Dyskinesia associated with amoxapine antidepressant therapy: a case report

Extrapyramidal symptoms associated with cyclic antidepressant treatment: a review of the literature and consolidating hypotheses

Extrapyramidal symptoms (EPS) including parkinsonism, akathisia, dystonia, and tardive dyskinesia have commonly been associated with acute or chronic administration of neuroleptic drugs. A review of the medical literature reveals a substantial number of cases with similar clinical characteristics associated with the tricyclic antidepressants, monoamine oxidase inhibitors, and selective serotonin reuptake inhibitors (SSRIs). Although the data are not sufficient to make definitive pharmacoepidemiologic conclusions, the available number of case reports suggests the SSRIs may be more common offenders in producing these adverse drug effects. The exact mechanism is elusive but likely involves complex interactions of dopamine, serotonin, and norepinephrine between cortical structures and the basal ganglia. The final common pathway for production of EPS seems to be indirect modulation of dopaminergic function. Predictors of patients at risk for antidepressant-induced EPS are not established, but a greater awareness of the potential for these drug side effects to occur may increase their recognition and decrease antidepressant-induced morbidity.

Orofacial dyskinesia: caused by antidepressants?

A case report is presented of a 72 year old woman, who has been treated for a depression with amitriptyline. During the treatment an orofacial dyskinesia develloped. Data in the literature concerning a possible link between the manifestation of orofacial dyskinesia and treatment with antidepressants were mainly found to be case reports. A closer study of the total in all of 25 case reports reveals that the antidepressant is often at most one of more possible determinants of the movement disorder. Particularly, it was frequently noted that patients were treated with other drugs or that the use of other drugs was not specified. A controverse exists in the literature whether or not a so called spontaneous orofacial dyskinesia is found in high frequency in elderly people. For clinical practice the advice is given that, in case an orofacial dyskinesia arises during antidepressant treatment, attention should be paid to other provoking factors in the first place.

Amoxapine-induced tardive dyskinesia

A case report of amoxapine-induced tardive dyskinesia following discontinuation of amoxapine therapy is reported. During 68 weeks of therapy, the patient received a maximum of amoxapine 400 mg/d. Six months after amoxapine discontinuation, the patient continued to have symptoms of tardive dyskinesia. These symptoms correlate with the dopamine receptor-blocking property of amoxapine and its metabolites. We propose that amoxapine therapy be monitored for the long-term as well as the short-term adverse effects of dopamine receptor-blockade.

Second generation antidepressants: a comparative review

The authors review four "second generation" antidepressants (maprotiline, amoxapine, trazodone, and nomifensine) in terms of action on biogenic amines and receptors, antidepressive efficacy, and adverse effects. Doxepin is used as a comparative agent and is similar to the prototypical tricyclic agents in all the above categories. Maprotiline is a selective noradrenergic agent, but shares a similar adverse effect profile with doxepin and may be associated with a high frequency of seizures in overdose. Amoxapine is a mixed action antidepressant with significant neuroleptic activity in vivo. Its adverse effect profile is highlighted by symptoms related to its neuroleptic activity, and seizures and acute renal failure in overdose. Trazodone is a selective serotonergic agent with low anticholinergic activity, and minimal morbidity/mortality in overdose. Reports of priapism, leading to impotence in some men, however, is of concern. Nomifensine is a potent noradrenergic and dopaminergic agent with low anticholinergic activity, and minimum cardiotoxicity and low morbidity/mortality in overdose. Its most important adverse effects include overstimulation and infrequent, usually reversible, immunologic hypersensitivity reactions. Trazodone and nomifensine have favorable profiles for use in the elderly. Trazodone may be more favorable in the anxious/agitated patient due to its sedative effects, whereas nomifensine may be more beneficial in the retarded, apathetic patient.

Amoxapine failure--a neuroleptic property?

Amoxapine, a member of the dibenzoxazepine drugs which includes loxapine, has recently been introduced for the treatment of depression. We present five cases of amoxapine failure after an initial good response, which showed severe deterioration with an increase in dosage. The dopamine-blocking effects of amoxapine metabolites are discussed. The mechanism of failure may be related to either the appearance of akinetic depression or a strong neuroleptic effect.