those with genetic risk factors involved in iPD. Cessation of the causing agent is the main treatment and there is no evidence of benefit for the use of anticholinergics or levodopa. If the medication cannot be withdrawn, it should be switched to agents with a lower risk of DIP.

Depressogenic effects of medications: a review

The literature is filled with reports that link medications with the onset or progression of depression. Because depression is so common in patients with medical illness, assessing whether a medication has in fact caused depression, or whether the relationship is coincidental, can be challenging. In this article, we review the literature on the association between medications and depression. For most agents, there are case reports or small studies linking the medication with the onset of depression, but more rigorous prospective studies are either lacking or found no association between the agent and depression. However, several medications, (eg, barbiturates, vigabatrin, topiramate, flunarizine, corticosteroids, mefloquine, efavirenz, and interferon-α) do appear to cause depression in some patients and should be used with caution in patients at risk for depression.

Drug-induced parkinsonism in the elderly

Drug-induced parkinsonism is primarily caused by drugs that interfere with dopamine stimulation. Antipsychotic drugs are the most common offenders, but drug-induced parkinsonism may be seen with many other drugs, such as antiemetics and certain calcium-channel blockers. These medications are widely used in the elderly. Unlike the first generation of antipsychotic drugs, all of which cause parkinsonism and other extrapyramidal side effects, atypical antipsychotics have motor side effects that are not uniform. Among the atypicals, only quetiapine and clozapine are not associated with drug-induced parkinsonism. Since drug-induced parkinsonism is frequently under-recognized, it may be devastating in an elderly person with already compromised gait.

Drug-induced parkinsonism

Drug-induced parkinsonism (DIP) is the second cause of akinetic rigid syndrome in the Western world and its prevalence is increasing and approaching that of idiopathic Parkinson's disease due to the ageing of the population and to the rising of polypharmacotherapy. DIP was initially reported as a complication of neuroleptics in psychiatric patients, but it has also been described with a great diversity of compounds such as antiemetics, drugs used for the treatment of vertigo, antidepressants, calcium channel antagonists, antiarrythmics, antiepileptics, cholinomimetics and other drugs. Although traditionally considered reversible, DIP may persist after drug withdrawal. At least 10% of patients with DIP develop persistent and progressive parkinsonism in spite of the discontinuation of the causative drug. Irreversible or progressive DIP has been considered as an indication of presymptomatic parkinsonian deficit, unmasked but not caused by the offending drug, but it could be explained by persistent toxicity of the responsible pharmacological agents on the nigrostriatal dopamine pathway. The best treatment of DIP is prevention, including the avoidance of prescription of causative drugs whenever it is not strictly necessary. In patients who require potentially risky medication, it is necessary to perform adequate monitoring for early parkinsonian deficits and early discontinuation if these deficits appear. Atypical neuroleptics are associated with lower risk than first generation antipsychotic drugs. Special precautions are needed in elderly subjects, in patients treated with multiple drugs for prolonged periods of time and in those with familial risk factors including familial parkinsonism or tremor, or in those with genetic variants of genes involved in idiopathic Parkinson's disease.

Tardive Blepharospasm Associated With Cinnarizine Use

OBJECTIVE

To report a patient with chronic blepharospasm possibly induced by the calcium-channel blocker cinnarizine.

CASE REPORT

A 53-year-old woman developed chronic blepharospasm during a prolonged therapy with calcium-channel blocker cinnarizine for the treatment of vertigo.

CONCLUSIONS

"Tardive blepharospasm" should be considered as a possible adverse effect of cinnarizine.

[Drug-induced parkinson syndromes]

Parkinsonism is defined by the association of akinesia with one of the following symptoms: extrapyramidal rigidity, tremor at rest, or postural instability. A drug-induced aetiology must always be suspected when parkinsonian symptoms appear, or increase in a patient receiving drug treatment. Indeed drug-induced is the more frequent aetiology of secondary parkinsonism. The main treatments involved are antipsychotic and other neuroleptic drugs (accounting for up to two-thirds of drug-induced parkinsonism), and calcium-channel entry blockers. The risk associated with antipsychotics is often dose dependent and related to dopamine D2 striatal receptor occupancy induced by the antipsychotic drug. This risk is inferior for the second generation antipsychotics. The other treatments more rarely involved are antidepressants (tricyclic and selective serotonin reuptake inhibitors), lithium, valproic acid, and others. The main criterium for imputability is chronological, regression of symptoms being observed in 40-74% of cases, after a mean delay of 3 months from cessation of treatment. However, 15% of cases persist after drug withdrawal, leading to a diagnosis of underlying idiopathic Parkinson's disease.

Flunarizine and cinnarizine-induced parkinsonism: a historical and clinical analysis

BACKGROUND

Drug-Induced Parkinsonism (DIP) represents the second leading cause of Parkinsonism (PK) in several countries. Flunarizine and cinnarizine are some of the most common drugs that cause DIP. This paper reviews the first description of Flunarizine and Cinnarizine-Induced Parkinsonism (FCIP), as well as the subsequent literature, emphasizing epidemiological, clinical and diagnostic aspects.

METHODS

We reviewed the literature on the subject, with special emphasis on the first description and the later definition of the clinical syndrome that results from chronic use of flunarizine and cinnarizine.

RESULTS

In 1984, De Melo-Souza reported the first description of flunarizine-induced PK in five patients. Other reports followed on FCIP, emphasizing the clinical features, which are symmetrical parkinsonism, and depression, affecting mainly elderly women.

CONCLUSIONS

Eighteen years after the original description, FCIP is a recognized condition with specific clinical features, and is the second most common cause of parkinsonism in many countries.

Normalization of high interictal cerebrovascular reactivity in migraine without aura by treatment with flunarizine

BACKGROUND

Modification of migraine-associated cerebrovascular reactivity may provide insight into the mechanism of action of a given therapeutic intervention.

METHODS

With transcranial Doppler and a breath-holding index, cerebrovascular reactivity to hypercapnia was evaluated in 20 patients with migraine without aura interictally and in 11 healthy controls. Patients were started on prophylactic treatment with flunarizine 10 mg per day, and measurements were repeated at the end of every month for 3 months. Headache status was evaluated clinically via a headache index. Headache index; breath-holding index; systolic, diastolic, and mean blood flow velocities; and pulsatility index measurements were recorded at every session.

RESULTS

The baseline breath-holding index was significantly higher in the migraine group compared to the control group (P =.002). No difference in other parameters was found between the groups. The change in the headache index was significant (P<.001), indicating a beneficial effect from flunarizine. The breath-holding index improved significantly after treatment (P<.001), and the baseline difference in the breath-holding index between the pretreatment migraine group and the control group was no longer evident at 3 months. There was no significant change with treatment in the other transcranial Doppler parameters.

CONCLUSIONS

Our finding of unchanged blood flow velocities but normalized cerebrovascular reactivity after treatment suggests that the mechanism of action of flunarizine in migraine does not involve a vasodilatory effect on cerebral vessels. It may be instead that flunarizine modifies cerebrovascular reactivity through its action on centrally located structures that subserve autonomic vascular control.

Pharmacological involvement of the calcium channel blocker flunarizine in dopamine transmission at the striatum

Single intrastriatal microinjections of 25, 50 and 100nmol/microl of flunarizine in normal rats produced a dose-dependent turning behavior toward the injected side when they were challenged with apomorphine (1mg/kg, s.c). This effect was seen at 1, 3 and 7 days following administration of the high dose of flunarizine, but had subsided by 24h after administration of the intermediate dose; the low dose was ineffective. However, intrastriatal injection of the high dose of flunarizine resulted in a local lesion and thereafter this dose was not used. A similar dose-response relationship was determined for nifedipine, an L-type calcium channel antagonist. Injection of this antagonist did not result in apomorphine-elicited rotational behavior, reflecting its lack of antidopaminergic action. Intrastriatal injections of haloperidol (5microg/microl), an antagonist of dopamine D(2) receptors, or the sodium channel blocker lidocaine (40microg/microl), were given in order to compare their effects to those observed with flunarizine. Intracerebral injection of haloperidol produced ipsilateral turning in response to systemic administration of apomorphine given 60min after. The same response was obtained with the injection of apomorphine 10min after the injection of intracerebral lidocaine. This effect was no longer apparent 24h after the microinjection of haloperidol and 60min after the injection of lidocaine. In rats rendered hemiparkinsionian by lesioning the nigrostriatal pathway with 6OHDA, intrastriatal microinjection of flunarizine (50nmol/microl) significantly reduced apomorphine (0.2mg/kg, s.c.)-elicited turning behavior towards the non-lesioned side. These results suggest an antidopaminergic effect of flunarizine mediated by antagonistic action of post-synaptic striatal dopamine receptors. However, an action of the drug on sodium channels may not be ruled out. These studies offer additional supporting evidence for the induction or aggravation of extrapyramidal side-effects in patients receiving flunarizine.

Calcium channel agonists and dystonia in the mouse

Systemic administration of the L-type calcium channel agonists +/-Bay K 8644 or FPL 64176 causes a characteristic pattern of motor dysfunction in normal C57BL/6J mice that resembles generalized dystonia. There is no associated change in the electroencephalogram, confirming that the motor disorder does not reflect epileptic seizures. However, the electromyogram reveals an increase in baseline motor unit activity with prolonged phasic discharges consistent with dystonia. The duration and severity of dystonia is dependent on the dose administered and the age of the animal at testing. The effects are transient, with the return of normal motor behavior 1-4 hours after treatment. Similar effects can be provoked by intracerebral administration of small amounts of the drugs, indicating a centrally mediated response. Dystonia can be attenuated by co-administration of dihydropyridine L-type calcium channel antagonists (nifedipine, nimodipine, and nitrendipine) but not by non-dihydropyridine antagonists (diltiazem, verapamil, and flunarizine). These results implicate abnormal function of L-type calcium channels in the expression of dystonia in this model.

Evidence of sex related differences in the effects of calcium channel blockers on neuroleptic-induced catalepsy in mice

1. Calcium channel blockers (CCBs) are reported to affect extrapyramidal motor behavior in mammals. Since sex related differences are a common feature in the pharmacological properties of several centrally active drugs, the authors decided to investigate the effects of verapamil (VER), flunarizine (FLU) and nimodipine (NIM), three pharmacologically different CCBs, on neuroleptic-induced catalepsy in male and female albino mice. 2. Catalepsy was induced with haloperidol (0.75 mg/kg, i.p.) and measured at 30-min intervals by means of a bar test. Drugs (or appropriate vehicle, for the controls) were injected i.p. 20 min before haloperidol, with each animal being used only once. 3. VER (1, 5 and 10 mg/kg) did not significantly affect catalepsy in male mice. In females, however, a significant attenuation of catalepsy was found at the two higher doses. 4. FLU (1, 5 and 10 mg/kg) did not significantly affect catalepsy in male mice, whilst a significant attenuation was observed in females with the doses of 1 and 5 mg/kg (but not with the dose of 10 mg/kg). 5. NIM (3, 10 and 30 mg/kg) potentiated neuroleptic-catalepsy in males at the doses of 10 and 30 mg/kg. In females, however, only the higher dose of NIM caused a potentiation of catalepsy. 6. These results demonstrate the existence of sex related differences in the extrapyramidal effects of CCBs in mice. Further, this sex related effect might depend, among other factors, on the particular channel involved.

Does the antimigraine action of flunarizine involve the dopaminergic system? A clinical-neuroendocrinological study

We have investigated the prolactin response to bromocriptine (BRC), a D2 dopamine receptor agonist in migrainous women before and after treatment with flunarizine. We evaluated whether this test was predictive of therapeutic efficacy of flunarizine treatment and whether the therapeutic response to flunarizine treatment was related to its effect on dopaminergic system at tuberoinfundibular level. Ten migrainous women underwent a BRC test in the late follicular phase before and after 1 and 3 months of treatment with flunarizine 10 mg at bedtime. Blood samples of prolactin (PRL), growth hormone, follicle-stimulating hormone, luteinizing hormone, estradiol and progesterone were taken at basal condition. PRL was also evaluated 1 and 2 h after BRC (2.5 mg) administration. Each patient kept a daily headache diary for 1 month prior to the test and throughout the study. The level of PRL inhibition after BRC administration, observed before flunarizine treatment, was not predictive of the therapeutic response observed after 1 and 3 months of treatment. The effect of flunarizine on PRL level was not related to the therapeutic efficacy of the drug. These data suggest that flunarizine does not attenuate the activity of dopaminergic neurons in migrainous patients, and that the antimigraine effect of flunarizine does not seem related to its action on dopaminergic system at least at tuberoinfundibular level.

Cinnarizine-induced parkinsonism: ten years later

A retrospective study was carried out to investigate the evolution of patients diagnosed with cinnarizine-induced parkinsonism (CIP) over the past 15 years. A total of 74 cases of CIP were found among 172 patients with drug-induced parkinsonism (DIP). Both CIP and other DIP were significantly more frequent in women. No clinical differences between CIP and other DIP were found. Most of the patients (66 of 74) completely recovered after cinnarizine withdrawal in 1-16 months. Eleven patients later developed Parkinson's disease; four of them had previously recovered. Five patients had tardive dyskinesia. CIP accounts for a high proportion of DIP referred to neurologists in populations in which cinnarizine is widely prescribed. The symptoms typically resolve after drug withdrawal, although complete recovery may take more than 1 year.

Drug-induced movement disorders

Drug-induced movement disorders are often unrecognized, especially when not due to dopamine receptor blockers. This review discusses acute, subacute, and chronic syndromes. Pathophysiology relates almost always to dopaminergic transmission. Patient-dependent vulnerability and drug-dependent sensitivity are contributing factors. Young patients are more prone to acute reactions, and tardive or chronic conditions are more frequent in the elderly. Subclinical Parkinsonism can be unmasked by medication exposure. Treatment of tardive dyskinesia remains a challenging task for the clinician, but novel antipsychotics and dopamine depleting agents can be beneficial.

A postmarketing study of flunarizine in migraine and vertigo

This prospective, open multi-centre study on flunarizine focused on the risk/benefit ratio of the use of flunarizine in the prophylaxis of migraine and in the treatment of vertigo, due to disorder of the vestibular system. The assessment of risks focused on the incidence of new events of depression and/or extrapyramidal syndrome during flunarizine treatment. For migraine, flunarizine was compared to propranolol in 686 patients; for vertigo, flunarizine was compared to betahistine in 198 patients. The incidence of depression during follow-up in this study was significantly higher in the flunarizine group than in the propranolol group in the condition of migraine. There were no observations of an extrapyramidal syndrome. There was a suggestion that flunarizine has more benefits than propranolol in the condition of migraine, and that betahistine has more benefit than flunarizine in the condition of vertigo. Differences in dosages could possible explain these differences.

Prevalence of Parkinson's disease in Junín, Buenos Aires Province, Argentina

We investigated the prevalence of Parkinson's disease (PD) in a South American city: Junín, Buenos Aires Province, Argentina. At dwellings systematically selected, the case finding involved household screenings and neurological examinations (i.e., a two-phase survey approach). Only persons 40 years of age or older were eligible (N = 7,765). There were 51 cases of PD identified, yielding a crude prevalence of 656.8 per 100,000 population. The age-specific prevalence was consistently higher in men than women, and it increased with advancing age for both sexes. In addition to prevalence figures. we present tallies related to clinical features of PD, as well as tallies related to other subtypes of parkinsonism.

A long-term follow-up study of cinnarizine- and flunarizine-induced parkinsonism

The natural course of calcium-entry blocker-induced parkinsonism was evaluated in 13 elderly patients previously exposed to cinnarizine or flunarizine or both for a median period of 7 months. Clinical assessments were carried out before drug discontinuation and twice thereafter over a period lasting < or = 7 years. None of the patients showed a full recovery of extrapyramidal signs, indicating that the long-term prognosis of the parkinsonism is less benign than previously reported. Two main patterns of clinical outcome were recognized (i.e., "remittent" and "persistent and not progressive" parkinsonism), whereas the development of a progressive disorder was observed only in one patient. No significant correlation was found between the patterns of outcome and some clinical variables, such as total duration of exposure to cinnarizine and flunarizine, cumulative drug dosages, and age at onset of parkinsonism. There was no significant difference in terms of family history of essential tremor or parkinsonism or both among patients with the two main patterns of clinical course.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity in non-human primates is antagonized by pretreatment with nimodipine at the nigral, but not at the striatal level

The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been shown to induce parkinsonism in man and non-human primates. Hypotheses concerning the mechanism of action of MPTP have been related to the pathogenesis of nigral cell death in Parkinson's disease. For instance, alterations of calcium influxes have been reported to be implicated in both MPTP-induced parkinsonism and Parkinson's disease. Recently, we reported that nimodipine, a blocker of L-type calcium channels, prevents dopaminergic MPTP-induced neurotoxicity in C57B1/6 black mice. The present study extended these rodent findings to the non-human primate model of Parkinson's disease and assessed the effects of nimodipine, continuously applied by pellet for 18 days, on behavioural, biochemical and histological parameters, following systemic application of MPTP in common marmosets (Callithrix jacchus). The experimental design involved five groups of common marmosets and a total of 24 animals. Monkeys assigned to group I (n = 4) received subcutaneously implanted vehicle pellets 7 days prior to subcutaneous saline injections (control). Monkeys of group II (n = 4) were treated with nimodipine pellets (80 mg) and saline injections. Marmosets in group III (n = 8) were treated with vehicle pellets and received 4 times MPTP (MPTP-HCl, 2 mg/kg body weight subcutaneously, separated by an interval of 24 h for a total of 4 days). Monkeys in group IV (n = 4) and V (n = 4) were treated as group-III animals except for the implantation of nimodipine pellets (80 mg and 120 mg, respectively) 7 days prior to toxin exposure. In common marmosets MPTP induced severe parkinsonian symptoms, a pronounced dopamine depletion in the caudate-putamen (more than 99% of control) and a loss of tyrosine hydroxylase immunoreactive cells in the substantia nigra (50% percent of control) 7 days after MPTP-administration. Pretreatment with nimodipine (120 mg pellets) did neither attenuate the behavioural impairments in MPTP-treated animals nor antagonize the striatal neurotoxin-induced dopamine depletion, but almost completely prevented (in a dose-dependent manner) the MPTP-induced decrease of nigral tyrosine hydroxylase immunoreactive cells. These data suggest that application of nimodipine, during the observation period of 7 days, protects against MPTP-induced neurotoxicity in common marmosets at the cellular nigral level, but not at the synaptic striatal level, implicating differential mechanisms of actions of MPTP-induced neurotoxicity at the nigral versus the striatal level.

Post-marketing cohort study comparing the safety and efficacy of flunarizine and propranolol in the prophylaxis of migraine

A comparative post-marketing surveillance study of the safety and efficacy of flunarizine and propranolol in the treatment of migraine was carried out. General practitioners in Belgium and the Netherlands each recruited patients for whom they would prescribe one of the study medications in the normal course of their treatment and recorded all medical events on follow-up forms for up to 8 months. A total of 1601 migraine patients were enrolled; 838 in the flunarizine cohort and 763 in the propranolol cohort. Propranolol was somewhat better than flunarizine in reducing the severity of migraine attacks, although this may have been due to a selection bias. Discontinuations of therapy due to events considered likely to be treatment-related were mostly due to the recognized side effects of the two drugs. As regards the occurrence of depressions, a total of 58 patients had depressive events, 34 in the flunarizine cohort and 24 in the propranolol cohort. Whereas migraine itself appears to be associated with an increased risk of depression, the number of previous migraine treatments was shown to be an additional risk factor for the development of depression in patients receiving flunarizine as was a history of depression. Overall, there was no appreciable difference in the risk/benefit ratio between flunarizine and propranolol.

Hemiatrophy, juvenile-onset exertional alternating leg paresis, hypotonia, and hemidystonia and adult-onset hemiparkinsonism: the spectrum of hemiparkinsonism-hemiatrophy syndrome

A 45-year-old woman with a history of probable perinatal craniocerebral trauma resulting in mild asymptomatic right hemiatrophy developed right leg weakness and hypotonia alternating with dystonia only after prolonged exertion at age 12. At age 27, she developed right-sided parkinsonism. Exertional paresis and dystonia and parkinsonism responded completely to levodopa; however, she developed a progressive reduction in the duration of action of levodopa over the first 4 years of treatment. Investigations including computed tomography, magnetic resonance imaging, [18F]fluorodopa, and [18F]fluorodeoxyglucose positron emission tomography scans suggested a static lesion involving the left substantia nigra. This unusual exertion-induced weakness and hypotonia alternating with hypertonia and dystonia has not been reported previously. The role of dopamine deficiency in dystonia and the role of levodopa in the development of fluctuations in Parkinson's disease are discussed. Review of the literature, including this patient, emphasizes the heterogeneity of the syndrome of hemiparkinsonism-hemiatrophy.

D2 receptor blockade by flunarizine and cinnarizine explains extrapyramidal side effects. A SPECT study

Twenty-six patients under treatment with the calcium channel blockers flunarizine (Fz) or cinnarizine (Cz) were examined-with single-photon emission computed tomography using [123I]iodobenzamide as a ligand. The striatal dopamine D2 receptor-binding potential was determined and found to be reduced by 14 to 63% (39.5 +/- 15.0%; p < 0.0001) in patients compared with age-matched control values. This reduction was larger in 12 patients with extrapyramidal symptoms and was only slowly reversible after discontinuation of treatment. Patients treated for > 6 months had significantly larger reductions than patients treated for a shorter period. Parkinsonian symptoms were only seen in patients older than 50 years. Our findings prove a neuroleptic-like action of Fz and Cz, which seems to be the major reason for their extrapyramidal side effects. Older age and long-term treatment are predisposing factors for these effects.

Extrapyramidal symptoms associated with calcium-channel blockers

Flunarizine and cinnarizine have been well documented to cause EPS. Other CCBs, on rare occasions, also have been reported to cause EPS. Theoretical explanations for these events include the inhibition of calcium influx into striatal cells and direct dopaminergic antagonistic properties. In addition, the chemical structures of flunarizine and cinnarizine, which are related to neuroleptics, may explain the relatively greater incidence of EPS with these agents. Suggested risk factors for acquiring EPS with flunarizine or cinnarizine use appear to be age, although experience with using these agents in younger patients is limited, and a family history of tremors and/or Parkinson's disease. The onset and type of presentation is unpredictable and, in most instances, discontinuation of the medication relieves the symptoms within a few days to months. Pharmacologic management of EPS with continued use of the offending agent generally has not been of clinical benefit. In conclusion, patients receiving CCBs, particularly flunarizine and cinnarizine, should be monitored for EPS.

Dopamine D2 receptor blockade and antimigraine action of flunarizine

We studied in vivo the influence of flunarizine on dopamine D2 receptors and investigated whether dopamine D2 receptor blockade is involved in its antimigraine action. Eleven migraine patients, treated with flunarizine, 10 mg per day, underwent single photon emission computer tomography (SPECT) using [123I] labeled iodobenzamide, a ligand with high affinity and high specificity for D2 receptors. There was a reduction of the dopamine D2 receptor binding potential in all patients compared to age-matched controls. The efficacy of flunarizine in migraine prophylaxis failed to correlate with the degree of the dopamine D2 receptor blockade. The antimigraine action of flunarizine may not involve antidopaminergic mechanisms.

Drug-induced depression. Incidence, avoidance and management

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R), drug-induced depression may be classified as an Organic Mood Syndrome, Depressed Type. Unfortunately, the DSM-III-R diagnostic criteria are not sufficiently precise for application in research, and studies of drug-induced depression have rarely utilised these criteria. Research concerned with drug-induced depression is characterised by a number of methodological complications. These include differing definitions of depression, including depression defined as a symptom, a syndrome, or by diagnostic criteria for a specific mental disorder. In addition, patients undergoing pharmacological treatments for medical illnesses are typically exposed to considerable psychosocial stress due to the suffering and disability associated with illness. These psychosocial factors may in themselves precipitate episodes of depression. Due to these complicating factors, sophisticated study designs are required to confirm an aetiological role for medications as risk factors for depression. Unfortunately, adequate studies have rarely been conducted, and much of the literature consists of case reports and clinical observations. Consequently, clinicians are frequently required to make clinical judgements about the aetiology of patients' depressive symptoms in the absence of definitive scientific information about the role of drugs. Nevertheless, a knowledge of the relevant literature will assist clinicians in making reasoned judgements about the aetiology, prevention and management of these disorders.

Nimodipine in migraine: clinical efficacy and endocrinological effects

Serum prolactin is increased during chronic flunarizine treatment of patients suffering from migraine. In order to clarify the role of calcium in control of the secretion of anterior pituitary hormones, a study has now been made of the effects of chronic nimodipine and propranolol treatment of migraine patients on prolactin (PRL), luteinizing hormone (LH) and growth hormone (GH) levels. 11 patients were treated with nimodipine and 8 with propranolol for four months. A statistically significant reduction in the frequency of the attacks was demonstrated in both groups. No significant change was found in the hormones levels during nimodipine treatment.

Epidemiological assessment of levodopa use by populations

This study is an analysis of the measurements of drug use by populations proposed by the Nordic Council on Medicines, conducted from an epidemiological-theoretical perspective. Particular attention is given to levodopa use (LDU). Several measurements of comparative LDU are proposed here for the assessment of levodopa (LD) consumption, from data on LD sales to well defined populations, over known periods of time. The method takes into account possible purposes of LDU evaluations, and is based on a reported model which combines information on Parkinson's Disease prevalence (PD) from surveys, gross levodopa sales, age-structure of the population, the figures for infant mortality rates (IMRs) taken as an indicator of modernization, and the average amount of LD prescribed as daily dose. The evaluation of LDU is implemented following a stepwise procedure.

Flunarizine. A reappraisal of its pharmacological properties and therapeutic use in neurological disorders

Flunarizine is a class IV calcium antagonist with a pharmacological profile which suggests its therapeutic potential in a number of neurological and cerebrovascular disorders. It is an effective prophylactic treatment for common or classic migraine in children and adults, and it appears at least as effective as a number of other agents which act by different pharmacological mechanisms, including pizotifen (pizotyline), cinnarizine, methysergide, nimodipine, metoprolol, propranolol, aspirin and cyclandelate. Flunarizine is also effective in reducing the frequency of seizures, when used as an 'add-on' treatment, in some patients with partial or generalised epilepsy resistant to maximal therapy with a combination of several conventional antiepileptic drugs. Placebo-controlled studies show that flunarizine is effective in the treatment of vertigo and associated symptoms of either peripheral or central origin, and in the treatment of cerebrovascular insufficiency where psychological symptoms, rather than vertigo, are the primary symptoms. In the treatment of vertigo, flunarizine appears at least as effective as cinnarizine and more effective than nicergoline, betahistine dichlorhydrate, pentoxifylline (oxpentifylline) and vincamine. Flunarizine therefore is useful in the prophylaxis of migraine, an effective treatment for vertigo and a worthwhile alternative as 'add-on' therapy in patients with epilepsy resistant to conventional drugs.