Susceptibility to express amphetamine locomotor sensitization correlates with dorsolateral striatum bursting activity and GABAergic synapses in the globus pallidus

Repeated psychostimulant administration results in behavioral sensitization, a process that is relevant in the early phases of drug addiction. Critically, behavioral sensitization is not observed in all subjects. Evidence shows that differential neuronal activity in the dorsolateral striatum (DLS) accompanies the expression of amphetamine (AMPH) locomotor sensitization. However, whether individual differences in DLS activity previous to AMPH administration can predict the expression of locomotor sensitization has not been assessed. Here, we examined DLS neuronal activity before and after repeated AMPH administration and related it to the susceptibility of rats to sensitize. For that, single-unit recordings on DLS medium spiny neurons (MSNs) were carried out in freely moving male Sprague Dawley rats during repeated AMPH administration. We also examined differences in neurostructure that could accompany sensitization. We quantified the density of the inhibitory postsynaptic marker gephyrin (Geph) in the entopeduncular nucleus (EP) and globus pallidus (GP). A higher burst firing and a lower percentage of correlation between MSNs post-Saline firing rate vs. locomotion predicted the expression of locomotor sensitization. Moreover, during the AMPH challenge, we observed that burst firing decreased in sensitized rats, in contrast to non-sensitized rats in which burst firing was maintained. Finally, a higher Geph density on GP but not EP was observed in non-sensitized rats after AMPH challenge. These results indicate that initial differences in DLS burst firing might underlie the susceptibility to express locomotor sensitization and suggest that the potentiation of dorsal striatum indirect pathway could be considered a protective mechanism to locomotor sensitization.

[Antipsychotic-induced motor symptoms in schizophrenic psychoses-Part 1 : Dystonia, akathisia und parkinsonism]

Acute antipsychotic-induced movement disorders (AIMD) are clinically relevant since they are frequently associated with high subjective distress, and since over the long-term they can negatively impact treatment adherence of patients with schizophrenic psychoses. This review article summarizes the relevant studies on the prevalence, risk factors, prevention and treatment options and instruments for early prediction of acute AIMD in schizophrenic psychoses. The current evidence and treatment recommendations are divided into three main areas: acute dystonia, akathisia, and parkinsonism. For the treatment of acute dystonia trihexyphenidyl and biperiden have shown their efficacy. Considering pharmacological treatment of akathisia, there is some preliminary evidence for medication with lipophilic beta-receptor blockers (propranolol and pindolol), clonidine, benzodiazepines, mianserin, mirtazapine und trazodone. The treatment options for drug-induced parkinsonism include reduction or switching from one antipsychotic to another with a lower affinity for dopamine D₂ receptors, amantadine or in the regular administration of anticholinergic drugs. In conclusion, acute AIMD is easily to recognize but is not always effectively and durably treated. Early recognition and treatment of acute AIMD could be associated with improved treatment outcomes.

Unravelling subjectivity, embodied experience and (taking) psychotropic medication

This paper explores how distinctions between ‘intended’ and ‘side’ effects are troubled in personal narratives of taking psychotropic medications. Grounded in interviews with 29 participants diagnosed with mental illness in Victoria, Australia between February and December 2014, we consider how people interpret pharmaceutical compounds beyond their desired or intended effects, and how such effects shape and transform subjectivity and their relationship with their bodies. This paper contributes to recent discussions of mental illness and medication effects, informed by feminist science studies. It emphasises the co-constitution of social, affective and material relations in the context of ‘taking’ psychotropic medication. This paper discusses three key themes as important to the phenomenology of the nexus of illness and psychotropic medication: movement, ambivalence, and sociality. Our analysis demonstrates how psychotropic drugs are productive of subjectivity through their promises and potential, their unexpected harms and the institutions from which they are inseparable.

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Analyses accounts of mental illness using feminist science and technology studies.

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Focus on experiences of taking psychotropic drugs and impact on subjectivity.

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Moves beyond distinctions between ‘therapeutic’ and ‘side’ effects of drugs.

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Unique contribution to understandings of experiences of taking psychotropic drugs.

Akathisia Induced by Abrupt Withdrawal of Risperidone: A Case Report

Akathisia is a common movement disorder that occurs as a consequence of antipsychotic therapy. However, its occurrence secondary to risperidone withdrawal has been reported rarely. Reporting of such rare adverse event gains profound importance because changing the antipsychotics is very common in long term management of affective disorders. Here, we report a 17-year-old female who on withdrawal of risperidone developed akathisia. Further, we also discuss already reported cases in literature in relation to the current case.

Application of sedation-agitation scale in conscious sedation before bronchoscopy in children

This retrospective study investigated the application of the sedation-agitation scale (SAS) in pediatric bronchoscopy by observing its effects on sedative dosages and adverse reactions.Children who underwent sedation before bronchoscopy, during the period from January 2014 to June 2017, were divided into control and SAS groups. Patients in the control group were administered a single dose of 0.1 to 0.3 mg/kg midazolam, based on physicians' clinical experience. The initial dose of midazolam in the SAS group was 0.1 mg/kg, and was adjusted based on the SAS score, as evaluated by physicians. Between-group comparisons were made of midazolam dose; adverse reactions of midazolam, such as agitation, delirium, excessive sedation, and respiratory depression; operating time of bronchoscopy; and number of participants.No statistically significant differences in gender, age distribution, weight, or disease composition were observed between the groups. The midazolam dose, operating time, and number of participants at different ages were all lower in the SAS group than in the control group. Fewer adverse drug reactions, such as intraoperative agitation and delirium, were noted in the SAS group. Moreover, the overall number of participants was reduced, and the overall operating time was less than that in the control group.Application of SAS for assessment of sedation during pediatric bronchoscopy can guide individualized administration of midazolam, reduce midazolam dose while achieving an ideal sedative effect, reduce adverse reactions, and improve operator experience. Hence, its use should be promoted for pediatric patients undergoing bronchoscopy under local anesthesia and conscious sedation.

Antipsychotic-induced akathisia in delirium: A systematic review

OBJECTIVE

Akathisia is a neuropsychiatric syndrome characterized by subjective and objective restlessness. It is a common side effect in patients taking antipsychotics and other psychotropics. Patients with delirium are frequently treated with antipsychotic medications that are well known to induce akathisia as a side effect. However, the prevalence, phenomenology, and management of akathisia in patients with delirium remain largely unknown. The purpose of this review was to examine the medical literature in order to establish the current state of knowledge regarding the prevalence of antipsychotic-induced akathisia in patients with delirium.

METHOD

A systematic review of the literature was conducted using the EMBASE, MEDLINE, PsycINFO, and CINAHL databases. Ten studies addressing the incidence of akathisia in patients taking antipsychotic medication for delirium were identified and included in our review.

RESULTS

The included studies reported a variable prevalence of antipsychotic-induced akathisia. A higher prevalence was found in patients taking haloperidol. Among atypical antipsychotics, paliperidone and ziprasidone were associated with a higher risk of akathisia. The risk for akathisia appeared to be a dose-related phenomenon.

SIGNIFICANCE OF RESULTS

Studies using specific scales for evaluation of akathisia in delirium are lacking. Some populations, such as patients with cancer or terminally ill patients in palliative care settings taking antipsychotics for the treatment of delirium, could be at higher risk for development of akathisia as a side effect.

Fluphenazine versus low-potency first-generation antipsychotic drugs for schizophrenia

BACKGROUND

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between any other antipsychotic compounds, however, low-potency antipsychotic drugs are often perceived as less efficacious than high-potency compounds by clinicians, and they also seem to differ in their side effects. This review examined the effects of the high-potency antipsychotic fluphenazine compared to those of low-potency antipsychotics.

OBJECTIVES

To review the effects of fluphenazine and low-potency antipsychotics for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (November 2010).

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing fluphenazine with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model.

MAIN RESULTS

The review currently includes seven randomised trials and 1567 participants that compared fluphenazine with low-potency antipsychotic drugs. The size of the included studies was between 40 and 438 participants. Overall, sequence generation, allocation procedures and blinding were poorly reported. Fluphenazine was not significantly different from low-potency antipsychotic drugs in terms of response to treatment (fluphenazine 55%, low-potency drug 55%, 2 RCTs, n = 105, RR 1.06 CI 0.75 to 1.50, moderate quality evidence). There was also no significant difference in acceptability of treatment with equivocal numbers of participants leaving the studies early due to any reason (fluphenazine 36%, low-potency antipsychotics 36%, 6 RCTs, n = 1532, RR 1.00 CI 0.88 to 1.14, moderate quality evidence). There was no significant difference between fluphenazine and low-potency antipsychotics for numbers experiencing at least one adverse effect (fluphenazine 70%, low-potency antipsychotics 88%, 1 RCT, n = 65, RR 0.79 CI 0.58 to 1.07, moderate quality evidence). However, at least one movement disorder occurred significantly more frequently in the fluphenazine group (fluphenazine 15%, low-potency antipsychotics 10%, 3 RCTs, n = 971, RR 2.11 CI 1.41 to 3.15, low quality of evidence). In contrast, low-potency antipsychotics produced significantly more sedation (fluphenazine 20%, low-potency antipsychotics 64%, 1 RCT, n = 65, RR 0.31 CI 0.13 to 0.77, high quality evidence). No data were available for the outcomes of death and quality of life. The results of the primary outcome were robust in a number of subgroup and sensitivity analyses.Adverse effects such as akathisia (fluphenazine 15%, low-potency antipsychotics 6%, 5 RCTs, n = 1209, RR 2.28 CI 1.58 to 3.28); dystonia (fluphenazine 5%, low-potency antipsychotics 2%, 4 RCTs, n = 1309, RR 2.66 CI 1.25 to 5.64); loss of associated movement (fluphenazine 20%, low-potency antipsychotics 2%, 1 RCT, n = 338, RR 11.15 CI 3.95 to 31.47); rigor (fluphenazine 27%, low-potency antipsychotics 12%, 2 RCTs, n = 403, RR 2.18 CI 1.20 to 3.97); and tremor (fluphenazine 15%, low-potency antipsychotics 6%, 2 RCTs, n = 403, RR 2.53 CI 1.37 to 4.68) occurred significantly more frequently in the fluphenazine group.For other adverse effects such as dizziness (fluphenazine 8%, low-potency antipsychotics 17%, 4 RCTs, n = 1051, RR 0.49 CI 0.32 to 0.73); drowsiness (fluphenazine 18%, low-potency antipsychotics 25%, 3 RCTs, n = 986, RR 0.67 CI 0.53 to 0.86); dry mouth (fluphenazine 11%, low-potency antipsychotics 18%, 4 RCTs, n = 1051, RR 0.63 CI 0.45 to 0.89); nausea (fluphenazine 4%, low-potency antipsychotics 15%, 3 RCTs, n = 986, RR 0.25 CI 0.14 to 0.45); and vomiting (fluphenazine 3%, low-potency antipsychotics 8%, 3 RCTs, n = 986, RR 0.36 CI 0.18 to 0.72) results favoured fluphenazine with significantly more events occurring in the low-potency antipsychotic group for these outcomes.

AUTHORS' CONCLUSIONS

The results do not show a clear difference in efficacy between fluphenazine and low-potency antipsychotics. The number of included studies was low and their quality moderate. Therefore, further studies would be needed to draw firm conclusions about the relative effects of fluphenazine and low-potency antipsychotics.

Effectiveness of paliperidone palmitate vs haloperidol decanoate for maintenance treatment of schizophrenia: a randomized clinical trial

IMPORTANCE

Long-acting injectable antipsychotics are used to reduce medication nonadherence and relapse in schizophrenia-spectrum disorders. The relative effectiveness of long-acting injectable versions of second-generation and older antipsychotics has not been assessed.

OBJECTIVE

To compare the effectiveness of the second-generation long-acting injectable antipsychotic paliperidone palmitate with the older long-acting injectable antipsychotic haloperidol decanoate.

DESIGN, SETTING, AND PARTICIPANTS

Multisite, double-blind, randomized clinical trial conducted from March 2011 to July 2013 at 22 US clinical research sites. Randomized patients (n = 311) were adults diagnosed with schizophrenia or schizoaffective disorder who were clinically assessed to be at risk of relapse and likely to benefit from a long-acting injectable antipsychotic.

INTERVENTIONS

Intramuscular injections of haloperidol decanoate 25 to 200 mg or paliperidone palmitate 39 to 234 mg every month for as long as 24 months.

MAIN OUTCOME MEASURES

Efficacy failure, defined as a psychiatric hospitalization, a need for crisis stabilization, a substantial increase in frequency of outpatient visits, a clinician's decision that oral antipsychotic could not be discontinued within 8 weeks after starting the long-acting injectable antipsychotics, or a clinician's decision to discontinue the assigned long-acting injectable due to inadequate therapeutic benefit. Key secondary outcomes were common adverse effects of antipsychotic medications.

RESULTS

There was no statistically significant difference in the rate of efficacy failure for paliperidone palmitate compared with haloperidol decanoate (adjusted hazard ratio, 0.98; 95% CI, 0.65-1.47). The number of participants who experienced efficacy failure was 49 (33.8%) in the paliperidone palmitate group and 47 (32.4%) in the haloperidol decanoate group. On average, participants in the paliperidone palmitate group gained weight and those in the haloperidol decanoate group lost weight; after 6 months, the least-squares mean weight change for those taking paliperidone palmitate was increased by 2.17 kg (95% CI, 1.25-3.09) and was decreased for those taking haloperidol decanoate (-0.96 kg; 95% CI, -1.88 to -0.04). Patients taking paliperidone palmitate had significantly higher maximum mean levels of serum prolactin (men, 34.56 µg/L [95% CI, 29.75-39.37] vs 15.41 µg/L [95% CI, 10.73-20.08]; P <.001, and for women, 75.19 [95% CI, 63.03-87.36] vs 26.84 [95% CI, 13.29-40.40]; P<.001). Patients taking haloperidol decanoate had significantly larger increases in global ratings of akathisia (0.73 [95% CI, 0.59-0.87] vs 0.45 [95% CI, 0.31-0.59]; P=.006).

CONCLUSIONS AND RELEVANCE

In adults with schizophrenia or schizoaffective disorder, use of paliperidone palmitate vs haloperidol decanoate did not result in a statistically significant difference in efficacy failure, but was associated with more weight gain and greater increases in serum prolactin, whereas haloperidol decanoate was associated with more akathisia. However, the CIs do not rule out the possibility of a clinically meaningful advantage with paliperidone palmitate.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01136772.

Pericyazine for schizophrenia

BACKGROUND

Pericyazine is a 3-cyano-10 (3-4'-hydroxypiperidinopropyl) phenothiazine. It is overall pharmacologically similar with chlorpromazine, though particularly sedating. Dopamine receptor subtype analysis has not been performed for pericyazine, but the drug appears to induce greater noradrenergic than dopaminergic blockade. Compared to chlorpromazine, pericyazine reportedly has more potent antiemetic, antiserotonin, and anticholinergic activity.

OBJECTIVES

To evaluate the clinical effects and safety of pericyazine in comparison with placebo, typical and atypical antipsychotic agents and standard care for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (February 2013) which is based on regular searches of CINAHL, EMBASE, MEDLINE and PsycINFO. We inspected references of all identified studies for further trials.

SELECTION CRITERIA

All relevant randomised controlled trials focusing on pericyazine for schizophrenia and other types of schizophrenia-like psychoses (schizophreniform and schizoaffective disorders). We excluded quasi-randomised trials.

DATA COLLECTION AND ANALYSIS

Data were extracted independently from included papers by at least two review authors. Risk ratios (RR) and 95% confidence intervals (CI) of homogeneous dichotomous data were calculated. We assessed risk of bias for included studies and used GRADE to judge quality of evidence.

MAIN RESULTS

We could only include five studies conducted between 1965 and 1980. Most of the included studies did not report details of randomisation, allocation concealment, details of blinding and we could not assess the impact of attrition due to poor reporting.For the primary outcome of Global state - not improved, the confidence interval was compatible with a small benefit and increased risk of not improving with pericyazine compared with typical antipsychotics (2 RCTs, n = 122, RR 1.24 CI 0.93 to 1.66, very low quality of evidence) or atypical antipsychotics (1 RCT, n = 93, RR 0.97 CI 0.67 to 1.42, very low quality of evidence).When compared with typical antipsychotics relapse was only experienced by one person taking pericyazine (1 RCT, n = 80, RR 2.59 CI 0.11 to 61.75, very low quality of evidence).Pericyazine was associated with more extrapyramidal side effects than typical antipsychotics (3 RCTs, n = 163, RR 0.52 CI 0.34 to 0.80, very low quality of evidence) and atypical antipsychotics (1 RCT, n = 93, RR 2.69 CI 1.35 to 5.36, very low quality of evidence).The estimated risk of leaving the study early for specific reasons was imprecise for the comparisons of pericyazine with typical antipsychotics (2 RCTs, n = 71, RR 0.46 CI 0.11 to 1.90, very low quality of evidence), and with atypical antipsychotics (1 RCT, n = 93, RR 0.13 CI 0.01 to 2.42, very low quality of evidence).

AUTHORS' CONCLUSIONS

On the basis of very low quality evidence we are unable to determine the effects of pericyazine in comparison with typical or atypical antipsychotics for the treatment of schizophrenia. However, there is some evidence that pericyazine may be associated with a higher incidence of extrapyramidal side effects than other antipsychotics, and again this was judged to be very low quality evidence. Large, robust studies are still needed before any firm conclusions can be drawn.

PFOS induces behavioral alterations, including spontaneous hyperactivity that is corrected by dexamfetamine in zebrafish larvae

Perfluorooctane sulfonate (PFOS) is a widely spread environmental contaminant. It accumulates in the brain and has potential neurotoxic effects. The exposure to PFOS has been associated with higher impulsivity and increased ADHD prevalence. We investigated the effects of developmental exposure to PFOS in zebrafish larvae, focusing on the modulation of activity by the dopaminergic system. We exposed zebrafish embryos to 0.1 or 1 mg/L PFOS (0.186 or 1.858 µM, respectively) and assessed swimming activity at 6 dpf. We analyzed the structure of spontaneous activity, the hyperactivity and the habituation during a brief dark period (visual motor response), and the vibrational startle response. The findings in zebrafish larvae were compared with historical data from 3 months old male mice exposed to 0.3 or 3 mg/kg/day PFOS throughout gestation. Finally, we investigated the effects of dexamfetamine on the alterations in spontaneous activity and startle response in zebrafish larvae. We found that zebrafish larvae exposed to 0.1 mg/L PFOS habituate faster than controls during a dark pulse, while the larvae exposed to 1 mg/L PFOS display a disorganized pattern of spontaneous activity and persistent hyperactivity. Similarly, mice exposed to 0.3 mg/kg/day PFOS habituated faster than controls to a new environment, while mice exposed to 3 mg/kg/day PFOS displayed more intense and disorganized spontaneous activity. Dexamfetamine partly corrected the hyperactive phenotype in zebrafish larvae. In conclusion, developmental exposure to PFOS in zebrafish induces spontaneous hyperactivity mediated by a dopaminergic deficit, which can be partially reversed by dexamfetamine in zebrafish larvae.

Second-generation antipsychotic drugs and extrapyramidal side effects: a systematic review and meta-analysis of head-to-head comparisons

OBJECTIVE

While all second-generation antipsychotics (SGAs) are promoted for having a low risk of extrapyramidal side effects (EPS), clinical observations suggest differences between the various agents. Nevertheless, this question has never been examined in a systematic review and meta-analysis of head-to-head comparisons.

METHODS

We searched the register of the Cochrane schizophrenia group (last search May 2007), supplemented by MEDLINE (last search July 2009) for randomized, blinded studies comparing the following SGAs in the treatment of schizophrenia or related disorders: amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone, and zotepine. At least 3 reviewers extracted the data independently. The primary outcome was "use of antiparkinson medication." The results were combined in a meta-analysis.

RESULTS

We included 54 studies with 116 arms. Risperidone was associated with more use of antiparkinson medication than clozapine, olanzapine, quetiapine, and ziprasidone. Ziprasidone showed more use of antiparkinson medication than olanzapine and quetiapine and zotepine more than clozapine. There was no significant difference between amisulpride and its comparators (olanzapine, risperidone, or ziprasidone). Quetiapine showed significantly less use of antiparkinson medication than the 3 other SGAs it was compared with (olanzapine, risperidone, and ziprasidone). Scale-derived data (Barnes Akathisia Scale and Simpson Angus Scale) were limited.

CONCLUSIONS

Our meta-analysis demonstrates that there are differences between the SGAs in their ability to induce EPS that clinicians consider warrant treatment with antimuscarinic drugs. Even though the differences were relatively small, they might be important for individual patients and should be taken into account in drug choice.

Risperidone-to-methylphenidate switch reaction in children: three cases

As atypical antipsychotics are increasingly used in the treatment of childhood behavioural disorders either as monotherapy or in combination with other medications, there is a need to know more about their safety, in particular during switching to and from methylphenidate treatment, as antipsychotics and methylphenidate have opposing effects on dopaminergic neurotransmission. This report is about three cases of children who developed severe adverse reactions during switching from risperidone to methylphenidate. The first patient was a 6-year-old boy, diagnosed with attention deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD). He developed severe hyperactivity and agitation on taking methylphenidate after the discontinuation of risperidone treatment. The second patient was a girl of 6, already on risperidone for ADHD and borderline intellectual functioning when referred. She displayed severe hyperactivity, agitation and irritability upon switching to methylphenidate medication. The third patient was a 15-year-old female adolescent with a similar clinical course as the previous patients. In all the cases described here, it is only with the discontinuation of methylphenidate that the adverse reactions resolved and readministration of methylphenidate in two patients did not produce any adverse effect after a drug-free interval. Functional regulation of certain neuroreceptors during risperidone treatment may lead to altered behavioural responses upon switching to methylphenidate. Thus, a drug-free interval is recommended in order to prevent adverse reactions.

S-Allylcysteine prevents the rat from 3-nitropropionic acid-induced hyperactivity, early markers of oxidative stress and mitochondrial dysfunction

We investigated the effects of S-allylcysteine (SAC) on early behavioral alterations, striatal changes in superoxide dismutase (SOD) activity, lipid peroxidation (LP) and mitochondrial dysfunction induced by the systemic infusion of 3-nitropropionic acid (3-NPA) to rats. SAC (300 mg/kg, i.p.), given to animals 30 min before 3-NPA (30 mg/kg, i.p.), prevented the hyperkinetic pattern evoked by the toxin. In addition, 3-NPA alone produced decreased activities of manganese- (Mn-SOD) and copper/zinc-dependent superoxide dismutase (Cu,Zn-SOD), increased LP (evaluated as the formation of lipid fluorescent products) and produced mitochondrial dysfunction in the striatum (measured as decreased 3-(3,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction). In contrast, pretreatment of 3-NPA-injected rats with SAC resulted in a significant prevention of all these markers. Our findings suggest that the protective actions of SAC are related with its antioxidant properties, which in turn may be accounting for the preservation of SOD activity and primary mitochondrial tasks.

[Suicidal ideations and suicide attempts after starting on aripiprazole, a new antipsychotic drug]

In 5 patients, 3 women aged 30, 32 and 41 years and 2 men aged 36 and 56 years, serious side effects developed after starting aripiprazole, a new antipsychotic drug. 2 patients had not been treated with antipsychotic drugs before, while in 3 there was a switch in antipsychotic treatment. The side effects consisted primarily oftroubling feelings ofagitation, akathisia, insomnia and dysphoria. 3 of the patients made a suicide attempt and 2 developed suicidal thoughts. The patients had not previously attempted suicide and the suicidal thoughts disappeared after discontinuation ofaripiprazole. Suicidal tendencies have not been reported before as a side effect ofaripiprazole.

Effectiveness and cost of olanzapine and haloperidol in the treatment of schizophrenia: a randomized controlled trial

CONTEXT

Although olanzapine has been widely adopted as a treatment of choice for schizophrenia, its long-term effectiveness and costs have not been evaluated in a controlled trial in comparison with a standard antipsychotic drug.

OBJECTIVE

To evaluate the effectiveness and cost impact of olanzapine compared with haloperidol in the treatment of schizophrenia.

DESIGN AND SETTING

Double-blind, randomized controlled trial with randomization conducted between June 1998 and June 2000 at 17 US Department of Veterans Affairs medical centers.

PARTICIPANTS

Three hundred nine patients with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of schizophrenia or schizoaffective disorder, serious symptoms, and serious dysfunction for the previous 2 years. Fifty-nine percent fully completed and 36% partially completed follow-up assessments.

INTERVENTIONS

Patients were randomly assigned to receive flexibly dosed olanzapine, 5 to 20 mg/d, with prophylactic benztropine, 1 to 4 mg/d (n = 159); or haloperidol, 5 to 20 mg/d (n = 150), for 12 months.

MAIN OUTCOME MEASURES

Standardized measures of symptoms, quality of life, neurocognitive status, and adverse effects of medication. Veterans Affairs administrative data and interviews concerning non-VA service use were used to estimate costs from the perspective of the VA health care system and society as a whole (ie, consumption of all resources on behalf of these patients).

RESULTS

There were no significant differences between groups in study retention; positive, negative, or total symptoms of schizophrenia; quality of life; or extrapyramidal symptoms. Olanzapine was associated with reduced akathisia in the intention-to-treat analysis (P<.001) and with lower symptoms of tardive dyskinesia in a secondary analysis including only observations during blinded treatment with study drug. Small but significant advantages were also observed on measures of memory and motor function. Olanzapine was also associated with more frequent reports of weight gain and significantly greater VA costs, ranging from 3000 dollars to 9000 dollars annually. Differences in societal costs were somewhat smaller and were not significant.

CONCLUSION

Olanzapine does not demonstrate advantages compared with haloperidol (in combination with prophylactic benztropine) in compliance, symptoms, extrapyramidal symptoms, or overall quality of life, and its benefits in reducing akathisia and improving cognition must be balanced with the problems of weight gain and higher cost.

[Effect of propofol on sevoflurane agitation in children]

BACKGROUND

Sevoflurane may be associated with a high incidence of agitation during recovery from anesthesia in children. We tested the hypothesis that bolus administration of propofol after sevoflurane anesthesia would reduce the incidence of recovery agitation compared with sevoflurane anesthesia alone.

METHODS

We conducted a randomized, double-blinded study in 90 children, 1-7 yr of age, undergoing short general anesthesia. They were divided into three groups; 2 mg.kg-1 propofol (group P2), 1 mg.kg-1 propofol (group P1) and intralipid 0.2 ml.kg-1 as control (group C). After sevoflurane induction and maintenance and 5 minutes before the end of operation, propofol or intralipid was administered. We compared the speed and quality of each recovery. We made a new scoring system for the assessment of agitation. Each child received a point from -4 to 10 with this system.

RESULTS

Recovery score was similar among the three groups (group P2 had point 4, group P1, point 5, and group C point 4). Recovery time in group P2 was significantly longer than that in group C (about 6 minutes).

CONCLUSIONS

Bolus administration of propofol after sevoflurane anesthesia prolonged recovery time, but did not inhibit sevoflurane agitation compared with sevoflurane anesthesia alone.

Atypical antipsychotics: experience and use in the elderly

The use of antipsychotics is common in the elderly Typical antipsychotics are not without risk, especially in tardive dyskinesia, which, when balanced against relatively low efficacy, make their use debatable. Atypical antipsychotics have much less in the way of side-effects and are much less likely to induce tardive dyskinesia. However, there is much less in the published literature about the efficacy of these drugs in the elderly and how best to use them in primary psychosis, Parkinson's disease and the behavioural and psychological symptoms of dementia. This review attempts to summarise the current literature and make some tentative recommendations for each of the commonest atypicals, based on the current evidence.

The bioavailability and pharmacokinetics of subcutaneous, nebulized and oral morphine-6-glucuronide

AIMS

Morphine-6-glucuronide (M6G), one of the active metabolites of morphine, has attracted considerable interest as a potent opioid analgesic with an apparently superior therapeutic index. To date studies have used the intravenous route, which is generally unacceptable in the treatment of cancer related pain. The aim of this study was to define the pharmacokinetics, toxicity and cardio-respiratory effects of three alternative routes of administration of M6G.

METHODS

Ten healthy volunteers participated in an open randomized study. Subjects received M6G 2 mg as an intravenous bolus, 20 mg orally, 2 mg subcutaneously and 4 mg by the nebulized route. Pulse, blood pressure, respiratory rate and peak flow rate were monitored and subjective toxicity recorded on rating and visual analogue scales.

RESULTS

After i.v. M6G the mean (+/- s.d.) AUC(0,infinity) standardized to a dose of 1 mg was 223 +/- 57 nmol l(-1) h, mean elimination half-life was 1.7 +/- 0.7 h and the mean clearance was 157 +/- 46 ml min(-1). These parameters were virtually identical after subcutaneous administration which had a bioavailability (F(0,infinity)) of 102 +/- 35% (90% CI 82, 117%) and t(max) of 0.5 +/- 0.2 h. The mean bioavailability of nebulized M6G was 6 +/- 2% (90% CI 4, 7%) with a t(max) of 1.2 +/- 0.8 h. Following oral M6G two plasma M6G peaks were seen in 7 of the 10 subjects, the first with a t(max) of 3.1 (+/- 0.9) h. The second peak had a t(max) of 13.4 (+/-5.0) h, started approximately 4 h after dosing, and was associated with the detection of plasma M3G and morphine, suggesting that M6G was significantly hydrolysed in the gut to morphine, which was then glucuronidated following absorption. Although the overall mean bioavailability was 11 +/- 3% (90% CI 9, 12%), confining the analysis to data from the first peak suggested a bioavailability of directly absorbed M6G of only 4 +/- 4%. Apart from a characteristic dysphoria following intravenous and subcutaneous M6G, there was no significant toxicity.

CONCLUSIONS

With the minimal toxicity reported in this and previous studies, subcutaneous infusion of M6G may potentially provide clinically useful analgesia for advanced cancer pain. Nebulized M6G is not significantly absorbed via the lungs, and if opiates are shown to have a local effect in the lung, reducing the sensation of breathlessness, then nebulized administration is likely to minimize systemic effects. Oral M6G has poor bioavailability, but is significantly hydrolysed in the gut to morphine, which is subsequently glucuronidated following absorption. This circuitous route accounts for the majority of systemically available M6G after oral administration.

Restlessness in suboccipital muscles as a manifestation of akathisia

Antipsychotic-induced akathisia is primarily manifested as restlessness, particularly expressed in the legs. Consequently, rating scales and the research criteria of DSM-IV regard restlessness in the legs as the major sign of akathisia, although it has been suggested that such restlessness may occur in other areas of the body. A case of antipsychotic-induced akathisia is reported where the region of inner restlessness (the subjective component) was identified in posterior cervical muscles. The patient was initially suspected to be experiencing somatic delusions and the dose of antipsychotic medication was increased. This did not improve the symptoms, and upon careful questioning about his head discomfort, the patient acknowledged that he felt an inner restlessness in the suboccipital muscles. The restlessness ceased with intramuscular biperiden and subsequent discontinuation of antipsychotic medication. This case suggests that subjective restlessness may occur in muscle groups that are not usually associated with akathisia. Thus, this report may assist clinicians in the diagnosis of akathisia that could be overlooked or misdiagnosed as somatic delusions or the worsening of the patient's psychosis.

Clomipramine augmentation in treatment-resistant depression

In depression that is resistant to tricyclic antidepressant (TCA) therapy, the substitution of a selective serotonin re-uptake inhibitor (SSRI), clomipramine, or a monoamine oxidase (MAO) inhibitor has been recommended. However, adding an additional antidepressant medication from a different drug class may produce even more rapid efficacy. In this regard, the combination of a MAO inhibitor or a SSRI plus a TCA has been shown to be of value in treatment-resistant depression (TRD). In this report, we examined the efficacy of clomipramine augmentation in 20 patients who failed to respond to either a MAO inhibitor or fluoxetine therapy for at least a 6-week period, and compared this to a third group given MAO inhibitor plus a conventional TCA. Two out of 9 (22%) MAO inhibitor/clomipramine patients and 4 out of 11 (36%) fluoxetine/clomipramine patients improved (Fisher's Exact test, P = ns), compared to 3 out of 7 (43%) patients taking MAO inhibitor/TCA (P = ns). However, the MAO inhibitor/clomipramine group experienced significantly more adverse events which necessitated stopping treatment (56%) when compared to the fluoxetine/clomipramine (9%) and compared to the MAO inhibitor/TCA group (0%) (chi 2 = 8.9, df = 2, P < 0.05). These adverse events included several cases of serotonin syndrome of mild to moderate severity. These observations indicate that clomipramine augmentation of a failed MAO inhibitor trial is of marginal efficacy (compared to augmentation with a conventional TCA) and should be employed with extreme caution.

Fluoxetine and concomitant centrally acting medication use during clinical trials of depression: the absence of an effect related to agitation and suicidal behavior

Concomitant use of psychoactive medications is a common practice in most clinical trials of antidepressant medications. However, the relative therapeutic impact of such use on trial results has not been the subject of much attention. We conducted a meta-analysis to determine whether concomitant use of psychoactive medications confounded the efficacy or safety results of a series of fluoxetine trials. Data were evaluated from 25 randomized, double-blind clinical trials comparing fluoxetine with placebo or a tricyclic antidepressant (TCA) in 4,016 patients with major depression. We compared incidence rates of concomitant use of anxiolytics, sedatives, and antipsychotics between treatments. In addition, we compared the change in total score for the 21-Item Hamilton Depression Rating Scale (HAMD21): incidence rates of any worsening, emergence, or improvement in psychomotor agitation; and incidence of suicidal acts and any worsening, emergence, or improvement in suicidal ideation between treatment groups among patients taking/not taking a sedative. Anxiolytic and antipsychotic drug use was uncommon (8.3% and 0.9% overall use, respectively) and did not substantially increase over time. Sedative drugs were used most often (29.6% overall), but only 29.8% of the fluoxetine-treated patients took one or more doses. Regarding efficacy, fluoxetine was superior to placebo in decreasing HAMD21 total scores among patients taking/not taking sedatives. Effects on safety were assessed by examining agitation and suicidal ideation. Use of sedatives did not affect the change in the HAMD agitation score; scores were similar in patients receiving fluoxetine, placebo, and TCAs. In all treatment groups, anxiolytic use tended to increase as the HAMD anxiety score increased. Fluoxetine was superior to placebo in treating suicidal ideation, and the concomitant use of sedatives did not influence this effect. Overall, concomitant use of psychotropic medications in the fluoxetine depression clinical trials was uncommon. Our meta-analysis demonstrated that the clinical efficacy and safety of fluoxetine were not confounded by the concomitant use of medications.

New antipsychotic medications: more than old wine and new bottles

Four new antipsychotic medications--clozapine, risperidone, olanzapine, and quetiapine--have been introduced in the United States during the past decade. These new medications now account for the majority of antipsychotic prescriptions. The author reviews specific issues related to the use of traditional antipsychotic medications and then highlights the emerging clinical research data regarding the new medications, which have all been shown to be efficacious in the treatment of schizophrenia. Clinical research data indicate that they are also more useful for a broader array of symptoms associated with schizophrenia than traditional compounds. Furthermore, movement disorder side effects are substantially decreased--a property that leads to higher acceptability. Surprisingly, there has been little relationship between the pivotal trials designed for FDA approval and current dosing strategies in broader clinical settings. These dosing issues are described. New uses, including treatment of mood disorders and conduct disorder, are also discussed. These medicines offer substantial hope for improved treatment of schizophrenia.

Comparative efficacy of olanzapine and haloperidol for patients with treatment-resistant schizophrenia

BACKGROUND

There is relatively little information regarding the efficacy of newer atypical antipsychotic drugs for patients with schizophrenia who are treatment-resistant to neuroleptic agents. Several lines of evidence suggest that a clinical trial of olanzapine in this population is warranted.

METHODS

A subpopulation of patients (n = 526) meeting treatment-resistant criteria selected from a large, prospective, double-blind, 6-week study assessing the efficacy and safety of olanzapine and haloperidol were examined. Both last-observation-carried-forward (LOCF) and completers (observed cases) analyses were conducted.

RESULTS

Olanzapine demonstrated significantly greater mean improvement from baseline in Positive and Negative Syndrome Scale (PANSS) negative symptoms, comorbid depressive symptoms assessed by the Montgomery-Asberg Depression Rating Scale, akathisia as measured by Barnes Akathisia Scale, and extrapyramidal symptoms as measured by Simpson-Angus Extrapyramidal Rating Scale with both LOCF and completers analyses. In addition, olanzapine was significantly superior to haloperidol for Brief Psychiatric Rating Scale total (p = .006), PANSS total (p = .005), and PANSS positive symptoms (p = .017) in completers of the 6-week study. Significantly greater response rates were observed in olanzapine-treated (47%) than haloperidol-treated (35%) patients in the LOCF analysis (p = .008), but significance was not reached in the completers analysis (p = .093). Mean doses (+/- SD) of olanzapine and haloperidol were 11.1 +/- 3.4 mg/day and 10.0 +/- 3.6 mg/day, respectively.

CONCLUSIONS

Olanzapine was superior to haloperidol for key symptom domains and parkinsonian side effects. Implications of these data for the therapeutics of this severely ill subgroup are discussed.

[Recent progress in akathisia]

Neuroleptic-induced akathisia should be definitely diagnosed as acute, tardive, withdrawal, and chronic. The diagnostic assessment must be identified from the subjective report and objective features. Various assessments of measuring akathisia can be clinically used by instrumental methods and rating scales. The pharmacological basis of neuroleptic-induced akathisia is the inhibition of the dopamine receptors in the brain. The pathogenesis of neuroleptic-induced akathisia may involve GABAergic hypoactivity, noradrenergic hyperactivity, and serotonergic dysfunction in CNS. Iron deficiency and hyperglycemia may be risk factors of neuroleptic induced akathisia in relation to the dopamine function in the brain. Neurological disorders may be associated with the development of a syndrome resembling drug-induced akathisia. The lesion of the thalamic nuclei would originally produce the syndrome. The difference between acute and tardive akathisia on the strategy of the drug treatment should be sufficiently comprehended. In particular, the long-term use of anticholinergic drugs and benzodiazepines should not be prevailed.

Effects of dopaminergic combination therapy for frontal lobe dysfunction in traumatic brain injury rehabilitation

Traumatic brain injury poses significant and diverse challenges to rehabilitation efforts. Neurobehavioural deficits represent a particularly difficult barrier to rehabilitative progress and societal reintegration. Early studies have identified dopaminergic drugs such as amantadine, bromocriptine and sinemet as potentially assistive in countering these deficits. To date, side effect profiles have been relatively benign, noted most frequently in small-scale case trials. The case of a 40-year-old patient with bilateral frontal traumatic brain injuries, and previous arteriovenous malformation (AVM) bleed with significant ataxia, dysarthria and neurobehavioural deficits is presented. This long range study demonstrates, through multiple varied dosing schedules, a trade off between the benefits and side effects of dopaminergic therapy, with implications for a larger brain injury population.

Tardive blepharospasm

I report on five patients with tardive blepharospasm seen in a movement disorders clinic, out of 25 tardive dystonia patients. They were young (aged 25-50 yrs); four were men and three had a schizophrenic disorder. The onset was gradual while on maintenance neuroleptics in four and on withdrawal in the fifth. There were no significant antecedent events precipitating the disorder. The disorder was bilateral but asymmetric in two cases. Dyskinetic blinking was often an initial feature and tended to persist after the resolution of the blepharospasm. Orolingual dyskinesia was present in one case and tardive akathisia in two other cases. The symptoms fluctuated in severity with a number of exacerbating and relieving factors. Reduction of neuroleptic dose led to improvement with complete reversal in one of two patients who could be withdrawn off neuroleptic medication. These reports suggest that TB, although uncommon, can be a disabling disorder that may improve considerably with the cessation or dose reduction of the neuroleptic drugs. Its treatment and longitudinal course should be further examined.

Side reaction caused by the perfluorocarbon emulsions in intravenous infusion to experimental animals

The perfluorocarbon (PFC) emulsions are infusion gas-transporting media and are usually called the artificial blood. However anaphylactoid reaction were observed during intravenous infusion of PFC emulsions. The cause of side reactions is the activation of the complement system. An indirect sign of the intravascular activation of the complement is the neutropenic effect in the peripheric blood. Taking into consideration the phenomen, the method of evaluation of anaphylactoid reaction caused by PFC emulsions has been elaborated using the neutropenic index. We evaluated the biocompatibility of 26 PFC emulsions of different composition in intravenous infusion to rabbits using this index. Emulsions evoked reactions of different extent. Some emulsions did not cause the neutropenic effect at all. Results of this work allow to reach conclusion, that influence of PFC emulsions on the complement system is explained not only by emulsifying agent proxanol: the stability of emulsions in the vascular bed and in the period of storage in frozen state is of great importance as well.

Effect of single doses of S-salbutamol, R-salbutamol, racemic salbutamol, and placebo on the airway response to methacholine

BACKGROUND

Commercially available salbutamol is a racemic mixture consisting of equal amounts of the two enantiomers, R-salbutamol and S-salbutamol, felt to be active and inert, respectively.

METHODS

A double blind, randomised, four way, crossover study was performed in 12 well controlled asthmatic subjects (forced expiratory volume in one second (FEV1) > 70% predicted, no beta 2 agonists for > or = 4 weeks). Subjects were studied on four days at intervals of 48 hours to seven days. FEV1 was assessed before and both FEV1 and methacholine PC20 were measured 20 and 180 minutes after a single dose of nebulised racemic salbutamol 2.5 mg, R-salbutamol 1.25 mg, S-salbutamol 1.25 mg, and placebo.

RESULTS

Equivalent bronchodilation was seen for both R-salbutamol and racemic salbutamol (mean (SE) 12.4 (3.1)% and 12.0 (3.0)%, respectively, at 20 minutes and 5.9 (2.9)% and 5.2 (2.2)% at 180 minutes). The increase in FEV1 of 5.2 (0.9)% at 20 minutes and the decline in FEV1 of 2.9 (2.1)% at 180 minutes after S-salbutamol were not significantly different from the placebo response. Compared with placebo the methacholine PC20 after R-salbutamol and racemic salbutamol improved by 3.3 (95% CI 2.5 to 4.1) and 3.4 (95% CI 2.6 to 4.2) doubling doses, respectively, at 20 minutes and 1.2 (95% CI 0.6 to 1.8) and 1.0 (95% CI 0.2 to 1.8) doubling doses at 180 minutes. S-salbutamol resulted in an improvement of 0.9 (95% CI 0.3 to 1.5) doubling doses at 20 minutes and no change at 180 minutes. Restlessness (n = 11) and increased pulse were seen 20 minutes after racemic and R-salbutamol but not S-salbutamol or placebo, and not at 180 minutes. There were no other adverse events.

CONCLUSION

A single dose of 1.25 mg nebulised R-salbutamol produced equivalent bronchoprotection, bronchodilation, restlessness, and tachycardia as did 2.5 mg of racemic salbutamol. S-salbutamol 1.25 mg had a weak bronchoprotective effect; this could be because of a small amount of contamination with R-salbutamol or because S-salbutamol is an intrinsically weak beta 2 receptor stimulant.

[Four-week intravenous toxicity study of montirelin hydrate (NS-3) in dogs followed by 4-week recovery test]

A repeated dose toxicity study of montirelin hydrate (NS-3), a new drug for the treatment of disturbance of consciousness, was conducted in beagle dogs. The dogs were given the drug intravenously for 4 weeks at doses of 0 (control), 0.0002, 0.002, 0.02, 0.2, 2 and 20 mg/kg in males and 0, 0.2, 2 and 20 mg/kg in females. After discontinuation of the treatment, a 4-week recovery test was also conducted in the 0 and 20 mg/kg groups. No deaths related to the treatment were observed. There were no changes in body weight gain, and food and water consumptions. Nasal discharge was seen in all dose groups. Salivation, emesis and hypoactivity were observed in the 0.2 mg/kg group and over. Licking chops were seen in the 2 and 20 mg/kg groups. Trembling and agitated/restless behavior were seen in the 20 mg/kg group. Electrocardiographic examination revealed elevated heart rate in the 0.2 mg/kg group and over. Ophthalmoscopic and hematologic examinations, and urinalysis failed to show any abnormalities attributable to the treatment. Blood chemical examination disclosed increases in T3 level in the 2 and 20 mg/kg groups of males and in T4 level in the 0.2 mg/kg group and over of males. There were no pathological findings attributable to the treatment. The changes mentioned above were satisfactorily reversible. The nasal discharge seen in the 0.02 mg/kg group and below was considered to be of no toxicological significance. These results show that the NOAEL of montirelin hydrate is 0.02 mg/kg for 4-week repeated dose toxicity in dogs.

Intrathecal prostaglandin E1 produces a long-lasting allodynic state

The existence of prostaglandin (PG) receptors in the spinal cord has been demonstrated, but their role in sensory processing is not yet well defined. PGE1 is widely used clinically as a vasodilator. The present study was designed to investigate the effects of intrathecally administered PGE1 on the transmission of different types to sensory information, including that associated with noxious somatic, noxious visceral, and non-noxious somatic stimulation. The tail-flick (TF) test was employed to measure responses to noxious somatic stimuli, and the colorectal distension test was used to examine responses to noxious visceral stimuli. Withdrawal response to mechanical pressure produced by Semmes-Weinstein mono-filaments (SWMs) was measured as an assessment of sensitivity to non-noxious mechanical somatic stimulation. TF latencies and colorectal distension thresholds decreased for a short time (10-20 min) following the intrathecal (i.t.) administration of both 100 ng or 500 ng of PGE1. In sharp contrast to these short duration effects, there was a long-lasting increase in agitation scores (allodynia) produced by 3 different intensities of SWMs (0.217, 0.745 and 2.35 g) after administration of PGE1. The changes in agitation scores to SWMs were dependent on the dose of PGE1 and the intensity of stimulation. This increase of agitation score was seen when PGE1 was administered through the i.t. catheter or by direct i.t. puncture and the increase lasted for at least 2 days after drug administration. Intrathecal administration of saline, however, did not produce any changes in TF latencies, colorectal distension thresholds, or agitation scores produced by SWMs. No significant histological difference was seen between spinal cords exposed to 500 ng PGE1 and saline 48 h after drug administration. These results demonstrate that PGE1 may trigger a hypersensitive (allodynic and/or hyperalgesic) state in sensory processing pathways at the spinal level. They also indicate that long-lasting changes in processing of non-noxious, but not noxious, information produced by PGE1 continues after the disappearance of the direct action of PGE1.

[Problems of epidural droperidol administration]

We describe three cases of extrapyramidal reactions apparently caused by epidural administration of droperidol. These patients suffered from chronic pain and was treated with epidural lidocaine and droperidol. Two patients received continuous administration of droperidol, and experienced acute dystonia and another after a single dose, developed akathisia. Adverse reactions occurred at 15, 20 and 24 hours after the administration of droperidol. The first patient received droperidol 6 mg, the second 8.5 mg and the third 5 mg. We consider that extrapyramidal reactions are due to overdoses because the patients who had been given less than 2.5 mg of droperidol a day, showed no adverse reaction. Although we use higher doses with NLA or for management of fever than with epidural administration of droperidol, we seldom encounter cases of side effects with droperidol. Epidurally administrated droperidol spreads rostral within the neuraxis and causes delayed extrapyramidal reactions as epidural morphine develops delayed respiratory depression. We must be careful in caring patients suffering from chronic pain with continuous epidural administration of droperidol.

Adverse effects of antipsychotic drugs

Since the introduction of chlorpromazine in the 1950s, neuroleptic medications have been the mainstay of treatment of schizophrenia and other psychotic disorders. These medications do not always lead to complete remission of symptoms but they have allowed many patients to lead more productive and satisfying lives away from the restrictions of chronic hospitalisation. However, neuroleptics are associated with a number of adverse effects that can compromise their effectiveness. Extrapyramidal adverse effects include acute dystonic reactions, neuroleptic-induced Parkinsonism and akathisia. They can often be treated with neuroleptic dose reduction, addition of anticholinergic or beta-blocking agents, or medication change. Later-onset movement disorders such as tardive dyskinesia or dystonia require careful evaluation and may be treated with dose reduction or change of neuroleptic to an atypical agent. Potentially fatal reactions such as agranulocytosis and neuroleptic malignant syndrome can rarely occur and often require significant medical intervention. Clozapine offers some advantages over 'typical' neuroleptics but has a unique adverse effect profile which includes agranulocytosis.

Effects of prior cocaine exposure on subsequent neuronal responsiveness

In vivo electrophysiological experiments were conducted to examine the responses of single, spontaneously-active neostriatal neurons to repeated cocaine exposure. The second of two administrations in a 30 min interval, attenuated the magnitude and duration of cocaine-induced depression in discharge rate, and enhanced the same variables for cocaine-evoked excitation. These findings indicate that the responsiveness of striatal neurons to cocaine may vary predictably as a function of previous exposure.

Cigarette smoking in schizophrenia: relationship to psychopathology and medication side effects

OBJECTIVE

The authors' goal was to study the relationship between smoking status and clinical characteristics in schizophrenic patients.

METHOD

Seventy-eight schizophrenic outpatients were assessed by a single rater using the Brief Psychiatric Rating Scale (BPRS), the Abnormal Involuntary Movement Scale, and the Simpson-Angus Scale for extrapyramidal symptoms. Current smokers (N = 58) were compared with nonsmokers (N = 20) on clinical variables by independent t tests and chi-square tests. Differences in outcome variables were tested by multiple analysis of covariance (ANCOVA) with smoking status and gender as factors and age, neuroleptic dose, and caffeine consumption as covariates.

RESULTS

Seventy-four percent of patients were current smokers and reported a mean of 19 cigarettes smoked per day. Compared to nonsmokers, current smokers were significantly more likely to be men, to be younger, and to have had an earlier age at onset and a greater number of previous hospitalizations. Current smokers and nonsmokers received mean neuroleptic doses of 1160 and 542 mg/day (chlorpromazine equivalents); the difference was significant. Current smokers also displayed significantly less parkinsonism and more akathisia and had higher total scores on the BPRS. Overall multiple ANCOVA demonstrated a significant main effect for smoking status but not gender or the interaction between gender and smoking status. Univariate ANCOVAs demonstrated a significant main effect of smoking status only for the Simpson-Angus Scale score.

CONCLUSIONS

Cigarette smokers receive significantly higher neuroleptic doses, in part because of a smoking-induced increase in neuroleptic metabolism. Smoking is also associated with significant reduction in levels of parkinsonism. Smoking status is a significant factor that should be considered in assessment of neuroleptic dose requirements and neuroleptic side effects.