Piracetam in the treatment of schizophrenia: implications for the glutamate hypothesis of schizophrenia

OBJECTIVE: There is a growing interest in investigating the role of glutamate receptors in the pathophysiology of schizophrenia. Indeed, the hyperdopaminergic theory of schizophrenia can explain only the positive symptoms of schizophrenia, whereas the glutamate hypothesis may provide a more comprehensive view of the illness. We undertook a trial to investigate whether the combination of haloperidol with piracetam, a nootropic agent which modulates the glutamate receptor positively was more effective than haloperidol alone. METHODS: Thirty patients who met the DSM IV criteria for schizophrenia completed the study. Patients were allocated in a random fashion, 14 to haloperidol 30 mg/day plus piracetam 3200 mg/day and 16 to haloperidol 30 mg/day plus placebo. RESULTS: Although both protocols significantly decreased the score of the positive symptoms, the negative symptoms, the general psychopathological symptoms and the total score of PANSS scale over the trial period, the combination of haloperidol and piracetam showed a significant superiority over haloperidol alone in the treatment of schizophrenic patients. CONCLUSION: Piracetam, a member of the nootropic class of drugs and a positive modulator of glutamate receptor, may be of therapeutic benefit in treating schizophrenic patients in combination with typical neuroleptics. However, a larger study to confirm our results is warranted     

Cyproheptadine in treatment of chronic schizophrenia:a double-blind, placebo-controlled study

OBJECTIVE: There is growing interest in investigating the role of 5-HT receptors in the physiopathology of schizophrenia in particular the negative symptoms. Indeed, newer atypical antipsychotics which interact with 5-HT receptors are more effective in the treatment of negative symptoms compared to typical neuroleptics. We undertook a trial to investigate whether the combination of haloperidol with cyproheptadine, a relatively safe serotonin-blocking agent was more effective than haloperidol alone. METHODS: Thirty patients who met the DSM IV criteria for chronic schizophrenia completed the study. Patients were allocated in a random fashion, 15 each to haloperidol 30 mg/day plus cyproheptadine 24 mg/ day and haloperidol 30 mg/day plus placebo. RESULTS: Although both protocols significantly decreased the positive and negative symptom score over the trial period, the combination of haloperidol and cyproheptadine showed significant superiority over haloperidol alone in the treatment of the negative symptoms. CONCLUSION: Cyproheptadine is a relatively safe compound and may be of therapeutic benefit in treating negative symptoms of schizophrenia in combination with typical neuroleptics. However, a larger study to confirm our results is warranted.     

Diazoxide in the treatment of schizophrenia: novel application of potassium channel openers in the treatment of schizophrenia

OBJECTIVE: Schizophrenia is a very common disorder, affecting 1% of the world population. People who develop schizophrenia experience severe suffering and approximately 10% commit suicide. The causes of schizophrenia are still largely unknown. The relative ineffectiveness of dopamine antagonists to treat some symptoms of schizophrenia has promoted many investigators to postulate the involvement of the neuronal system in the pathophysiology of this disease. It has been suggested that the dopamine-coupled adenosine triphosphate (ATP)-sensitive channels may function by hyperpolarizing cells during metabolic stress, a function that may be disrupted in people with schizophrenia. Therefore, application of potassium channel openers/activators may be beneficial in schizophrenia. Diazoxide is a benzothiadiazine derivative related to the thiazide diuretics and a potassium channel opener. The purpose of the present investigation was to assess the efficacy of diazoxide, as an adjuvant agent in the treatment of schizophrenia. METHODS: Forty-two patients who met the DSM IV criteria for chronic schizophrenia completed the study. Patients were randomized to haloperidol 20 mg/day plus diazoxide 200 mg/day (21 subjects) or to haloperidol 20 mg/day plus placebo (21 subjects) in this 8-week double-blind study. RESULTS: Although both protocols significantly decreased the score of the positive, negative and general psychopathological symptoms over the trial period, the combination of haloperidol and diazoxide showed a significant superiority over haloperidol alone in the treatment of positive and general psychopathology symptoms as well as positive and negative syndrome scale (PANSS) total scores. In addition, in the diazoxide group a rapid onset of action on the positive symptoms was observed in week 2, whereas in the placebo group there was no significant effect at week 2. No significant differences were observed between the two protocols on the negative scores. CONCLUSION: The results of this study present a novel application for potassium channel openers/activators in the neuropsychiatric disorders and diazoxide may be an effective adjuvant agent in the management of schizophrenia.     

Combination of clomipramine and nortriptyline in the treatment of obsessive-compulsive disorder: a double-blind,placebo-controlled trial

Objective: There is growing interest in investigating noradrenergic functions in obsessive-compulsive disorder (OCD) because some antidepressants with strong effects on serotonin reuptake blockade fail to relieve obsessive-compulsive symptoms. We undertook a trial to investigate whether the combination of clomipramine with nortriptyline was more effective than clomipramine alone Method: Thirty patients who met the DSM-IV criteria for OCD completed the study. Patients were allocated in a random fashion, 15 each to clomipramine 150 mg/day plus nortriptyline 50 mg/day and clomipramine 150 mg/day plus placebo Results: Although both protocols significantly decreased the scores of the Yale-Brown obsessive-compulsive scale over the trial period, the combination of clomipramine and nortriptyline showed a significant superiority over clomipramine alone in the treatment of OCD Conclusion: As this study indicates, a rapid onset of action is one of the advantages of this combination. This study supports further investigation of the noradrenergic-serotonergic hypothesis in OCD     

Effect of chronic haloperidol treatment on stimulated synaptic overflow of dopamine in the rat striatum.

In vivo voltammetry was used to assess the change in stimulated striatal dopamine overflow in response to various treatments with the dopamine receptor antagonist haloperidol. Dopamine overflow was induced with stimulating electrodes implanted in the medial forebrain bundle of anesthetized rats while dopamine concentrations were monitored with Nafion-coated, carbon-fiber microelectrodes implanted in the striatum. An acute challenge of haloperidol (0.5 mg kg-1, i.p.) given to naive animals caused stimulated overflow to increase at all stimulation frequencies (10-60 Hz), with the greatest change, 5-fold, occurring at 30 Hz. These results have been compared to those obtained in a different group of rats given daily injections of haloperidol (0.5 mg kg-1, s.c.) for 30 consecutive days. On the 30th day, dopamine striatal tissue levels and uptake kinetics were not altered by this treatment, but 3,4-dihydroxyphenylacetic acid tissue levels were elevated almost 2-fold. A challenge dose of haloperidol (0.5 mg kg-1, i.p.) administered to the animals treated with chronic haloperidol did not elicit a change in stimulated dopamine overflow. In two other groups, rats were withdrawn from 30-day haloperidol treatment for 3 days or 14 days before experimentation. Stimulated dopamine overflow concentrations in both groups were not significantly different from naive animals. When the withdrawn animals were given a haloperidol challenge (0.5 mg kg-1, i.p.), 15- and 12-fold increases in overflow for 3-day and 14-day withdrawal groups, respectively, were observed at a stimulation frequency of 30 Hz. Thus, chronic treatment with haloperidol induces long-lasting effects on the capacity of dopamine receptors to modulate dopamine release.     

Aggrenox: a fixed-dose combination of aspirin and dipyridamole

OBJECTIVE: To describe the pharmacology, pharmacokinetics, efficacy, and safety of a fixed-dose combination of aspirin and extended-release (ER) dipyridamole indicated for the secondary prevention of stroke. DATA SOURCES: Published articles and abstracts were identified from a MEDLINE search (1966-December 1999) using the search terms dipyridamole, aspirin, antiplatelet, antiaggregation, and stroke prevention. Pertinent articles written in English were considered for review. Additional articles were identified from the references of retrieved literature. STUDY SELECTION AND DATA EXTRACTION: Studies including a combination of aspirin/dipyridamole in human subjects were evaluated. Emphasis was placed on randomized, controlled trials. DATA SYNTHESIS: Aspirin is a platelet inhibitor that works by inhibiting platelet cyclooxygenase, which reduces the production of thromboxane A2. Dipyridamole is a platelet inhibitor that is thought to work in part by inhibiting platelet cyclic-3',5'-adenosine monophosphate and cyclic-3',5'-guanosine monophosphate phosphodiesterase. The active metabolite of aspirin, salicylic acid, is highly bound to plasma protein and has a plasma half-life of two to three hours. Dipyridamole is also highly bound to plasma proteins, and the ER formulation has a plasma half-life of 13 hours. The first European Stroke Prevention Study (ESPS-1) found the combination of aspirin/dipyridamole to be superior to placebo in the prevention of stroke and transient ischemic attack (TIA). The ESPS-1, however, did not include an aspirin-only treatment arm. Therefore, it was unclear whether the combination of aspirin/dipyridamole was superior to aspirin alone. As a result, a second trial was conducted that included treatment arms of aspirin alone, ER dipyridamole alone, combination therapy, and placebo. The combination of aspirin 25 mg plus ER dipyridamole 200 mg twice daily was shown in the ESPS-2 to be significantly better than either agent given individually in preventing stroke and TIAs (p < 0.001). CONCLUSIONS: The American College of Chest Physicians (ACCP) recommends aspirin 50-325 mg/d to be the initial antiplatelet of choice for the prevention of atherothrombotic cerebral ischemic events. However, with the favorable results of the ESPS-2, it may be appropriate to substitute aspirin/ER dipyridamole for aspirin alone as the drug of choice. This combination appears to have a favorable adverse effect profile. The relative effectiveness of aspirin/ER dipyridamole compared with clopidogrel and ticlopidine has yet to be determined. If alternative antiplatelet therapy is needed, the ACCP recommends clopidogrel rather than ticlopidine because of its lower incidence of adverse effects. The ACCP further states that the combination of aspirin plus dipyridamole may be more effective than clopidogrel; these agents have a similarly favorable adverse effect profile.     

Role of adenosine and N-methyl-D-aspartate receptors in mediating haloperidol-induced gene expression and catalepsy.

Acute blockade of dopamine D(2) receptors by the typical antipsychotic drug haloperidol leads to alterations in neuronal gene expression and behavior. In the dorsolateral striatum, the levels of mRNA for the immediate-early gene c-fos and the neuropeptide gene neurotensin/neuromedin N (NT/N) are significantly increased by haloperidol. An acute behavioral response to haloperidol is catalepsy, considered to be a rodent correlate of some of the immediate extrapyramidal motor side effects seen in humans. Several lines of evidence suggest a link between neurotensin induction in the dorsolateral striatum and catalepsy. We hypothesize that both striatal gene induction and catalepsy elicited by haloperidol arise from the combined effect of excitatory adenosinergic and glutamatergic inputs acting at adenosine A(2A) and N-methyl-D-aspartate (NMDA) receptors, respectively. In agreement with our previous reports, adenosine antagonists reduced haloperidol-induced c-fos and neurotensin gene expression as well as catalepsy. In agreement with other reports, the noncompetitive NMDA receptor antagonist MK-801 also reduced gene expression and catalepsy in response to haloperidol. The competitive NMDA receptor antagonist LY235959 decreased haloperidol-induced catalepsy. We show here that blocking both A(2A) and NMDA receptors simultaneously in conjunction with haloperidol resulted in a combined effect on gene expression and behavior that was greater than that for block of either receptor alone. Both c-fos and NT/N mRNA levels were reduced, and catalepsy was completely abolished. These results indicate that the haloperidol-induced increases in c-fos and NT gene expression in the dorsolateral striatum and catalepsy are driven largely by adenosine and glutamatergic inputs acting at A(2A) and NMDA receptors.     

The effect of neuroleptics on acetylcholine concentration and choline uptake in striatum: Implications for regulation of acetylcholine metabolism.

It has previously been shown that neuroleptic drugs block an apparently inhibitory influence of dopamine on cholinergic interneurons in striatum, thereby increasing acetylcholine turnover. In this study, systemic administration of the neuroleptic, fluphenazine, decreased the acetylcholine content in the striatum but not the neocortex of rats killed by focussed microwave irradiation. The effect was observed with doses of fluphenazine as low as 0.05 mg/kg, and was also seen after two other neuroleptics, spiroperidol (1 mg/kg) and haloperidol (4 mg/kg). In contrast, neither fluphenazine nor haloperidol pretreatment had any effect on the high affinity accumulation of choline by striatal synaptosomes. These observations suggest that after administration of dopamine receptor antagonists the release and metabolism of acetylcholine in the striatum is increased, but that a compensatory increase in choline uptake does not occur, thereby resulting in a temporary decrease in acetylcholine concentration. On the basis of these findings, we conclude that acetylcholine synthesis is regulated differently in the striatum than in other brain regions.     

Thallium-201 myocardial imaging in patients with coronary artery disease: comparison of intravenous adenosine and oral dipyridamole.

OBJECTIVE: To compare thallium-201 (201Tl) myocardial perfusion imaging following intravenous adenosine and oral dipyridamole. DESIGN: Open-label, randomized, comparison. SETTING: Outpatient, university-affiliated clinic. PATIENTS: Fifteen patients with angiographically documented coronary artery disease. INTERVENTIONS: Planar 201Tl myocardial perfusion imaging following both intravenous adenosine 140 micrograms/kg/min for six minutes and oral dipyridamole suspension 300 mg. MAIN OUTCOME MEASURES: A comparison between adenosine and dipyridamole was made in the following areas: concordance in interpretation of 201Tl scintigrams, cardiac and noncardiac 201Tl uptake and clearance, hemodynamic and electrocardiographic changes, and adverse effects. RESULTS: The scintigraphic studies showed perfusion defects in 13 patients (87 percent) after dipyridamole and in 15 patients (100 percent) after adenosine. 201Tl uptake and clearance were quantitated in nine myocardial segments and in four extracardiac segments in each patient. 201Tl uptake was not significantly different between adenosine and dipyridamole studies in most cardiac regions. Extracardiac 201Tl uptake was significantly less in the liver and splanchnic regions following adenosine compared with dipyridamole. 201Tl clearance was not significantly different following adenosine and dipyridamole except in the anterolateral region in the anterior view. Hemodynamic changes following administration of intravenous adenosine and oral dipyridamole were not significantly different. Adverse effects were more common with adenosine than with dipyridamole. Adverse effects with adenosine were transient; however, adverse effects with dipyridamole were prolonged and required reversal with aminophylline in 2 patients. No patients required termination of the adenosine infusion or administration of aminophylline. CONCLUSIONS: These preliminary data suggest that adenosine 201Tl imaging may be a useful alternative to dipyridamole 201Tl imaging. Although adenosine produces more frequent adverse effects, they are generally better tolerated than those associated with dipyridamole.     

Efficacy of accelerated dose titration of olanzapine with adjunctive lorazepam to treat acute agitation in schizophrenia

We conducted a prospective double-blind study of accelerated dose titration of olanzapine in the treatment of newly admitted acutely agitated patients with schizophrenia. Patients were randomized to either oral olanzapine (10 mg per day) or oral haloperidol (10 mg per day), plus lorazepam as needed (up to 12 mg per day). Antipsychotic dosage was increased to 20 mg per day as early as day 3. Patients were evaluated with the Positive and Negative Syndrome Scale (PANSS) Agitation subscale during the first 24 hours of treatment, daily for the first week, then weekly until study completion. Significant within-group improvement was demonstrated in PANSS Agitation scores for both groups as early as 1 hour after initiating therapy (-5.79 +/- 6.30 for olanzapine and -4.89 +/- 6.05 for haloperidol, P <.001). This study demonstrated that accelerated dose titration of oral olanzapine is as efficacious as oral haloperidol in reducing acute agitation in patients with schizophrenia.     

Atorvastatin, a New HMG-CoA Reductase Inhibitor as Monotherapy and Combined With Colestipol

BACKGROUND: Atorvastatin, a new HMG-CoA reductase inhibitor in clinical development has demonstrated an acceptable safety profile and marked cholesterol and triglyceride reduction at doses ranging from 10-80 mg/day. Since bile acid sequestering resins are often used in combination with HMGRIs to enhance cholesterol reduction, this trial was conducted to explore the use of atorvastatin alone and combined with colestipol in patients with primary hyperlipidemia. METHODS AND RESULTS: One hundred six patients with low-density lipoprotein (LDL) cholesterol >4.1 mM/L (160 mg/dL) and plasma triglycerides <3.9 mM/L (350 mg/dL) were randomized to treatment consisting of 20 g/day colestipol, 10 mg/day atorvastatin, or 10 mg/day atorvastatin plus 20 g/day colestipol for 12 weeks. Percent change from baseline in lipid variables were measured. The atorvastatin group showed a significant reduction in LDL cholesterol of 35% after 12 weeks. Combination therapy provided an additional 10% reduction in LDL cholesterol over that observed for atorvastatin alone. Twenty-one percent of all patients in the atorvastatin monotherapy group experienced associated adverse events compared with 60% in the combination therapy group. Ninety percent of atorvastatin monotherapy patients were compliant at every visit compared with 75% receiving combination therapy. CONCLUSIONS: Although the combination of atorvastatin plus colestipol was more effective in lowering LDL cholesterol than atorvastatin alone, atorvastatin 10 mg/day monotherapy provided a better safety profile and improved patient compliance, which may result in improved long-term cholesterol control.     

托烷司琼复合氟哌啶醇与托烷司琼单用预防术后恶心呕吐的比较

目的:比较托烷司琼复合氟哌啶醇与单独使用托烷司琼预防术后恶心呕吐(PONV)的效果.方法:选择全身麻醉下行上腹部手术患者266例,随机分为托烷司琼组(T组)和托烷司琼复合氟哌啶醇组(T + H组).采用随机双盲法于手术结束前30 min给每位受试者静脉注射托烷司琼2 mg和试验用药1 mL(可能是1 mg氟哌啶醇或1 mL生理盐水),术后采用视觉模拟评分法(VAS)评估PONV程度.手术结束后记录恶心、干呕、呕吐和两组止吐药物治疗的情况,同时记录有无烦躁、谵妄、肌张力障碍、不能静坐和锥体外系反应.结果:术后恶心发生率T组37.6%,T + H组12.0%,T + H组明显低于T组(P ＜ 0.05);术后呕吐或干呕的发生率T组11.3%,T + H组4.5%,T + H组明显低于T组(P ＜ 0.05).T + H组预防PONV的疗效明显高于T组(P ＜ 0.05),只有少数恶心患者需给予止吐药物治疗.两组手术前后Q-T间期差异无统计学意义,两组中均未出现烦躁、谵妄、肌张力障碍、不能静坐和锥体外系反应患者.结论:托烷司琼复合氟哌啶醇对于预防PONV的效果和时程明显优于单独使用托烷司琼,且不增加不良反应的发生率.     

Protective effect of rutin, a polyphenolic flavonoid against haloperidol-induced orofacial dyskinesia and associated behavioural, biochemical and neurochemical changes

The occurrence and irreversibility of tardive dyskinesia (TD), a motor disorder of the orofacial region, resulting from chronic neuroleptic treatment has been considered a major clinical issue in the treatment of schizophrenia. The molecular mechanism underlying the pathophysiology of TD is not completely known. Several animal studies have demonstrated an enhancement of oxidative damage and increased glutamatergic transmission after chronic administration of neuroleptics. The present study investigated the effect of rutin, an antioxidant in haloperidol-induced orofacial dyskinesia by using different behavioural (orofacial dyskinetic movements, stereotypic rearing, locomotor activity, percent retention), biochemical [lipid peroxidation, reduced glutathione levels, antioxidant enzyme levels (SOD and catalase)] and neurochemical (neurotransmitter levels) parameters. Chronic administration of haloperidol (1 mg/kg i.p. for 21 days) significantly increased vacuous chewing movements, tongue protrusions and facial jerking in rats, which were significantly inhibited by rutin. Chronic administration of haloperidol also resulted in dopamine receptor sensitivity as evident by a well-shaped response (initial decrease followed by increase) in locomotor activity and stereotypic rearing and also decreased percent retention time on elevated plus maze paradigm. Pretreatment with rutin reversed these behavioural changes. Besides, haloperidol also induced oxidative damage in all regions of brain which was prevented by rutin, especially in the subcortical region containing striatum. Although turnover of dopamine and noradrenaline decreased in both cortical and subcortical regions after chronic administration of haloperidol, it was significantly reversed by high-dose rutin treatment. The findings of the present study suggested the involvement of free radicals in the development of neuroleptic-induced orofacial dyskinesia, a putative model of TD, and rutin as a possible therapeutic option to treat this hyperkinetic movement disorder.     

Effects of diltiazem, dipyridamole, and their combination on hemostasis

Calcium channel blockers and antiplatelet agents, alone and in combination, have been reported to induce bleeding in patients undergoing surgery. Since diltiazem and dipyridamole influence platelet function in vitro and in vivo, their influence on hemostasis was examined in five normal men given diltiazem, 90 mg by mouth, followed by 60 mg every 6 hr for 48 hr, or dipyridamole, 75 mg by mouth every 8 hr for 48 hr. At 24 hr, the alternate drug was added to the regimen to assess effects of the combination on hemostasis. Platelet aggregation, serum thromboxane B2 and 6-keto-PGF1 alpha concentrations (stable metabolites of thromboxane A2 and prostacyclin), bleeding time, prothrombin time, partial thromboplastin time, and serum diltiazem concentrations were measured. Diltiazem and dipyridamole alone and in combination had no significant effect on bleeding time, prothrombin time, or partial thromboplastin time. Platelet aggregation induced by threshold concentrations of adenosine diphosphate, epinephrine, and calcium ionophore A 23187 were inhibited by diltiazem and dipyridamole alone and in combination. The only change in prostaglandin concentrations was a slight increase in serum 6-keto-PGF1 alpha after diltiazem. Despite influences on platelet function, neither diltiazem nor dipyridamole alone or in combination induced clinically relevant changes in hemostasis.     

Cardiac safety in the European Stroke Prevention Study 2 (ESPS2)

The second European Stroke Prevention Study investigated the prevention of stroke and/or death in 6602 patients with transient ischaemic attack or stroke with aspirin (25 mg b.d.), dipyridamole (400 mg b.d.), the combination of aspirin and dipyridamole or placebo. This post hoc analysis investigated cardiac events in patients with coronary heart disease or myocardial infarction (MI) at entry. Dipyridamole did not result in a higher number of cardiac events, e.g. angina pectoris, MI, or death from all causes. The combination of aspirin plus dipyridamole was superior to either drug alone in the prevention of stroke.     

Nicotine reduces antipsychotic-induced orofacial dyskinesia in rats

Antipsychotics are an important class of drugs for the management of schizophrenia and other psychotic disorders. They act by blocking dopamine receptors; however, because these receptors are present throughout the brain, prolonged antipsychotic use also leads to serious side effects. These include tardive dyskinesia, repetitive abnormal involuntary movements of the face and limbs for which there is little treatment. In this study, we investigated whether nicotine administration could reduce tardive dyskinesia because nicotine attenuates other drug-induced abnormal movements. We used a well established model of tardive dyskinesia in which rats injected with the commonly used antipsychotic haloperidol develop vacuous chewing movements (VCMs) that resemble human orofacial dyskinesias. Rats were first administered nicotine (minipump; 2 mg/kg per day). Two weeks later, they were given haloperidol (1 mg/kg s.c.) once daily. Nicotine treatment reduced haloperidol-induced VCMs by ～20% after 5 weeks, with a significant ～60% decline after 13 weeks. There was no worsening of haloperidol-induced catalepsy. To understand the molecular basis for this improvement, we measured the striatal dopamine transporter and nicotinic acetylcholine receptors (nAChRs). Both haloperidol and nicotine treatment decreased the transporter and α6β2* nAChRs (the asterisk indicates the possible presence of other nicotinic subunits in the receptor complex) when given alone, with no further decline with combined drug treatment. By contrast, nicotine alone increased, while haloperidol reduced α4β2* nAChRs in both vehicle and haloperidol-treated rats. These data suggest that molecular mechanisms other than those directly linked to the transporter and nAChRs underlie the nicotine-mediated improvement in haloperidol-induced VCMs in rats. The present results are the first to suggest that nicotine may be useful for improving the tardive dyskinesia associated with antipsychotic use.     

Efficacy and safety of rosuvastatin alone and in combination with cholestyramine in patients with severe hypercholesterolemia: a randomized, open-label, multicenter trial

BACKGROUND: Patients with severe hypercholesterolemia may need greater cholesterol reductions than can be achieved with statin therapy alone. OBJECTIVE: The primary objective of this trial was to compare the efficacy of a combination of rosuvastatin plus cholestyramine with that of rosuvastatin alone for reducing low-density lipoprotein cholesterol (LDL-C) levels after 6 weeks of treatment. METHODS: In this open-label, multicenter, randomized, parallel-group, comparator trial, adult patients with severe hypercholesterolemia (LDL-C level, 190-400 mg/dL) received rosuvastatin 40 mg/d for 6 weeks after a 6-week dietary lead-in period and were then randomized to 6 weeks of treatment with rosuvastatin 80 mg/d alone or rosuvastatin 80 mg/d plus cholestyramine 16 g/d (8 g BID with meals). RESULTS: Of 153 eligible patients, 147 (83 men, 64 women; mean [SD] age, 54.5 [13.7] years; mean [SD] bodyweight, 81.3 [14.4] kg) received randomized treatment, and 144 had post baseline measurements and were included in the analysis. The mean (SD) reduction in LDL-C was 522% (13.0%) after treatment with rosuvastatin 40 mg, and the least squares mean (SE) reductions in LDL-C were 56.4% (1.8%) and 60.5% (1.8%) after treatment with rosuvastatin 80 mg alone (n = 69) and rosuvastatin 80 mg plus cholestyramine (n = 75), respectively. No significant differences between treatments were found for these or other lipid measurements. Incremental LDL-C reductions >30% were obtained in 29% (22/75) of patients receiving combination therapy and 4% (3/69) of patients receiving rosuvastatin alone. The combination therapy was less well tolerated, primarily due to gastrointestinal symptoms; otherwise, the treatments were generally well tolerated. CONCLUSION: In this group of patients with severe hypercholesterolemia, the combination of rosuvastatin 80 mg with cholestyramine 16 g/d did not provide a significantly greater efficacy benefit than rosuvastatin alone.     

Haloperidol,lorazepam, or both for psychotic agitation? A multicenter,prospective, double-blind,emergency department study

Rapid tranquilization is a routinely practiced method of calming agitated psychotic patients by use of neuroleptics, benzodiazepines, or both in combination. Although several studies have examined the efficacy of the three approaches, none have compared these treatments in a prospective, randomized, double-blind, multicenter trial. Ninety-eight psychotic, agitated, and aggressive patients (73 men and 25 women) were prospectively enrolled during an 18-month period in emergency departments in five university or general hospitals. Patients were randomly assigned to receive intramuscular injections of lorazepam (2 mg), haloperidol (5 mg), or both in combination. Patients in each treatment group received 1 to 6 injections of the same study drug within 12 hours, based on clinical need. They were evaluated hourly after the first injection until at least 12 hours after the last. Efficacy was assessed on the Agitated Behavior Scale (ABS), a modified Brief Psychiatric Rating Scale (MBPRS), Clinical Global Impressions (CGI) scale, and an Alertness Scale. Effective symptom reduction was achieved in each treatment group with significant (P < .01) mean decreases from baseline at every hourly ABS evaluation. Significant (P < .05) mean differences on the ABS (hour 1) and MBPRS (hours 2 and 3) suggest that tranquilization was most rapid in patients receiving the combination treatment. Study event incidence (side effects) did not differ significantly between treatment groups, although patients receiving haloperidol alone tended to have more extrapyramidal system symptoms. The superior results produced by the combination treatment support the use of lorazepam plus haloperidol as the treatment of choice for acute psychotic agitation.     

Measurement of adenosine metabolism and uptake in smooth muscle and effects of adenosine transport inhibitors

Attempts were made to measure adenosine transport in isolated smooth muscle preparations including guinea-pig taenia caeci, beef coronary arteries and longitudinal muscle of rabbit small intestine. Because adenosine-mediated relaxation is potentiated by nucleoside transport inhibitors such as dipyridamole and 6- thiobenzylpurine ribosides in the first two systems but not in rabbit intestinal muscle, possible differences in transport capacities and in the effects of these inhibitors in the three tissues were examined. Transport was to be measured by assessing metabolic products of adenosine including adenine nucleotides and inosine plus hypoxanthine in both tissues and incubation media. Despite extensive rinsing of tissues, adenosine deaminase leaked into the incubation media, requiring its inhibition by 5 nM deoxycoformycin. When measuring apparent transport rates by quantitating metabolic products in the presence of 5 nM deoxycoformycin, no saturation of uptake at 100 to 400 microM adenosine was observed in taenia caeci and rabbit muscle. Comparing these results with literature reports on transport rates in single cell preparations, it appears that the obtained values (20-40 pmol/mg/min) may be at least 100-fold lower, suggesting that rates of diffusion through tissue and intracellular deamination of adenosine were the limiting functions measured by the methodology used in this study, requiring a careful definition for the terms transport and uptake and suggesting that it is practically not possible to measure true transport of adenosine in intact tissues. The uptake of adenosine was inhibited in all three tissues by dipyridamole and 6- thiobenzylpurine ribosides (10 microM) to a similar extent, leaving open the question of why potentiation of the relaxant effects of adenosine is seen in taenia caeci and coronary arteries but not in rabbit intestinal muscle.     

Effect of dipyridamole on zidovudine pharmacokinetics and short-term tolerance in asymptomatic human immunodeficiency virus-infected subjects.

Zidovudine delays the progression of infection and prolongs the survival of human immunodeficiency virus (HIV)-infected patients, but these benefits are limited by dose-related toxicity and the cost of the drug. Dipyridamole, in micromolar concentrations, acts synergistically with zidovudine, reducing the anti-HIV 95% inhibitory concentration of zidovudine 5- to 10-fold in vitro. We sought to establish a well-tolerated dose of dipyridamole for use in combination with zidovudine and to detect clinically significant pharmacokinetic interactions. Both objectives are essential for planning studies of the efficacy of the zidovudine-dipyridamole combination. Eleven asymptomatic HIV-infected subjects (median CD4+ cell count, 311 cells per mm3), 10 of whom had been on zidovudine at 500 mg/day for at least 6 months, were admitted to the study. Zidovudine pharmacokinetics were measured on day 1. Dipyridamole was then begun at 600 mg/day (subjects 1 to 3) or 450 mg/day (subjects 4 to 11), and zidovudine and dipyridamole pharmacokinetics were measured on day 5. All subjects given 600 mg of dipyridamole per day developed headache or nausea, or both. Six of eight subjects given dipyridamole at 450 mg/day developed headache or mild nausea that resolved after a median of 2 days. The area under the zidovudine concentration-time curve was not significantly different on day 1 in comparison with that on day 5 (P = 0.11). Symptoms were significantly correlated with the maximum zidovudine concentrations, which were achieved when dipyridamole was dosed concomitantly (p = 0.03). Total (free and protein-bound) dipyridamole trough concentrations were near those demonstrating synergy with zidovudine against HIV in vitro. Dipyridamole was highly protein bound, with a median free/total dipyridamole ratio of 0.7%; the percent free/total dipyridamole ratio was inversely correlated with alpha 1 acid glycoprotein concentrations (r2 =0.66). Results of the study indicate that adjustment of the zidovudine dose was not required to achieve equivalent zidovudine concentrations when zidovudine was administered in combination with dipyridamole at the doses studied. In the short study described here, the zidovudine-dipyridamole combinations was well tolerated in asymptomatic HIV-infected subjects after the occurrence of mild transient symptoms.