Are selective serotonin re-uptake inhibitors associated with an increased risk of self-harm by antidepressant overdose?

A retrospective analysis of antidepressant poisonings in the emergency department: 11-year experience

Between 1993 and 2004, patients with antidepressant poisoning admitted to an emergency department (ED) were analysed retrospectively with regard to demographics, clinical findings and treatment attempts. Age, gender, suicide attempts, classification of antidepressants, Glasgow Coma Scale (GCS) score, ECG findings, need for endotracheal intubation, follow-up period and Antidepressant Overdose Risk Assessment (ADORA) criteria were analysed by SPSS software. A total of 356 antidepressant poisoning cases were evaluated. Tricyclic antidepressants (TCA), especially opipramol and amitriptyline, were the most common agents (58.4%). The most frequent ECG finding was sinus tachycardia (40.7%, n=145). Endotracheal intubation was required in 9.6% of cases. Patients with TCA ingestion had a longer observation time in the ED, abnormal ECG findings, abnormal physical examination findings and more ADORA criteria, than patients who ingested selective serotonin re-uptake inhibitors (SSRI) (P=0.008, P=0.008, P<0.001, P<0.001). It was found that the patients who ingested TCA (P=0.001), poisoned with amitriptyline (P=0.001), patients with GCS scores of 8 and less (P=0.001), patients with two or more ADORA criteria (P=0.001), with seizures (P=0.001), with abnormal ECG (P=0.012), and patients with a history of two or more suicide attempts were intubated more frequently. Suicide attempts, classification of the antidepressant, ECG findings, seizure, GCS score and number of detected ADORA criteria affect the need for intubation in patients with antidepressant poisoning.

Drug-induced hyperkinetic movement disorders by nonneuroleptic agents

Hyperkinetic movement disorders are characterized by excess movement, and include chorea, akathesia, asterixis, dystonia, tremor, myoclonus, and tics. A wide variety of pharmacologic agents may induce or exacerbate these disorders. Neuroleptic-induced tardive dyskinesia and levodopa-induced hyperkinesia are the most common causes of medication-induced chorea. However, several nonneuroleptic agents, including antidepressants and antiepileptic medications, may also worsen hyperkinetic movement disorders. Over-the-counter medications, such as analgesics and antiheartburn medications, have also occasionally been implicated as causing hyperkinetic movement disorders. Most information regarding drug-induced hyperkinetic disorders comes from case reports and anecdotes, rather than controlled clinical trials. Further research with larger controlled trials needs to verify many of these findings.

A comparative study of non-fatal self-poisoning with antidepressants relative to prescribing in three centres in England

BACKGROUND

Antidepressants are used frequently in non-fatal self-poisoning. There are national guidelines for prescribing antidepressants. There have been few investigations of how non-fatal self-poisoning with antidepressants varies in relation to prescribing and to patient characteristics.

METHODS

A comparative study of the use of specific antidepressants (amitriptyline and dosulepin (tricyclics), citalopram, fluoxetine, paroxetine and sertraline (selective serotonin reuptake inhibitors) and venlafaxine (serotonin norepinephrine reuptake inhibitor)) for non-fatal self-poisoning (episode-based), relative to prescribing, in three centres in England, 2004 to 2006.

RESULTS

There was marked variation between centres in the ratio of rates of self-poisoning to prescribing for specific antidepressants. Higher rates of self-poisoning relative to prescribing for all antidepressants combined, and for venlafaxine, were found in the centre with greater proportions of patients with a history of self-harm and/or previous psychiatric treatment. Within each centre, higher rates of self-poisoning relative to prescribing were found for citalopram and fluoxetine than amitriptyline. However, rates of self-poisoning relative to prescribing for either amitriptyline or dosulepin were also similar to sertraline, which is of concern given the known toxicity of tricyclics.

LIMITATIONS

An ecological study, where prescriptions were for all indications and not specifically for the patients who self-poisoned.

CONCLUSIONS

Marked differences found in ratios of self-poisoning with antidepressants to levels of prescribing, in three centres in England, are likely to reflect differences in both prescribing practices (despite clear national guidance) and patient characteristics. Risk of overdose and toxicity should be considered when local prescribing policy and clinical practice relating to antidepressants are under review.

QTc intervals in drug poisoning patients with tricyclic antidepressants and selective serotonin reuptake inhibitors

Commonly used agents of drug poisoning among patients who come to the emergency services are tricyclic antidepressants (TCAs). These drugs may cause defect in cardiac conduction due to the slowdown in the cardiac depolarization and expansions in the QT interval. Selective serotonin reuptake inhibitors (SSRIs) are less expansion of the QT period and lower cardio toxic side effects. The aim of this study was to investigate QTc intervals and prognosis of the patients who come to the emergency service due to TCA and SSRI group antidepressant drug poisoning. In a study of 96 patients, 75 of whom were diagnosed to be poisoned by TCAs (TCA group) and 21 by SSRIs (SSRI group) were examined. Electrocardiographic alterations and QTc intervals all of patients were evaluated. QTc intervals of patients in TCA group were determined to be slightly more than those in SSRI group and it was not statistically significant. In the SSRI group, only one patient had QTc period more than 500 milliseconds (520 milliseconds); however, TCA overdose showed 9 (12%) patients with QTc interval over 500 milliseconds, and QTc values of 2 patients were over 600 milliseconds. In our study, it was determined that SSRI group drugs caused similar expansion of the QTc period as TCA drugs but they did not reach high values like TCA drugs, and their OTc intervals stayed in more innocent levels.

EJCP and clinical toxicology: the first 40 years

INTRODUCTION

The European Journal of Clinical Pharmacology is now 40 years old and its history and development parallel developments in the related discipline of clinical (medical) toxicology. The journal has published many papers over its history that have informed its readers of scientific advances that link clinical pharmacology and clinical toxicology.

DISCUSSION

This review will provide an overview of the developments in treatment of poisoning and how effects of poisoning may provide information for drug regulation and suggests ways in which developments in pharmacogenetics and metabolomics may stimulate future research in this area.

[Intoxication with a tricyclic antidepressant]

A 48-year-old woman with a major depression and treatment with doxepin was found comatose in her flat. Her son last saw her 48 h prior to being found. On arrival of the emergency physician, she presented a generalized seizure. The patient underwent endotracheal intubation and mechanical ventilation due to respiratory insufficiency and severe cyanosis. Empty packages of tablets (doxepin ca. 4000 mg and zolpidem 100 mg) were found in the flat. On hospital admission the doxepin blood concentration was 1.2 microg/ml. No life-threatening arrhythmia occurred at any time. On the advice of the poison information center, hemoperfusion was performed for extracorporeal elimination. Within several hours the doxepin blood concentration could be lowered to 0.8 microg/ml and although still above the therapeutic range the patient was extubated. However, the patient developed a generalized seizure which required re-intubation. As a consequence of the high distribution volume and re-distribution phenomena, the doxepin blood concentration had increased again to 1.2 microg/ml. Approximately 72 h later she was extubated again while the doxepin blood concentration was 0.9 microg/ml and 3 days later, the doxepin blood concentration was lowered to 0.3 microg/ml and the patient was transferred to the psychiatric ward the following day. This case report questions the efficacy of hemoperfusion during acute doxepin intoxication in the given constellation of a non-life-threatening arrhythmia.

Frequency of different anti-depressants associated with suicides and drug deaths

From each case of suicide and drug-related death autopsied in the Institute of Forensic Medicine, Munich during the years 2001--2005, a toxicological investigation on anti-depressants (AD) was performed. In 180 suicides and 72 narcotic drug death cases, ADs were detected: 4 different classic tricyclic anti-depressants (TCAs), 6 other non-selective monoamine re-uptake inhibitors (NSMRIs), 5 selective serotonin re-uptake inhibitors (SSRIs) and 3 other ADs. The suicides were grouped further according to the type of suicide (violent or non-violent). The prescription frequency of the ADs in Germany, expressed as the defined daily dosages (DDDs), during the investigated years served for comparison. There were serious differences in the frequency of different ADs regarding to the manner of suicide. In cases associated with doxepin and trimipramine, non-violent suicides were distinctly over-represented, as in cases in which the drug itself was responsible for the death as in cases of non-violent suicides in other manners. In contrast, in cases with citalopram or opipramol, violent forms of suicides were significantly over-represented. For amitriptyline, the ratio was approximately balanced. For the remainder of the ADs, the case numbers were too low for a valid evaluation. The different frequency distributions of the ADs, associated with violent and non-violent suicides may be explained by their different pharmacological active profiles and the different lethality of overdoses of the different ADs. There was no indication at all for a special suicidal problem of SSRIs in juveniles. Amongst 1,127 suicides within 5 years, in an area with approximately 5 million people, the youngest suicide victim with SSRIs was 28 years old. In drug death cases, citalopram was obviously over-represented.

Is there evidence for negative 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 available means should be utilised to clarify the influence of antidepressants on suicidality, especially in view of the ongoing intensive debate about possible suicidality-inducing effects of antidepressants that may outweigh their traditionally hypothesised beneficial effects. This paper gives a systematic and comprehensive review of the empirical data which might indicate that antidepressants have negative effects on suicidality. First, principal methodological issues related to this research question are discussed. Thereafter, the results of controlled trials and epidemiological and cohort studies are presented. Altogether, there seems to be only a small amount of evidence from different research approaches that antidepressants, not only serotonin reuptake inhibitors (SSRIs), might induce, aggravate or increase the risk of suicidal ideation and suicide attempts. As to suicide, there are no hints in this direction. TCAs have a higher risk of fatal outcome in overdose compared to SSRIs, which, in case of mono-intoxication, carry almost no risk of lethal consequences. The ongoing discussion about suicidality-inducing effects should not prevent physicians from prescribing SSRIs and other antidepressants to their patients if they are clinically indicated. However, they should take into account potential risks and manage them by good clinical practice.

Selective serotonin reuptake inhibitors and suicidality in juveniles: review of the evidence and implications for clinical practice

This article reviews the existing evidence regarding whether selective serotonin reuptake inhibitors increase suicidal behaviors in children and examines the implications of the findings for clinical practice and research. When balanced against the fact that depression in the young is a serious, recurring condition that produces personal suffering and can lead to suicide, the overall weight of the evidence favors pharmacologic treatment over nontreatment in moderate to severe depression. Nevertheless, the need for careful clinical monitoring of suicidality and attention to behavioral activation, manic switching, and medication compliance or withdrawal are clearly warranted.

Newer antidepressants: evaluation of fatal toxicity index and interaction with alcohol based on Finnish postmortem data

Finnish postmortem toxicology data from 1995 to 2002 was analyzed to obtain improved estimates of fatal toxicity indices for the newer antidepressants and to evaluate their interaction with alcohol. Altogether 284 fatal poisonings were attributed to 12 different newer antidepressants. Venlafaxine, mianserin, moclobemide, and mirtazapine were responsible for significantly more deaths than expected from their sales. Their fatal toxicity indices were higher than those of selective serotonin reuptake inhibitors (SSRIs) but lower than those of tricyclic antidepressants. In fatal poisonings involving alcohol in combination with venlafaxine, mianserin, moclobemide, or mirtazapine, the median blood alcohol concentration (BAC) ranged from 2.35 to 2.7 mg/g, whereas in those involving alcohol in combination with citalopram or fluoxetine the median BAC was 2.9 and 3.4 mg/g, respectively. The BAC was significantly lower in venlafaxine-related deaths than in those involving fluoxetine or citalopram. We conclude that among the newer antidepressants differences are present both in toxicity and in interaction potential with alcohol. The SSRIs appear to present a low risk of fatal poisoning when taken alone or in combination with alcohol, whereas venlafaxine is associated with an elevated risk.