Trazodone cardiotoxicity

Management of ventricular dysrhythmia secondary to trazodone overdose

Torsades de pointes (TdP), a life-threatening ventricular dysrhythmia, was recorded in a 30-year-old woman who had taken a deliberate overdose of trazodone. The patient was successfully defibrillated to normal sinus rhythm and given intravenous magnesium sulfate according to Advanced Cardiovascular Life Support guidelines. The patient was discharged and experienced no further complications.

The electrocardiographic manifestations of cyclic antidepressant therapy and overdose: a review

Cyclic antidepressants may cause changes in the electrocardiogram at therapeutic or toxic serum levels. The most serious complications of cyclic antidepressant toxicity are dysrhythmias, hypotension, and seizures. It is predominantly the cardiotoxic effects that cause mortality. Once cardiotoxicity is evident, the treatment of choice is serum alkalinization, preferably by sodium bicarbonate therapy. In order to predict which overdose patients are at high risk for complications, electrocardiographic criteria have been identified as reliable screens. For "first generation" tricyclic antidepressants, QRS prolongation (particularly greater than 100 msec) and a terminal 40-ms frontal plane axis greater than 120 degrees are the most sensitive. This article reviews antidepressant pharmacology, electrocardiographic manifestations of antidepressant cardiotoxicity, and approaches to treatment of antidepressant-induced conduction disturbances and dysrhythmias.

The cardiovascular effects of antidepressants

This monograph comprises a review of the cardiovascular effects of the various types of antidepressant drugs in clinical use. The frequency, severity and clinical importance of these effects are placed in perspective. Most antidepressants can cause changes in blood pressure. Both the tricyclic type (TCA) and the monoamine oxidase inhibitors (MAOIs) can produce postural hypotension which may be dose-limiting. In addition, the MAOIs may be associated with severe hypertension when amine-containing foods or medicines are ingested. It is unlikely that therapeutic doses of any available antidepressant drug could impair cardiac contractility. Typical TCAs can cause abnormalities of cardiac conduction and arrhythmias, but this affects less than 5% of patients, mostly to a clinically insignificant extent. Newer compounds such as lofepramine, mianserin, trazodone and viloxazine seem safer in this respect. Reports of an association between therapeutic use of TCAs and sudden death are far from convincing. Overdosage with the MAOIs, lithium and carbamazepine is dangerous but not common; overdose with a TCA is a major source of morbidity and mortality. Lofepramine, mianserin and trazodone are relatively safe in overdose. The use of various antidepressants in patients with hypertension, cardiac failure, angina pectoris, myocardial infarction, or cardiac arrhythmias is discussed and guidelines suggested for the selection and use of antidepressant medication.

Mianserin and trazodone for cardiac patients with depression

In a placebo controlled double-blind cross-over study, the cardiovascular and antidepressant effects of three weeks' treatment with mianserin (30-80 mg daily) and trazodone (150-400 mg daily) were studied in depressed patients who had co-existant cardiac disease. In 14 of the 16 patients, no haemodynamic deterioration occurred with either drug. Two patients withdrew from the study. One with coronary artery disease, whose concomitant medication included a calcium-antagonist and a beta-adrenoceptor blocker and who developed severe postural hypotension after his first dose of trazodone while the other had an increased frequency of transient cerebral ischaemic attacks with both mianserin and trazodone, but not with placebo. Mianserin and trazodone are comparable for both antidepressant efficacy and paucity of cardiovascular effects. Although unwanted effects were generally mild, the incidence of dizziness was greater in those patients receiving trazodone. Caution is advised, however, when prescribing either drug to patients with transient cerebral ischaemic attacks or those with coronary artery disease receiving medication.

Relative toxicity of cyclic antidepressants

To compare the relative central nervous system and cardiac toxicity of amoxapine, maprotiline, and trazodone with the older tricyclic antidepressants, a three-year (1981 through 1983) retrospective review was performed on 1,313 cases involving cyclic antidepressant exposures reported to the Maryland Poison Center. Seizures were more common in the amoxapine (24.5%) and maprotiline (12.2%) groups, compared with either the tricyclic antidepressants (3.0%) or trazodone (0%) (P less than .01). A higher incidence of seizures also was observed in desipramine ingestors (17.9%) compared with other tricyclic antidepressants. No significant differences in the incidence of central nervous system depression or cardiotoxicity was found between the groups. These findings support reports of an increased incidence of seizures in overdoses of amoxapine and maprotiline, but do not substantiate claims of less cardiotoxicity.

Antidepressant drug therapy in the elderly: enhancing safety and compliance

This review article addresses some of the complex issues surrounding antidepressant drug usage among elderly depressives. While primarily geared toward the psychiatrist in general practice, the article provides useful information for the nonpsychiatric physician who is frequently called upon to evaluate and treat affective disorders in the geriatric population. Since tricyclic antidepressants and lithium are the most commonly used psychotropic drugs in the treatment of depression, their side effects and adverse reactions are discussed specifically as these relate to the elderly. Suggestions are offered on how to improve safety and enhance compliance. Brief mention is made of the monoamine oxidase inhibitors and the second generation antidepressants. Dose ranges are recommended for use of these agents in geriatric patients. Finally, a section of the article reviews the most commonly encountered encountered drug interactions between tricyclic and a variety of other psychotropic and nonpsychotropic drugs.