Priapism associated with zuclopenthixol

Priapism induced by various psychotropics: A case series

Objective: Priapism is a rare adverse effect of several psychotropics. Both, typical and atypical antipsychotics, as well as trazodone are known to cause priapism. The mechanism is still not fully understood, however, the most common assumption is that priapism occurs due to the α-adrenergic blocking effects of the drugs. Methods: Here we present from the AMSP database 19 cases of priapism being likely caused by a variety of psychotropics. We further reviewed case reports in order to find similarities and to identify risk factors. Results: Several patterns emerged: common was the introduction of a specific drug to a patient resulting into the immediate development of priapism, as well as a change in drug plasma concentration due to a change of drug dosage or due to comedication with certain SSRIs. Conclusion: However, priapism can occur at nearly any age and with any dose. Clinicians must be aware of the risk and reports of early signs, such as prolonged erections, should be taken seriously.

Large-scale elucidation of drug response pathways in humans

Elucidating signaling pathways is a fundamental step in understanding cellular processes and developing new therapeutic strategies. Here we introduce a method for the large-scale elucidation of signaling pathways involved in cellular response to drugs. Combining drug targets, drug response expression profiles, and the human physical interaction network, we infer 99 human drug response pathways and study their properties. Based on the newly inferred pathways, we develop a pathway-based drug-drug similarity measure and compare it to two common, gold standard drug-drug similarity measures. Remarkably, our measure provides better correspondence to these gold standards than similarity measures that are based on associations between drugs and known pathways, or on drug-specific gene expression profiles. It further improves the prediction of drug side effects and indications, elucidating specific response pathways that may be associated with these drug properties. Supplementary Material for this article is available at www.liebertonline.com/cmb.

[Priapism associated with antipsychotic medications: a series of four patients]

INTRODUCTION

Ischemic (veno-occlusive, low flow) priapism is a painful and persistent penile erection unrelated to sexual desire or stimulation. In some cases, it is an adverse event of antipsychotic medications.

MATERIAL

Between 1st January 2000 and 30th September 2007, four men (range 25/55 years), treated with antipsychotic agents (amisulpride, clozapine, levomepromazine, olanzapine, pipotiazine, risperidone or zuclopenthixol), presented one or several episodes of ischemic priapism. No other etiological factor was diagnosed. The patients were treated with aspiration and irrigation of the corpa cavernosa with intracavernous injection of sympathomimetic drugs followed in one case by a surgical distal cavernoglanular shunt.

DISCUSSION

Many conventional or atypical antipsychotic agents have been reported to cause priapism. Drug-induced priapism comprised of about 30% of the cases and an estimated 50% of them occurred with antipsychotic agents. The mechanism of priapism associated with antipsychotics agents thought to be related to alpha-adrenergic blocking properties. The decision of whether to restart a patient on a specific antipsychotic agent after an episode of priapism is a difficult clinical decision. An agent with low peripheral alpha-adrenergic blocking affinity would be preferred.

CONCLUSION

Ischemic priapism is an urologic emergency. Clinicians should be familiar with this rare but serious adverse event of antipsychotic agents to avoid long-term sequelae including erectile dysfunction.