A double blind comparison of zimelidine and amitriptyline in endogenous depression

Monitoring of tricyclic antidepressant plasma levels and clinical response: a review of the literature. Part I

Part I of this paper presents a comprehensive review of plasma level monitoring of tricyclic antidepressants (TCAs) and their relationship to clinical response to antidepressant therapy. Imipramine, nortriptyline, amitriptyline, clomipramine and desipramine are the most widely studied TCAs in this regard. Typical therapeutic plasma concentration ranges are suggested for some of these agents, although a consensus is lacking.

A review of the safety of paroxetine

The tolerability and safety of treatment with paroxetine have been assessed by analysis of a clinical trial database that extends to 4126 patients treated with paroxetine, 1954 patients on active control, and 625 placebo patients. A total of 451 patients were exposed to paroxetine for periods of 1 or more years. Paroxetine was generally better tolerated than active control and was associated with a lower frequency of manic reactions in bipolar patients and fewer seizures than active control. Paroxetine appears to offer a differential advantage in reducing suicidal thoughts; the number of suicides and attempted suicides per patient exposure year were lower for paroxetine than for other antidepressants or placebo.

Divergence and convergence of commercial and scientific priorities in drug development: The case of Zelmid, the first SSRI antidepressant

Based on a realist conceptualization of interests, this paper explores how commercial and scientific priorities appear to have converged and diverged during the development of the antidepressant Zelmid. The drug represents the first of the selective serotonin reuptake inhibitors (SSRIs) to reach the market. Zelmid was synthesized in 1971 and launched by the Swedish firm Astra in 1982, but subsequently withdrawn the next year because of adverse neurological effects. This paper draws on in-depth interviews with scientists representing both industry and academia who had high-level involvement in various phases of the project (experimental, pre-clinical and clinical), as well as on textual sources such as scientific articles and memoirs. Zelmid was a product of mechanism-based or "rational" drug discovery from the early 1960s and the associated intermingling of science and commerce. It is argued that both scientists and the pharmaceutical company shared an interest in embracing mechanism-based drug discovery because it simultaneously promised medico-scientific advances and profits. However, the intermingling of science and commerce also strained the relationship between scientific and commercial priorities further along the trajectory of the drug; for example, concerning issues such as dosage strategy and drug use in primary care, where corporate management allegedly took decisions contrary to the recommendations of both academic and company scientists. On such occasions the asymmetry in power became apparent in scientists' narratives: commercial considerations trumped those of science since, ultimately, decisions rest with management, not with scientists. In addition, temporality appears to be associated with the divergence of commercial and scientific priorities. While rare during experimental and pre-clinical phases, divergence was concentrated downstream to the clinical testing and post-marketing phases. It is hypothesized that a similar pattern of convergence and divergence of commercial and scientific priorities may exist in the trajectory of other drugs.

Temperature regulation in depression: functional 5HT1A receptor adaptation differentiates antidepressant response

Observations in humans and animals have indicated that chronic, but not acute, antidepressant treatment (ADT) can desensitize 5-HT1A receptor-mediated responses, such as hypothermia. We hypothesized that 5-HT1A desensitization would be necessary for an antidepressant response (ADR) to occur. To test this hypothesis, we examined 5HT1A-agonist ipsapirone (IPS)-induced hypothermia in 28 depressed patients being treated with fixed doses of nortriptyline (75 mg) at 3-day and 3-week treatment points. Decreases in 24-item Hamilton scores (>12) were used to dichotomize the response data into ADR groups of 13 responders (ADR+) and 15 nonresponders (ADR-). A two-way repeated measures analysis of variance indicated significant temperature differences in the area under the curve between response groups across time from 3-day to 3-week intervals (df=1, 26, F=6.6, p<0.02). In comparison to 3 days treatment, at 3 weeks, the ADR+ patients showed blunted hypothermic responses to IPS. ADR- did not show this effect, implicating ADR+ patients to be less responsive to 5HT1A-receptor stimulation after 3 weeks treatment. Similar effects were not found for 5HT1A postsynaptically mediated ACTH and cortisol responses. These results indicate that to achieve ADR, serotonergic neurotransmission needs to be altered as reflected by the change in 5-HT1a receptor responsiveness documented herein.

Evidence for beneficial effects of antidepressants on suicidality in depressive patients: a systematic review

The role of antidepressants in suicide prevention is a major public health question, given the high prevalence of both depression and depression-related suicidality. Therefore all means available should be utilised to clarify the influence of antidepressants on suicidality. This paper gives a comprehensive overview of the positive effects of antidepressants on suicidality. In the first section, principal methodological issues related to suicidology in general as well as to clinical and epidemiological studies that investigate the influence of antidepressants on suicidality are discussed. In the second section, the results of controlled clinical studies on the efficacy of antidepressants in suicidality are presented. The third section reports on the results of other types of studies, especially epidemiological studies. Altogether, there seems to be reasonable evidence from different research approaches that antidepressants are able to reduce suicidal ideation and also suicidal behaviour in depressive patients. While the evidence for the beneficial effect on suicidal ideation comes from randomised control group studies, some of which used a placebo arm, the evidence for the prophylactic effect on suicidal behaviour, especially suicide, was primarily obtained from well-designed epidemiological studies.

Antidepressants for depressed elderly

BACKGROUND

Depression is a relatively common experience in older adults. The syndrome is associated with considerable distress, morbidity and service commitment. Approximately two thirds of patients presenting with severe forms will respond to antidepressant treatment and the last twenty years has witnessed a great increase in the number of these drugs. Older, frail people are particularly vulnerable to side effects.

OBJECTIVES

The aims of this review were to examine the efficacy of antidepressant classes, to compare the withdrawal rates associated with each class and describe the side effect profile of antidepressant drugs for treating depression in patients described as elderly, geriatric, senile or older adults, aged 55 or over.

SEARCH STRATEGY

The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR-Studies) was searched (2003-08-13). Reference lists of relevant papers and previous systematic reviews were hand searched for published reports and citations of unpublished studies.

SELECTION CRITERIA

Only randomised controlled trials were included. Trials had to compare at least two active antidepressant drugs in the treatment of depression.

DATA COLLECTION AND ANALYSIS

Reviewers extracted data independently. In examining efficacy, the reviewers assumed that people who died or dropped out had no improvement. Withdrawal rates irrespective of cause and specifically due to side effects were compared between drug classes. Relative risk (RR) for dichotomous data and weighted mean difference for continuous data were calculated with 95% confidence intervals (CI). Qualitative side effect data were reported in terms of ratios of side effects and percentage of patients experiencing specific side effects.

MAIN RESULTS

A total of 29 trials provided data for inclusion in the review. We were unable to find any differences in efficacy when comparing classes of antidepressants. However, as the trials contained relatively small numbers of patients, these findings may be explained by a type two error. Tricyclic antidepressants (TCAs) compared less favourably with selective serotonin reuptake inhibitors (SSRIs) in terms of numbers of patients withdrawn irrespective of reason (RR: 1.24, CI 1.04, 1.47) and number withdrawn due to side effects (RR: 1.30, CI 1.02, 1.64). Subgroup analyses demonstrated that TCA related antidepressants had similar withdrawal rates to SSRIs irrespective of reason of withdrawal (RR: 1.49, CI 0.74, 2.98) or withdrawal due to side effects (RR: 1.07, CI 0.43, 2.70). The qualitative analysis of side effects showed a small increased profile of gastro-intestinal and neuropsychiatric side effects associated with classical TCAs.

AUTHORS' CONCLUSIONS

Our findings suggest that SSRIs and TCAs are of the same efficacy. However, we have found some evidence suggesting that TCA related antidepressants and classical TCAs may have different side effect profiles and are associated with differing withdrawal rates when compared with SSRIs. The review suggests that classical TCAs are associated with a higher withdrawal rate due to side effect experience, although these results must be interpreted with caution due to the relatively small size of the review and the heterogeneity of the drugs and patient populations.

Pharmacotherapy of suicidal behavior in bipolar disorder

Patients with Bipolar Disorder (BD) are at particularly high risk for both attempted and completed suicides. The period of highest risk for completed suicide is during the 2 years following discharge from a hospitalization. To date, pharmacological studies of suicidal behavior in BD have been quite limited. While strong evidence has been found regarding the anti-suicidal effects of lithium, evidence for such properties in other commonly prescribed medications for BD, including anticonvulsants, SSRIs and anti-psychotics, has been largely unexplored. Considering the high risk of suicidal acts in patients with BD, further research on the pharmacotherapy of suicidal behavior is crucial.

Suicide and antidepressants

Suicidal thoughts and suicide attempts are an integral part of various depressions. Suicide attempts are common in major depression but even more common in recurrent brief depression, and the rate is further increased when these depressions occur comorbidly. Combined depression, where recurrent brief depression and major depression coexist, is the strongest clinical predictor of suicide attempts in the literature. There have been very few controlled studies of treatments for depression in high-risk groups of suicide attempters. Psychotherapy has been found to significantly raise the suicide attempt rate compared with conventional treatment, whereas fluoxetine and mianserin were not different from placebo. The only treatment that has been found to lower the suicide attempt rate in those with a history of previous suicide attempts is low doses of flupenthixol, a neuroleptic licensed for depression in Europe. This drug had a significant advantage compared with placebo in a six-month study. There are indications from large studies that maprotiline and amitriptyline might raise the suicide attempt rate, compared with placebo or other antidepressants, independent of their inherent toxicity in overdose. Several analyses of coroners' data show that tricyclic antidepressants are associated with high and unacceptable death rates in overdose compared with SSRIs and other safer antidepressants. Toxic antidepressants should be avoided in those thought to be at particular risk.

Pharmacotherapy of affectively ill suicidal patients

The development of psychopharmacologic strategies for ameliorating the symptoms associated with major psychiatric disorders is relatively recent in the history of medicine. Regarding depression, the past 30 years have seen the advent of several clinically therapeutic antidepressant medication classes. With the advent of these newer and safer antidepressants, more primary care practitioners are prescribing these drugs, and as a result, more people are being prescribed antidepressant medication than ever before. This article reviews this psychopharmacologic revolution that has emerged as a consequence of a greater understanding of the neurochemical perturbations underlying major affective disorders.

The SSRIs: advantages, disadvantages and differences

The highly specific mechanism of action of the selective serotonin re-uptake inhibitors (SSRIs) confers advantages on this group, relative to other classes of antidepressant, and thus represents a significant advance in the pharmacotherapy of depression. Whilst their clinical efficacy is equivalent to that of the tricyclic antidepressants (TCAs), the SSRIs have a greatly reduced risk of toxicity in overdose and have been shown to be significantly better tolerated. Specifically, the SSRIs have a low incidence of anticholinergic effects and are essentially devoid of cardiotoxicity. This tolerability advantage may be of significance in improving compliance and hence cost-effectiveness of treatment, particularly in the long term. Despite a lack of sedative effect, there is evidence that SSRIs are more effective than TCAs in the treatment of depression with anxiety. In addition, the SSRIs have been shown to be effective in obsessive-compulsive disorder, panic disorder and social phobia. Although superior efficacy has not been demonstrated for any one of the SSRIs, the structural diversity of this group is reflected in emerging qualitative and quantitative differences in side effects and drug interaction potential. Many of these differential features reflect important variations in pharmacological and pharmacokinetic profiles, including dosage flexibility, washout times, dose-plasma level proportionality and age-related changes in plasma levels. Fluoxetine, for example, has a considerably longer half-life than other SSRIs and side effects and drug interactions may thus occur for an extended period following discontinuation of treatment. Significant differences in the potential for drug interactions in this group are related to their relative potency for inhibition of important liver drug-metabolising enzymes including CYPIID6, CYPIA2 and CYPIIIA4. Large comparative clinical trials of the different SSRIs have yet to be undertaken; however, the differences that have already become apparent provide important information enabling the physician to choose an SSRI appropriate to the individual patient.

Lack of efficacy of fluoxetine in recurrent brief depression and suicidal attempts

Recurrent brief depression (RBD) fulfills DSM-III-R symptom criteria for major depression but the episodes are of shorter duration than the 2 weeks required by DSM-III-R. The clinical importance of the disorder has been observed in prophylactic studies of suicidal behavior. The possibility that antidepressants with selective action on the reuptake of serotonin might be effective in preventing recurrences of brief depression has been investigated. Fluoxetine in a dose of 120 mg a week, administered biweekly, had no effect on the recurrence rate, which was maintained at approximately the same rate on fluoxetine (1 every 18.7 days) as with placebo (1 every 17.6 days). In a group of patients with two or more prior episodes of suicidal behavior, there were 18 attempted suicides in the 54 patients treated with fluoxetine and the same number in the 53 patients treated with placebo. Fluoxetine neither raised nor lowered the suicide attempt rate as compared with placebo, providing no evidence to support the drug's role in either suicide provocation or prevention. Since fluoxetine is clearly effective with recurrent major depression, it would appear that recurrent brief depression has a different pharmacology.

Plasma concentrations of fluvoxamine and maprotiline in major depression: implications on therapeutic efficacy and side effects

We examined the relationship between plasma concentrations of specific acting antidepressants (fluvoxamine/maprotiline) and clinical improvement as well as the impact of the magnitude of the plasma concentration of these antidepressants on side effects. Patients (32 patients with major depression) were treated within a double-blind parallel trial for four weeks and plasma concentrations were obtained before, on days 8 and 28 of the trial. Although there was a fixed-flexible dosage design it was apparent that 16 patients (89%) of the fluvoxamine group and all patients of the maprotiline group received a dosage between 200 and 300 mg/day in the last week of the trial. Plasma concentrations (mean +/- SD micrograms/l) of fluvoxamine were 125 +/- 91 and 142 +/- 108 on days 8 and 28, respectively and the range of fluvoxamine plasma concentrations on day 28 was from 20 to 417 micrograms/l. Plasma concentrations (mean +/- SD micrograms/l) of maprotiline were 146 +/- 62 and 202 +/- 134 on days 8 and 28, respectively and the range of maprotiline plasma concentration on day 28 was from 12 to 428 micrograms/l. There was no linear relationship between plasma concentrations of both antidepressants (fluvoxamine/maprotiline) and oral dosage. Whereas there was no correlation between fluvoxamine concentration and clinical response there was a tendency that higher maprotiline concentrations were associated with a better antidepressive efficacy at the end of the trial. Higher concentrations of fluvoxamine as well as of maprotiline were significantly (P < 0.05) associated with more side effects.

Clinical and biochemical aspects of depressive disorders: III. Treatment and controversies

The present document is the final of three parts of a review that focuses on recent data from clinical and animal research concerning the biochemical bases of depressive disorders, diagnosis, and treatment. Various treatments for depression, including psychotherapy, pharmacological, and somatic treatments, will be described in this third part. Also, some of the controversies in the field, as well as a summary of the most salient points of the review, will be discussed. Previous sections of this review dealt with the classification of depressive disorders and research techniques for studying the biochemical mechanisms of these disorders (Part I) and various transmitter/receptor theories of depressive disorder (Part II).

Why do amitriptyline and dothiepin appear to be so dangerous in overdose?

Data from different analyses of reported deaths from overdose with antidepressants in the U.K. reveal that amitriptyline and dothiepin are the antidepressants most likely to be associated with death from overdose. All widely used tricyclic antidepressants (TCAs) except clomipramine and lofepramine appear to be dangerous in overdose, whereas the newer antidepressants such as mianserin, trazodone, viloxazine and the TCA lofepramine appear to be relatively safe. The toxicity of amitriptyline and dothiepin appears to be greater than all antidepressants including other TCAs and it is important to try to understand why. A number of explanations will be considered: 1. Dothiepin and amitriptyline may be inherently more toxic than other TCAs. 2. Dothiepin and amitriptyline may induce suicide more than other antidepressants. It is assumed that antidepressants are neutral with regard to inducing suicide but this may not be true. There is, for example, evidence that alprazolam and other benzodiazepines induce suicidal behaviour. 3. Amitriptyline and dothiepin are often presented in subtherapeutic and ineffective doses and it is possible that increased suicides may result from inadequately treated depression. 4. There may be a selective overreporting of deaths with amitriptyline and dothiepin. 5. Amitriptyline and prothiaden may be selectively given to the suicide prone on the mistaken assumption that they are safe.

New antidepressants and 5-HT uptake inhibitors

The efficacy of 5-HT uptake inhibitors, including paroxetine, as antidepressants is compared with that of the reference tricyclic antidepressants. It is suggested that some of the older tricyclic antidepressants might not have been released for general clinical use if tested by today's rigorous standards. Placebo-controlled, multicentre studies indicate that 5-HT uptake inhibitors are both effective as antidepressants and well tolerated by depressed patients. They also appear to have a role in the treatment of depression when associated with personality disorders, in the treatment of obsessive-compulsive disorder and bulimia, and in resistant depression. Moreover, the evidence for efficacy in the prophylaxis of depression is better established for 5-HT uptake inhibitors than for reference antidepressants.

Biochemical and pharmacological tests for the prediction of ability of monoamine uptake blockers to inhibit the uptake of noradrenaline in-vivo: the effects of desipramine, maprotiline, femoxetine and citalopram

The ability of desipramine and maprotiline (NA uptake inhibitors), as well as citalopram and femoxetine (5-HT uptake inhibitors) to protect mice against brain NA depletion induced by H 77/77 (4-alpha-dimethyl-m-tyramine), has been compared with their ability to counteract reserpine (2.5 mg kg-1)- or apomorphine (16 mg kg-1)-induced hypothermia and to potentiate TRH (40 mg kg-1)-induced hyperthermia in mice. While both NA uptake inhibitors antagonized the action of H 77/77, maprotiline being weaker than desipramine, femoxetine and citalopram were inactive. However, in contrast to citalopram, femoxetine was active in the other tests, being about twice as weak as maprotiline, which itself was several times weaker than desipramine in those tests. On the basis of the results obtained it is concluded that functional in-vivo tests for NA uptake inhibitors are more sensitive than the H 77/77 biochemical test; moreover, femoxetine, which in-vitro studies is less selective than citalopram, may inhibit the uptake of NA in-vivo.

Clinical efficacy of paroxetine in resistant depression

The antidepressant effects of a specific reuptake inhibitor of 5-hydroxytryptamine (5-HT), paroxetine, were tested in 24 patients with resistant depression who had failed to respond to conventional antidepressants after at least 4 weeks of treatment. A novel exper imental design was chosen in which all patients had 12 weeks of treatment beginning and ending with placebo therapy with 6 weeks of active drug treatment at some point in between. Ratings of depressive symptoms were made using the Hamilton rating scale (HRS) for depression, and the checklist for unwanted effects and their severity was also recorded before and during treatment at 2 week intervals. The change from placebo to active paroxetine therapy was made using a double-blind procedure. Patients who made a significant placebo response in the first 2 weeks of treatment were excluded from further analysis; 20 patients completed the study and satisfied all criteria for inclusion. Both groups of showed a significant improvement in symptoms after 4 weeks of paroxetine therapy. There were no significant treatment differences between the groups, but improvement in symptoms occurred sig nificantly later in the patients who had a longer period of initial placebo therapy. The experimental design also allowed study of withdrawal effects after stopping active treatment. There was no increase in adverse effects, including a subgroup associated with withdrawal problems, either during treatment with paroxetine or after the drug was stopped. The results suggest that paroxetine is probably an effective antidepressant, is well tolerated and has few adverse effects.

Effect of a selective serotonin uptake inhibitor in agoraphobia with panic attacks. A double-blind comparison of zimeldine, imipramine and placebo

A double-blind clinical trial of zimeldine, a potent inhibitor of central serotonin reuptake, versus imipramine and placebo was carried out on 44 patients suffering from agoraphobia with panic attacks. Zimeldine was a superior treatment on all rating scales other than a global rating scale which did not reach statistically significant superiority. Imipramine was not shown to be superior to placebo. The implications of these results for further research on the underlying pathophysiology of agoraphobia with panic attacks are discussed.

Effects of repeated zimelidine administration on sleep parameters in the rat

Seven-hour sleep EEG recordings were obtained from rats (N = 15) given a single acute dose, and rats (N = 15) given 14 daily doses of zimelidine, 20 mg/kg IP. REM latency, REM sleep, number of REM episodes, and total sleep time were significantly affected by zimelidine administration when compared to controls, as well as to each animal's baseline sleep parameters. Sleep latency and slow-wave sleep were not significantly affected by zimelidine. The results are discussed in terms of the implications of the use of zimelidine as a clinical treatment for depression, as well as the implications for the use of REM changes as a diagnostic indicator of the efficacy of treatment with zimelidine.

Double-blind comparison between a serotonin and a noradrenaline reuptake blocker in the treatment of depressed outpatients. Clinical aspects

Seventy-five outpatients with major depressive disorder (RDC) were randomly referred to treatment with a dominant serotonin (5-HT) uptake inhibiting drug (zimeldine, 100 mg b.i.d.) or a dominant noradrenaline (NA) uptake inhibiting drug, (maprotiline, 75 mg b.i.d.). The total antidepressive effect was similar in the two groups for up to 4 weeks of treatment. Both drugs gave an effect on the depressive syndrome as a whole, with no preference for mood, anxiety, retardation or vital symptoms. Good response to the NA drug correlated to few prior episodes and few years since first episode, whereas the 5-HT drug had its best effect when there were several previous episodes.

Profiles of antidepressant activity with the Montgomery-Asberg Depression Rating Scale

The Montgomery and Asberg Depression Rating Scale (MADRS) is a 10 item severity scale constructed to be sensitive to change with treatment. It was designed to be sensitive for individual items and is therefore useful for measuring differential profiles of action. The MADRS profiles of activity were examined in a six-week double-blind comparative group study of depressed patients treated with mianserin or zimeldine. Three of the ten items on the MADRS showed individual significant advantages for mianserin, reduced sleep (weeks 1 and 3), concentration difficulties (week 1), and reduced appetite (week 3). These findings are in agreement with earlier reports of poor sleep and gastrointestinal upset associated with the 5-HT uptake inhibitor zimeldine. The selective improvement in concentration difficulties and in the other items support the view that mianserin is particularly useful in alleviating the anxiety associated with depression. The sedative effect of mianserin did not appear to interfere with concentration. There were significant improvements in the mianserin-treated group at 1, 2, 3, and 4 weeks for the MADRS, Hamilton Depression Rating Scale and Clinicians Global Impression scale. There was no significant advantage for mianserin at 5 and 6 weeks. The differential clinical effects were apparent early in the study but any selectivity of action appeared to be overwhelmed by the general antidepressant effect later in treatment.

High incidence of multisystemic reactions to zimeldine

Forty-five patients suffering from a major depression were administered zimeldine, amitriptyline or placebo (15 patients in each group) in a double-blind controlled study. In the zimeldine group, seven of the 14 patients treated for more than one week presented a toxic syndrome consisting in a severe prostration, fever, myalgias and arthralgias. In all patients presenting this syndrome, laboratory analyses revealed an elevation of alkaline phosphatase and of aspartate and alanine aminotransferases and a decrease in white blood cell and platelet counts. Three patients presented a mild proteinuria and hematuria. Although an immunological mechanism cannot be ruled out, several characteristics of this reaction suggest the formation of a metabolite of zimeldine with direct cellular toxicity. The relatively high starting dose of 200 mg/day of zimeldine administered in the present study and the increment to 300 mg/day after only seven days might have contributed to the high incidence of toxic reactions observed.

Norzimelidine, a metabolite of a highly selective 5-hydroxytryptamine uptake inhibitor, can inhibit the uptake of noradrenaline in-vivo

Zimelidine and norzimelidine were tested for their ability to counteract reserpine (2.5 mg kg-1)- or apomorphine (1-16 mg kg-1)-induced hypothermia and to potentiate TRH (40 mg kg-1)-induced hyperthermia in mice. Norzimelidine produced positive results in all three tests, behaving like a weak NA uptake inhibitor. Zimelidine was practically inactive. We conclude that the weak inhibitory effect of norzimelidine on the uptake of NA (in-vitro experiments) may be of importance for its pharmacological action and for the clinical action of zimelidine.

No correlation exists between antidepressant activity and the ability of 5-HT uptake inhibitors to interact with 5-HT receptors of the rat stomach fundus strip

Several 5-HT uptake inhibitors, established and potential antidepressant drugs, were tested for their ability to counteract contractions of the rat isolated stomach fundus strip induced by 5-HT and BaCl2. Of 12 inhibitors tested, only doxepine, amitriptyline, clomipramine, imipramine, Ro 11-2465 (cyan-imipramine), citalopram and fluvoxamine antagonized the contraction induced by 10(-6) M 5-HT with IC50 values below 10(-4) M. Amitriptyline, doxepine and cyproheptadine, at concentrations inhibiting the effect of 5-HT, did not antagonize the strip contractions induced by 3 X 10(-3) M BaCl2, while the remaining compounds that antagonized 5-HT-induced contractions, also antagonized--with at least a similar potency--the contractions induced by BaCl2. From among antidepressant compounds investigated, only doxepine and amitriptyline may be regarded as antagonists of the 5-HT receptor in the rat stomach strip.

Zimeldine to geriatric patients in once daily dosage. A pharmacokinetic and clinical study

The therapeutic efficacy, tolerability and pharmacokinetics of zimeldine in elderly depressed patients were evaluated after administration of different doses of the drug in once daily evening doses. The doses of zimeldine were 100 mg during the first 2 weeks, 150 mg during the next 2 weeks and 200 mg during the last 2 weeks. Nine of the 11 patients (mean age 78 years) included in the study completed the 6-week treatment period, and all nine improved according to the Hamilton depression rating scale. The drug was well tolerated and the side effects were few and mild. No influence of clinical importance was noted in haematology, liver and kidney functions, EEG, blood pressure or pulse rate. Steady-state plasma concentrations of zimeldine, and its active metabolite norzimeldine, were achieved in most cases after 1 week of treatment in each dose regimen. The plasma concentrations increased linearly with the increase in dose. The maximal interindividual variations in plasma concentrations were 8-fold for zimeldine and 3-fold for norzimeldine . The plasma levels of both zimeldine and norzimeldine were higher in the elderly than reported earlier in younger patients. The ratio of norzimeldine/zimeldine concentrations was reduced in the elderly, indicating a reduction of the metabolic capacity. The results suggest that zimeldine can be administered in a once daily dosage regimen to elderly patients, but they should be given a lower dose than younger patients.

Assessment of the anticholinergic effects of antidepressants in a single-dose cross-over study of salivation and plasma levels

In order to evaluate the anticholinergic effect of antidepressant drugs, 11 healthy volunteers were given single oral doses of reference drug, test drugs or placebo on a double-blind basis at weekly intervals. The doses corresponded to average daily patient medications. Spontaneous whole mouth and parotid salivation, and plasma levels of drug and possible metabolites were measured 2, 6 and 10 h after drug administration. Moderate, statistically significant inhibition of salivation was found when nortriptyline, imipramine-N-oxide and mianserin were given. Less pronounced, but still statistically significant inhibition occurred after ingestion of nomifensine and zimelidine. The zimelidine effect was exclusively due to the metabolite norzimelidine, and the inhibition after imipramine-N-oxide was mainly due to the metabolite imipramine, but imipramine-N-oxide itself also had slight activity. Isocarboxazide and lithium had no effect on salivation. From these results and reported values of pharmacokinetic variables, the average level of anticholinergic activity during long-term treatment may be predicted: for mianserin and (nor-)zimelidine moderate inhibition of salivation, although less pronounced than with nortriptyline; for nomifensine no clinically significant effect; and for imipramine-N-oxide a negligible contribution from the unmetabolized drug.

A double-blind, controlled evaluation of zimeldine, imipramine and placebo in patients with primary affective disorders

Zimeldine, imipramine and placebo were studied in a randomized, double-blind, parallel group comparison of 119 patients with primary affective disorders. These out-patients were between 18 and 65 years of age and all received placebo single-blind during an initial 3-7-day washout period. During the subsequent 6-week double-blind period, patients were titrated from 50 mg b.d. to 150 mg b.d. with zimeldine, a potent and selective inhibitor of 5-HT reuptake, with imipramine, an inhibitor of noradrenaline and 5-HT reuptake, or with a corresponding number of placebo capsules. The zimeldine treatment group had significantly lower mean HAM-D scale total scores than the placebo and imipramine groups at week 4 and last available assessment. There was a significantly greater proportion of patients showing an improvement of 50% or more in HAM-D score, among the zimeldine group than in the placebo group at week 4, and among the imipramine group at weeks 4, 6 and last available assessment. The Clinical Global Impression (CGI) scales and the 56-item Hopkins Symptom Check-list (HSCL-56) self-rating inventory both showed significantly more improvement in the zimeldine patients than in the placebo or the imipramine patients. Fewer zimeldine patients reported adverse experiences than imipramine patients. Dry mouth was the most frequently reported adverse experience, occurring significantly more often in the imipramine group than the zimeldine or the placebo groups; significantly more zimeldine than placebo patients reported dry mouth. Headache was the only other adverse experience which occurred more often in the zimeldine than in the placebo group. The imipramine group had consistently higher mean pulse rates than the other two groups, and postural hypotension was also more common in the imipramine group.

Anxiety as part of depression

Changes in diagnostic criteria have shown a trend towards a broader definition of depression. Thus, a number of patients who would previously have been considered to be suffering from anxiety states are now classified as having major depressive illness according to the criteria of the Diagnostic Statistical Manual III. Despite this, such patients show a good response to antidepressant drugs (compared to placebo) if their severity of depression is above 15 on the Hamilton depression scale. It therefore seems likely that there is a common biological substrate underlying both anxiety states and depressive illness, but this issue remains somewhat controversial. The suggestion that the 5-HT system is involved in the mediation of anxiety is considered. Further evidence is required before definite conclusions can be drawn, but it seems clear that anxiolytic activity is not dependent on sedative properties.

Zimeldine in depressive illness--efficacy and safety data

Two studies of zimeldine in depressive illness are reported, one a double-blind, placebo-controlled trial, the other an open evaluation. In both studies, zimeldine was shown to have antidepressant properties. No simple relationship between plasma zimeldine or norzimeldine and clinical effect was demonstrated in eight patients treated for 6 weeks. Minor changes in electrocardiographic parameters were noted in some zimeldine patients. Side-effects attributable to zimeldine treatment were generally of mild to moderate severity and the drug was well tolerated. During the studies, one patient overdosed on zimeldine (5.2 g) and, although plasma concentrations were excessive, minimum side-effects were recorded. Two cases of suspected adverse drug reactions with zimeldine are described.

A multicentre double-blind comparative trial of zimeldine and imipramine in primary major depressive disorders

Zimeldine, a new antidepressant with a selective inhibition of 5-HT reuptake, was compared with imipramine in a double-blind comparative study. The trial was conducted on 95 patients with primary major depressive disorder, of endogenous character. During the 4-week study period clinical efficacy was evaluated by using the Hamilton Depression (HAM-D) scale, Beck's Inventory and global ratings. Zimeldine (100 mg b.d.) was shown to have as good an antidepressive effect as imipramine (50 mg t.d.s.) when evaluated on the HAM-D scale. Assessment of the symptom improvement on this rating scale suggested that zimeldine was more effective in improving the patient's insight of the disease. There was no significant difference between zimeldine and imipramine as assessed by a final global improvement rating scale as well as by the patient's own impression. Exploratory data analysis revealed that zimeldine was significantly more effective than imipramine in the following groups; patients over 40 years of age; patients whose initial onset of illness occurred at over 40 years; patients with a history of at least three episodes of depressive illness; patients with mild to moderate depression; and patients who had previously failed to show an appreciable response to other antidepressant treatment. Analysis of global safety ratings revealed that zimeldine is significantly safer than imipramine, with a lower incidence of adverse symptoms involving the autonomic nervous system, especially anticholinergic reactions. No significant difference was observed between the two groups with respect to abnormal laboratory reports. One zimeldine patient developed symptoms suggesting a hypersensitivity reaction (fever, skin eruption and elevation of plasma levels of transaminases), which led to the patient's withdrawal from drug treatment.

The safety of zimeldine in long-term use in depressive illness

The aim of this study was to evaluate the safety of zimeldine, a 5-HT reuptake inhibitor, in the long-term treatment of depressive disorders. The study was an open label, multicentre investigation involving 147 patients who were suffering from depressive illness and who needed long-term anti-depressant treatment. Sixty-five patients completed the intended treatment period of 1 year, 75 terminated prematurely, and 7 are still in the programme. The reasons for termination were mainly ineffectiveness of the drug and adverse reactions. During the long-term treatment the most common emergent symptoms were, in order of decreasing frequency, dizziness, dry mouth, sleep disorders, sweating, tremor, nausea and headache. The side-effects were, however, mild and they generally decreased during the treatment period. No new adverse symptoms were reported. In the long-term treatment group, body weight showed a slight mean decrease. Clinical chemistry and cardiovascular investigations were judged to show no changes of clinical importance. It is concluded that zimeldine was shown to be a safe drug in this 1-year treatment programme of depression.

The new antidepressant zimeldine in general practice. A surveillance study of 15,000 patients

The safety and efficacy of zimeldine--the 5-HT reuptake blocker--was investigated in a 3-week open surveillance study of 15,000 out-patients with depressive illness. In general, a single daily dose of 200 mg of zimeldine was given to adults for a minimum of 3 weeks. Patients of 65 years or over received 100 mg. The drug was well tolerated and troublesome side-effects occurred in only a small percentage of patients. No previously unencountered side-effects or new pattern of side-effects emerged from this study. The general impression of the efficacy of zimeldine confirmed previous findings (i.e. that zimeldine is an effective antidepressant).

Comparison between zimeldine and amitriptyline of efficacy and adverse symptoms--a combined analysis of four British clinical trials in depression

The similarities and differences in the clinical response and incidence of adverse symptoms between zimeldine and amitriptyline have been evaluated by use of a combined analysis of four double-blind clinical trials in depression. In total, 197 patients were included in this series of studies. The efficacy of the drugs was assessed using the Hamilton Rating Scale for Depression (HAM-D). Reports of adverse symptoms were actively elicited by use of a check-list of symptoms and rated for severity. The overall clinical efficacy of the two drugs was shown to be equivalent with a high degree of statistical confidence. However, there exist differences in the profile of action. Amitriptyline has a significant advantage in insomnia problems. In spite of this zimeldine was shown to be at least as effective as amitriptyline in reducing anxiety. Amitriptyline is associated with significantly more anticholinergic side-effects, whereas headache is more disturbing during zimeldine treatment. The combination of several independent trials based on similar protocols can be a useful tool to increase the statistical reliability of conclusions relative to that which can be achieved in standard sized, individual studies in depression.

Zimelidine: a placebo-controlled trial in depression

Twenty-eight hospital inpatients with a primary major depressive disorder were treated with either zimelidine or placebo. Patients were matched for age, sex, and initial severity of depression and assigned double blind to the treatment regimen. An initial dosage of 150 mg/day was used for up to 6 weeks. Zimelidine was significantly more effective in alleviating the symptoms of depression than placebo, with 82% of zimelidine and 25% of placebo patients showing clinical improvement. There were few complaints of severe side effects in zimelidine-treated patients, and few effects on the cardiovascular system. Two zimelidine-treated patients were withdrawn for suspected drug-related adverse events. Zimelidine was a safe, effective antidepressant in this group of patients.

A double-blind evaluation of zimelidine in comparison to placebo and amitriptyline in patients with major depressive disorder

This paper presents the results from a large multicenter study, performed at three clinical research units in the USA. Prior to a three to seven days of placebo washout period, patients were randomly assigned to zimelidine, a potent and selective 5-HT reuptake blocker, amitriptyline or placebo. The scheduled treatment period was four weeks. Dosage range was 75-300 mg/day for active medications. The rating instruments were the Hamilton Depression Scale and the Clinical Global Impression scale. The side effects were recorded by using a side effect inventory (TESS). Vital signs, laboratory work including clinical chemistry, ECG, and plasma levels of drugs, were performed. In the main efficacy evaluation there were 229 depressed outpatients included, all having completed at least two weeks of treatment after the washout period. The patients treated with zimelidine as well as those treated with amitriptyline showed a significant improvement relative to the placebo treated patients. For the safety evaluation 263 patients were included. Side effects, in particular anticholinergic effects but also drowsiness and cardiovascular effects, were much less pronounced in the zimelidine group as compared to the amitriptyline group. Only marginal differences regarding side effects were reported for zimelidine compared to those reported for placebo.

Effects of acute doses of zimelidine on REM sleep in rats

Sleep EEG (7 h) were obtained from 11 rats given 5, 10, and 20 mg/kg zimelidine, and a control dose of saline. Zimelidine significantly suppressed REM sleep, lengthened REM latency, and reduced total sleep time (TST) in a dose-dependent manner. Sleep latency was not affected except at the highest dose of zimelidine. Slow-wave sleep (SWS) was not affected at any dose. The results are discussed in terms of their implication for the use of zimelidine in the clinical treatment of depression.

A double-blind comparison of zimelidine and amitriptyline in depressive out-patients

A double-blind, randomized clinical study was conducted in thirty-four out-patients suffering from major depressive disorders comparing zimelidine with amitriptyline. The dosage was flexible, maintenance doses varying between 50-150 mg in the amitriptyline group and 50-300 mg in the zimelidine group. After a wash-out period of at least a week the mean score in Hamilton Rating Scale for depression (HRS) was 22.2 for zimelidine and 21.9 for amitriptyline. During the treatment period of 6 weeks, zimelidine and amitriptyline appeared to be equally effective as antidepressants in HRS and Global Ratings. The zimelidine group showed significantly less somnolence and dry mouth. No clinically important changes were seen in the laboratory parameters during the study.

A double-blind study of zimelidine, a serotonin uptake inhibitor, and desipramine, a noradrenaline uptake inhibitor, in endogenous depression. I. Clinical findings

A comparative evaluation of zimelidine, a potent and selective serotonin (5-HT) uptake inhibitor, and desipramine, a potent noradrenaline (NA) uptake inhibitor, was carried out in a 4-week randomized, double-blind study in 65 hospitalized patients with endogenous depression. For evaluation of the clinical effect, Hamilton Rating Scale for depression (HRS) and a 14-item scale chosen from the Comprehensive Psychopathological Rating Scale (CPRS) were used. The concentration of drug in plasma was determined on the same days as the clinical ratings. There were no significant difference in the overall therapeutic effect between the two drugs. However, zimelidine had significantly better effect on anxiety. Although both agents were well tolerated, the zimelidine-treated patients reported significantly less severe anticholinergic side effects. Body weight did not change significantly in either treatment group. In the total material ther were no significant correlation between plasma concentrations of zimelidine, norzimelidine and desipramine and the amelioration score of either HRS and CPRS.

Zimelidine: comparison of different dosage regimes in general practice

Various studies have demonstrated that depressive symptoms are a frequent and important problem in general practice. Zimelidine has been shown to have effective antidepressant activity. A controlled double-blind trial was set up to compare the efficacy and side effects of zimelidine when given as a single daily dose (200 mg night or morning) and when given as a divided dose (100 mg b.d.). These three dosage schedules were studied. The trial was conducted among patients attending their general practitioners and suffering from a depressive disorder. Using one of the three dosage schedules, these patients were treated with zimelidine for a minimum period of 6 weeks. Symptom severity was measured by means of the Hamilton Rating Scale for Depression and the side effects assessed using an adverse event record and a symptom checklist. The findings are discussed.

The antidepressant efficacy of zimelidine and maprotiline

In a double-blind group comparison study of 39 patients with primary depressive illness zimelidine in a dose of 200 mg at night demonstrated the same order of antidepressant efficacy as maprotiline in a dose of 150 mg at night after either two or four weeks treatment measured by the amelioration or final score on the Hamilton Rating Scale (HRS) and on the Montgomery & Asberg Depression Rating Scale (MADRS). Both zimelidine and maprotiline demonstrated significant antidepressant activity at 2 weeks compared with 2 weeks prior treatment with placebo measured by amelioration on HRS (paired t 4.1 P less than 0.001, t 2.7 P less than 0.02) or MADRS (paired t 3.5 P less than 0.005, t 5.1 P less than 0.001). An item analysis of the MADRS showed significantly better sleep and appetite in the maprotiline-treated group compared with the zimelidine-treated group which is in accord with the pharmacology of the two compounds.

Zimelidine vs maprotiline in depressed outpatients. A preliminary report

Outpatients with endogenous depression diagnosed according to the research diagnostic criteria of Feighner et al. were randomly referred to treatment with zimelidine (100 mg b.i.d., group Z) or maprotiline (75 mg b.i.d., group M). Patients who did not respond to treatment by days 28 were crossed over to the other drug. This preliminary report comprises results up to day 28 and includes antidepressive effect as rated by CPRS and globally, side effects, clinical chemistry and ECG. Ratings were double-blind at days 0, 7, 14 and 28, and a washout period of 4--7 days preceeded the trial. Group Z includes 27 and group M 28 patients with equal distribution of sex, age, duration of present episode, initial severity, etiology and previous course. There were 11 dropouts in group M and 5 in group Z due to side effects or treatment failure. On the other hand, 8 patients in group Z had to cross over to the other drug versus 2 in group M. According to the total CPRS score and the global score the antidepressive effect was somewhat better in group Z at 2 weeks but similar at 1 and 4 weeks. Group Z is less sedative but still seems to have a better anti-anxiety effect. Side effects were on a low level. There was a greater number of patients in group Z who complained of nausea, vomiting, loose stools, sleep disorder and sweating, and in group M dry mouth, drowsiness, dizziness and accomodation difficulties. Chemical analyses and ECG showed slight and inconsistent changes.