Effect of zotepine on dopamine, serotonin and noradrenaline release in rat prefrontal cortex

The present study examined the effect of zotepine, an atypical antipsychotic, on the in vivo release of monoamines in the prefrontal cortex of rats using microdialysis. Local perfusion of zotepine at 10 microM increased extracellular levels of serotonin (5-HT), as well as dopamine and noradrenaline, in the prefrontal cortex. However, systemic administration of zotepine did not affect 5-HT release, although it increased the dopamine and noradrenaline release. These results suggest that the prefrontal 5-HT system does not contribute to the antidepressant effect of zotepine. The difference in the effect of zotepine between local and systemic treatment is discussed.

Two case studies of hypothermia induced by an increased dosage of zotepine in a combination therapy

The purpose of the present paper was to remind physicians that hypothermia is a possible side-effect of combining zotepine, valproate,and benzodiazepine. Two cases of hypothermia occurred after combining the use of zotepine, valproate, and benzodiazepine. The valproate was under therapeutic blood level when zotepine dosage was raised to 200 mg/day, and hypothermia occurred. The dosage of zotepine might constitute a positive correlation with hypothermia. The combination of zotepine, valproate or benzodiazepine may cause hypothermia as a side-effect.

[Atypical neuroleptics: new approaches to drug therapy of schizophrenic disorders]

The introduction of conventional antipsychotics revolutionized the management of psychotic disorders in the 1950s. The use of these agents has been marked by several shortcomings, including their association with severe motor disturbances and their limited efficacy in treating the negative and cognitive symptoms of schizophrenia. Patients noncompliance has largely been the result of subjectively distressing extrapyramidal motor side-effects (EPMS). It was therefore necessary to develop antipsychotic drugs with selective pharmacological profiles, e.g. limbic selectivity. A defining characteristic of atypical neuroleptics is a higher ratio of serotonin receptor blockade to D2 receptor blockade. Their primary advantage is their superior side-effect profile. The implications of EPMS reduction touch several domains of pathology in schizophrenia such as short- and long-term movement disorders, noncompliance, relapse rate, negative symptoms and cognitive dysfunction. Novel antipsychotics may represent the second pharmacological revolution in the treatment of psychotic disorders. There is, however, still a need for a critical evaluation of the risk-benefit-ratio of differing atypical agents.

Single oral dose kinetics of zotepine and its relationship to prolactin response and side effects

The authors investigated the single oral dose kinetics of zotepine and its relationship with prolactin response and side effects in 14 healthy male volunteers. Each subject took a single oral 25-mg dose of zotepine, and plasma concentrations of zotepine, prolactin, and their side effects were monitored up to 36 hours after dosing. The means +/- SD of the time of maximal plasma concentration (tmax), the apparent oral clearance, the apparent volume of distribution, and the elimination half-life (t1/2) were 3.8 +/- 1.2 hours, 4.6 +/- 4.2 1/h.kg, 109.0 +/- 59.0 1/kg, and 21.0 +/- 8.9 hours, respectively. The change in prolactin concentrations and side effect scores were parallel with that of drug concentrations, although no significant correlation was found between these three parameters at any time-point. The current results clearly indicate that the tmax and t1/2 of zotepine are much longer than those previously reported, which are reflected in the changes in prolactin concentrations and side effect scores.

Relative contribution of alpha 1-adrenoceptor blocking activity to the hypotensive effect of the novel calcium antagonist monatepil

Monatepil, a novel calcium antagonist, has alpha 1-adrenoceptor blocking activity; in the present study, we examined the relative contribution of this alpha 1-blocking activity to its hypotensive effect. Monatepil and diltiazem produced dose-dependent hypotensive effects in anesthetized rats with the same potency. Prazosin and monatepil inhibited the L-phenylephrine (L-PE)-induced pressor response, whereas diltiazem scarcely did. The injection of prazosin produced a decrease in blood pressure (BP) in anesthetized rats. The decrease was recovered with angiotensin II (AII) infusion in a dose-dependent manner. We developed a new rat model by first intravenously injecting prazosin and then infusing AII in anesthetized rats. In this model, diltiazem produced the same hypotensive effect as it did in pretreated conditions, although the hypotensive effect of monatepil was attenuated by 20-35% as compared with pretreated conditions. These results suggest that monatepil exerts alpha 1-adrenoceptor blocking action in vivo and 20-35% of the hypotensive effect of monatepil is attributed to its alpha 1-adrenoceptor blocking activity.

The efficacy of monatepil, a new calcium antagonist, in the treatment of essential hypertension

A multicenter, open-label trial in Japan examined the efficacy, safety, and optimal dose of monatepil (AJ-2615) as monotherapy and in combination therapy with angiotensin-converting enzyme (ACE) inhibitors or beta-blockers. Patients with essential hypertension who had never been treated or had been refractory to conventional antihypertensive agents were enrolled in the trial. During a 4-week control period patients assigned to monotherapy received placebo and those assigned to combination therapy received an ACE inhibitor or beta-blocker and placebo. Patients with systolic blood pressure (BP) > or = 160 mm Hg and diastolic BP > or = 95 mm Hg at the end of the control period were enrolled in the study. The initial dose of monatepil was 30 mg/day in monotherapy and 15 mg/day in combination therapy; the daily dose was titrated to 60 mg/day according to the antihypertensive response. The treatment period was 8 to 12 weeks. Blood pressure decreased from 168 +/- 8/100 +/- 6 to 142 +/- 9/85 +/- 7 mm Hg (SD) with monatepil monotherapy, from 171 +/- 11/102 +/- 6 to 141 +/- 9/84 +/- 6 mm Hg in combination with ACE inhibitors, and from 175 +/- 13/102 +/- 7 to 153 +/- 21/91 +/- 9 mm Hg in combination with beta-blockers (P < .001). When patients in whom mean BP decreased by > or = 13 mm Hg were defined as responders, the response rate was 80.4%, 78.1%, and 51.6% in the respective groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacotherapy of delusional depression: experience with combinations of antidepressants with the neuroleptics zotepine and haloperidol

The combination of an antidepressant with a neuroleptic is standard pharmacotherapy for delusional depression today. The neuroleptics used are rarely specified: occasionally haloperidol or perphenazine are mentioned. In two different open-treatment studies, consecutively admitted delusional depressed inpatients received a butyrophenone [haloperidol, bromperidol, approximately 10 mg/day (n = 16)] or zotepine [150-200 mg/day (n = 15)] as a neuroleptic in combination with a tri- or tetracyclic antidepressant (amitriptyline, maprotiline, 150 mg/day). There was a significant improvement in both groups in the sum score of the Hamilton depression scale (24-item version), in a subscore of so-called delusional items (items 2, 17, 19, 20, 23, and 24 together), in the subscore of remaining items and also in most single items such as mood, inhibition, agitation, feelings of guilt or hopelessness.

Preventive effect of a new calcium antagonist, monatepil, on drug-induced ischaemic electrocardiographic changes in rats

1. The preventive effects of monatepil, a new calcium antagonist with alpha 1-adrenoceptor blocking activity, on ischaemic electrocardiographic changes in rat models of vasospastic angina were evaluated and compared with those of the existing calcium antagonists (diltiazem, verapamil, nicardipine and nifedipine). 2. In order to assess the contribution of the alpha 1-adrenoceptor blocking action of monatepil to its anti-vasospastic action, the anti-ST depression effect of prazosin, an alpha 1-adrenoceptor blocker, was also examined. 3. Monatepil given orally (3-30 mg/kg) inhibited vasopressin (0.2 IU/kg, i.v.)-induced ST depression which is considered to indicate ischaemic electrocardiographic changes in a vasospastic angina. This effect of monatepil was more potent and long-lasting than that of diltiazem, and was similar to that of verapamil and nicardipine. At a dose of 30 mg/kg, monatepil produced a significant inhibition, even at 7 h after administration. 4. Monatepil given intravenously (0.3 mg/kg) exerted a significant inhibitory effect on methacholine (16 micrograms/kg, intracoronary arterial administration; i.c.a.)-induced ST elevation which seems to be caused by coronary vasospasm. This effect was more potent or equipotent to those of the existing calcium antagonists. 5. These results indicate that monatepil produces the preventive effect on the drug-induced ischaemic electrocardiographic changes in rats and suggest that monatepil may have potential for the treatment of vasospastic angina.

Anti-arrhythmic effects of a new calcium antagonist, monatepil, AJ-2615, in experimental arrhythmic models [corrected]

1. To characterize the anti-arrhythmic properties of a new calcium antagonist, monatepil [corrected], AJ-2615, the preventive effects of AJ-2615 were compared with those of the existing calcium antagonists, diltiazem and verapamil, in experimental models of arrhythmia. 2. AJ-2615 (0.1-3.0 mg/kg, i.v.) suppressed ventricular arrhythmias induced by adrenaline (10 micrograms/kg, i.v.) in rats. AJ-2615 (0.1 mg/kg per min for 2 min, i.v.) also suppressed atrial tachycardia induced by aconitine (0.01% aconitine solution) in rats. 3. In these activities, AJ-2615 was comparable to or more potent than diltiazem and verapamil which are widely used for the treatment of arrhythmia. 4. In pro-arrhythmic activity, AJ-2615 was less potent than diltiazem and verapamil. 5. These results suggest that AJ-2615 would be a safer anti-arrhythmic agent, with less proarrhythmic liability than diltiazem and verapamil.

[Therapeutic and adverse effects of zotepine and their relationships with serum kinetics of the drug]

The spectrum of therapeutic and adverse effects of zotepine and their relationships with serum concentrations of the drug were investigated in 28 schizophrenic inpatients by a fixed-dose (100 mg/day for the first 1 wk and 200 mg/day for the following 3 wk) study. The mean % improvement in Brief Psychiatric Rating Scale (BPRS) scores were 63.4% for total, 64.4% for positive, 41.8% for negative and 74.2% for anxiety-depression symptoms, suggesting that zotepine has a broad therapeutic spectrum. There were significant differences in improvement of negative symptoms after 1 wk and total and positive symptoms after 2 wk (P < 0.05) between responders (more than 50% reduction in total BPRS scores at wk 4) and nonresponders. The mean scores of UKU Side Effect Rating Scale were low in this study. UKU scores of psychic at wk 2 and total adverse effects at wk 3 and wk 4 (P < 0.05) were higher in nonresponders than in responders. A negative correlation between % improvement in total BPRS and total UKU scores was observed (P < 0.05). These two results suggest some relationship between poor clinical response and increased adverse effects during zotepine treatment. Lack of close correlation between serum drug concentrations and clinical or adverse effects indicates that therapeutic monitoring of zotepine concentrations would be of little significance.

[Double-blind comparison of 3 x 75 mg zotepine und 3 x 4 mg haloperidol in acute schizophrenic patients]

To assess the efficiency/risk ratio, fixed doses of zotepine and haloperidol were compared by means of a double-blind study in acute schizophrenics over a 4-week period. The assessment tools were BPRS, CGI, and the Simpson-Angus scale for the extrapyramidal disturbances, and a free report on side effects. No differences between the groups were found in respect of efficacy. According to the Simpson-Angus scale, the patients who had been treated with zotepine achieved better values, this being a general trend. There were significant differences according to the free report on side effects. Especially at onset of treatment, the patients treated with zotepine complained of tiredness. Partly marked extrapyramidal disturbances were seen in the patients who had been treated with haloperidol.

Determination of amidepin in human plasma by reversed-phase high-performance liquid chromatography with fluorescence detection

An isocratic reversed-phase high-performance liquid chromatographic method for the determination of amidepin has been developed. The method is based on the extraction of alkaline plasma with diethyl ether-dichloromethane, and the injection into the Supelcosil LC-18 column of the evaporated and reconstituted organic phase. After separation, detection is carried out by a fluorescence detector (excitation at 195 nm with no filter). The limit of detection is 10 ng/ml of plasma. The mean coefficient of variation is 12%. The plasma levels after oral administration and after intravenous administration are shown.

Zotepine, a neuroleptic drug with a bipolar therapeutic profile

Zotepine, a new tricyclic compound, was investigated in 20 schizophrenic patients in two different dosage groups. Group I (n = 8) received Zotepine in a high dosage of 270 mg +/- 37 mg/die. The other group (group II; n = 12) received a low dosage of 168 mg +/- 15 mg/die. In both groups 2 patients dropped out before the end of the treatment period because of clinical deterioration. In both groups, Zotepine manifested a rapid antipsychotic effect, good tolerability, and sedative properties during the initial days. Additionally there was a stronger positive influence on negative symptoms in the group with low dosage treatment.

Report on a double-blind comparison of two different regimens of dothiepin (prothiaden)

Thirty patients diagnosed as suffering from endogenous depression were entered into a 3-week double-blind trial comparing three times a day dosage of dothiepin with a single night-time dosage in a dosage range of 75 mg to 225 mg per day. The trial was conducted on in-patients and assessments were made pretrial and after 1 and 3 weeks. The patients were assessed by clinician-rated scales for psychomotor and psychic symptoms and by Zung's self-rating scale. Fifteen patients received dothiepin three times a day (day-time group) and fifteen received it as a single night-time dose (nocte group). There were two withdrawals in the day-time group and three in the nocte group. All withdrawals were due to lack of therapeutic effect. Over the 3-week trial 67% of the day-time group and 47% of the nocte group showed a clinical improvement. It was found that there was no statistically significant difference between the two methods of treatment. In the day-time group seven patients and in the night-time group nine patients suffered from side-effects. No particular pattern of side-effects emerged. There were no drug-related changes in the laboratory results. It was concluded that the therapeutic effect of both dosage regimes should be regarded as equivalent. Advantages, due to the specific action of dothiepin, compared with classical antidepressants for reference, could, however, not be presumed by the clinical impression.

A comparison of the therapeutic and cardiovascular effects of a single nightly dose of Prothiaden (dothiepin, dosulepin) and Lentizol (sustained-release amitriptyline) in depressed elderly patients

This was a single-blind 4-week parallel group comparative trial in fifty depressed patients. Twenty-five patients received 50 mg of Lentizol, a sustained-release form of amitriptyline, and twenty-five received 75 mg of Prothiaden. Both groups took their drugs as a single night-time dose. Patient response was measured on a symptom check-list which was completed by the doctor and a self-rating depression scale. Tolerance was assessed by recording volunteered and observed side-effects and also by taking the pulse, blood pressure and an electrocardiogram before treatment and after 2 and 4 weeks. A statistically better response was seen with Prothiaden at each follow-up assessment (1, 2 and 4 weeks) compared to Lentizol as measured by both the symptom check-list and the self-rating scale. Less side-effects was also seen with Prothiaden. Minor changes were seen in the ECG records of two patients on Prothiaden and three on Lentizol. These changes were not associated with any clinical change in the patients' cardiovascular state. No consistent changes of any clinical significance were seen in the pulse and blood pressure recordings.

Clinical trial comparison of a sustained release form of amitriptyline with dothiepin

A double-blind between-group trial was undertaken in fifty depressed patients to compare the efficacy of a sustained release form of amitriptyline (Lentizol) with dothiepin (Prothiaden) over a 5-week period. Patients fulfilling defined admission criteria were randomly allocated to treatment with evening dosage of either 50 mg of the sustained release preparation or 75 mg of dothiepin for the first week of the trial. Subject to review as necessary, these dosages were doubled at the end of the first week. Both drugs effected significant and appreciable improvement over the 5-week period, with the mean responses at the end of the trial retaining the same relative positions as at the beginning.

Tiopinac in rheumatoid arthritis: a three-phase dose-ranging, efficacy, and aspirin-withdrawal protocol

We designed a clinical trial to obtain dose-ranging, efficacy, and aspirin-withdrawal data on tiopinac in patients with rheumatoid arthritis. To accomplish this without exposing the patients to risk of disease exacerbation and avoiding type II error, we used a 3-phase protocol adding tiopinac to current therapy. The 3 phases-open-label dose ranging, double-blind tiopinac versus placebo, and aspirin withdrawal-began after a single-blind run-in period. The manufacturer withdrew tiopinac from investigation because of toxicity at higher doses, but with only 13 patients we found that tiopinac (up to 300 mg/day) decreased walking time, painful joints, and morning stiffness and increased grip strength (p less than 0.05). Both the global evaluation by the investigators and patient ratings of their activity showed superiority of tiopinac (tiopinac: 5 better, 1 worse; placebo: 1 better, 6 worse; p = 0.028 by Fisher's exact test). Complete aspirin withdrawal could be accomplished in only 3 patients, although in 10 of 13 the dose could be reduced 50% of baseline or less. The 3-phase protocol indicated effectiveness, a dose range, and partial aspirin replacement with minimal patient risk.

An evaluation of a once daily dosage régime of dothiepin hydrochloride (prothiaden)

This paper reports on the use of a single daily dose of dothiepin hydrochloride (Prothiaden). The results from a metabolism study using [14C] dothiepin were used to calculate the daily variations in blood levels after once daily and thrice daily dose regimes. A clinical study on the use of a single daily dose of 75 mg of dothiepin showed this type of regime to be well tolerated and efficacious in the treatment of 105 depressed patients in general practice. Compared to a thrice daily regime the once daily dose appeared to be more beneficial on symptomatic insomnia during the early treatment period.

A single-blind comparative study of once daily dothiepin ("Prothiaden") and divided daily doses of amitriptyline

Forty-eight patients took part in a single-blind clinical trial comparing a once daily dose of dothiepin (75 mg) and 25 mg 3-times a day of amitriptyline. The results showed that dothiepin caused a greater improvement than amitriptyline after 4 weeks of treatment as judged by depression scores, total scores and global assessments. The incidence of side-effects was less with dothiepin and in those patients who actually reported side-effects the severity was much less with dothiepin than with amitriptyline.