Occurrence of priapism with risperidone-paroxetine combination in an autistic child

A Case of Priapism in a Child With Autism Spectrum Disorder, Possibly Due to Risperidone Treatment With Addition of Atomoxetine

OBJECTIVES

Risperidone is an effective drug used for the treatment of irritability in children with autism spectrum disorder (ASD). Atomoxetine (ATX) is a well-tolerated drug used in first-line therapy in children with attention-deficit/hyperactivity disorder (ADHD). However, uncommon adverse effects of risperidone and ATX are a concern among mental health professionals. To our knowledge, this is the first case report of priapism after addition of ATX upon existing treatment with risperidone.

METHODS

Written informed consent for publication was obtained from the patient and his parents, and their identities were concealed for ethical reasons.

RESULTS

Here, we report a case of priapism as an adverse effect of ATX and risperidone treatment in a 7-year-old boy with ASD and comorbid ADHD. In this case, priapism was not observed with risperidone until ATX was added.

CONCLUSIONS

Priapism is a condition viewed as a medical emergency. Although risperidone-induced priapism is a rare phenomenon, it is advised for clinicians to consider the drug interactions in treatment of ASD and ADHD in terms of early diagnosis and intervention.

Risperidone-induced priapism: a case report and literature review

Priapism is a rare pathological condition defined as painful and persistent penile erection that is unrelated to sexual stimulation. It can be classified as ischaemic or non-ischaemic. Many causes have been attributed to ischaemic priapism, including the use of some medications such as antipsychotics. The mechanism of priapism associated with antipsychotics is thought to be related to alpha-adrenergic blockage that is mediated by the alpha receptors in the corpora cavernosa of the penis. In this paper, we describe a case of a patient who suffered from Risperidone-induced priapism, and how this adverse effect was resolved by switching to olanzapine followed by olanzapine pamoate. A literature search on PubMed/Medline up to 2011 was conducted by some doctors from London and found 30 cases of priapism associated with risperidone. Based on this work, we searched PubMed through 2021, using the keywords 'priapism' and 'risperidone' and found a total of 43 cases of priapism involving risperidone. Priapism is not correlated with the dosage of this psychotropic drug, and has also occasionally occurred when risperidone has been used in conjunction with another drug. The question of choosing a replacement antipsychotic after the first one has induced priapism, remains problematic. It would be preferable to switch to a drug with less marked alpha1-blocking properties, but no consensus has been reached as to the best choice of medication. Finally, any prescription of an antipsychotic treatment must be preceded by a careful interrogation in search of risk factors for priapism, and the patient should be made aware of the possible occurrence of this side effect and the need to then seek urgent medical advice.

A Review of Antipsychotics and Priapism

INTRODUCTION

Pharmacologically induced priapism is now the most common cause of priapism, with approximately 50% of drug-related priapism being attributed to antipsychotic usage. The majority of pharmacologic priapism is believed to result in ischemic priapism (low flow), which may lead to irreversible complications, such as erectile dysfunction. It is imperative that prescribing physicians be aware of potentially inciting medications.

OBJECTIVES

To identify medications, specifically antipsychotics, associated with priapism and prolonged erections and understand the rates and treatment of these side effects.

METHODS

A PubMed search of all articles available on the database relating to priapism, prolonged erections, and antipsychotics was performed.

RESULTS

Various typical and atypical antipsychotic drugs (APDs) have been implicated in pharmacologically induced priapism. In addition to dopaminergic and serotoninergic receptors, APDs have affinities for a wide array of other receptors in the central nervous system, including histaminergic, noradrenergic, and cholinergic receptors. Although the exact mechanism is unknown, the most commonly proposed mechanism of priapism associated with APDs is α-adrenergic blockade in the corpora cavernosa of the penis. Priapism appears in only a small fraction of men using medications with α1-receptor-blocking properties, indicating differential sensitivities to the α-blocking effect among men, and/or additional risk factors that may contribute to the development of priapism. The best predictor for the subsequent development of priapism is a past history of having prolonged and painless erections. The acute management algorithm of APD-induced priapism is the same as for other causes of low-flow priapism.

CONCLUSION

Clinicians should educate patients treated with antipsychotics about the potential for priapism and its sequelae including permanent erectile dysfunction. Appropriate patient education will raise awareness, encourage early reporting, and help reduce the long-term consequences associated with priapism through early intervention. Hwang T, Shah T,Sadeghi-NejadH. A Review of Antipsychotics and Priapism. Sex Med Rev 2021;9:464-471.

Ninety-six hours ordeal of priapism induced by paroxetine--A case report and literature review

Priapism is a rare but severe medical condition of sustained and painful erection of penis in the absence of any sexual stimulation, in which the penis does not return to a flaccid state. It is considered to be a medical emergency because without treatment it can lead to permanent damage and fibrosis of penis and in the long run to impotency. Albeit that there is no uniform consensus regarding the duration of sustained erection, an erection lasting more than 4 h is generally considered as an emergency which needs immediate medical attention and care. Priapism is commonly associated with iatrogenic, pharmacologic, underlying medical, or traumatic causes. In this report, we present the case of a 42-year-old African American man who developed priapism after three weeks of therapy with paroxetine which lasted for more than 96 h before coming to the attention of his health-care providers. This case is unique in that there are no reports in literature of an erection lasting for such a long duration following therapy with paroxetine. The objective of this report is to highlight the importance of recognizing the possibility of priapism with selective serotonin reuptake inhibitors in general and paroxetine in particular since this condition is not commonly seen in clinical practice to be associated with selective serotonin reuptake inhibitors and may go unrecognized. Also, potential biological mechanisms involved in the development of paroxetine-induced priapism are presented.

Risperidone, quetiapine and chlorpromazine may have induced priapism in an adolescent

Priapism is the prolonged, painful erection of penile tissue not accompanied by sexual arousal. Priapism has been established as a rare adverse drug reaction to drugs such as antipsychotics, psychostimulants, antidepressants, and mood stabilizers. Immediate intervention is needed to prevent destructive and irreversible complications, such as erectile dysfunction, disfigurement, inability of the penis to stay erect, and related social/emotional problems. Antipsychotic-induced priapism may result from the alpha receptor occupancy property of those drugs. We report the case of a 13-year-old suffering from attention deficit-hyperactivity disorder plus conduct disorder with priapism related to antipsychotics. Episodes occurred with risperidone plus methylphenidate, quetiapine plus methylphenidate, and chlorpromazine alone.

Priapism associated with risperidone: a case report, literature review and review of the South London and Maudsley hospital patients' database

Priapism is a urological emergency defined as persistent penile erection that is unrelated to sexual stimulation and typically involving only the corporal cavernosa. It can occur as a rare side effect of antipsychotic medications and is mediated via their α-adrenergic antagonist effect. In this paper we describe a case of priapism in a patient started on risperidone and sodium valproate. We also review the South London and Maudsley Case Register Interactive Search database to assess how many other cases of priapism were reported in patients taking risperidone. We add this information to a literature review of cases of priapism associated with risperidone.

Priapism in antipsychotic drug use: a rare but important side effect

Priapism is a rare but important side effect of antipsychotic drugs which may evolve into a urological emergency. Most antipsychotic drugs are alpha-1 adrenergic antagonists, which is thought to be the principal mechanism involved in antipsychotic-induced priapism. Other aetiologies exist, however. A case is presented with multiple episodes of priapism during the use of several different antipsychotic drugs. The case is representative of many patients treated with antipsychotic drugs, as there were hyperprolactinemia, and illicit drug use, which are known causes of priapism. Moreover, the patient used combinations of antipsychotic drugs. The case thus illustrates the etiological complexity which could delay a diagnosis of antipsychotic-induced priapism, and the problem of establishing a link between priapism and one particular ingredient of a drug combination. The case presents how a treatment regimen was finally established balancing antipsychotic efficacy to acceptable side effects and offers guidance to physicians regarding how antipsychotic-induced priapism may be resolved.

Priapism associated with atypical antipsychotic medications: a review

Priapism defined as persistent, painful and prolonged penile erection, was previously thought to be associated only with the use of the older, conventional first generation or typical antipsychotic medications as well as some other medications, notably, trazodone. The mechanism of priapism associated with antipsychotics is not clear but is thought to be related to alpha-adrenergic blockage that is mediated by the alpha receptors in the corpora cavernosa of the penis. Atypical antipsychotics, also known as second-generation antipsychotics, owing to their favorable side effect profile, are being prescribed with increasing frequency and are not as frequently considered to cause priapism. Some case reports reporting this side effect with their use, however, are found. Pubmed and Ovid databases were searched to obtain all articles and case reports of antipsychotic drug-induced priapism. Key search words included 'priapism', 'antipsychotics' and 'drug-induced priapism'. References of all identified studies were also reviewed. A total of 50 publications were obtained. Most of the atypical antipsychotics have been reported to cause priapism. These cases have occurred in patients shortly after having been started on the antipsychotic medications as well as in those who have been on them for an extended period of time without modification in dosage, and have also occurred sometimes, with the addition of another antipsychotic, lithium or serotonin-specific reuptake inhibitor. Priapism has been documented with nearly all the atypical antipsychotic medications. It is, however, a rarely reported side effect and therefore, underappreciated. Priapism can cause irreversible erectile dysfunction and is a urologic emergency. Clinicians should monitor patients on these medications for this rare, yet significant side effect. Furthermore, caution must be used when adding new drugs to the regimen and patients should be closely monitored for this side effect. Educating patients about the risk of developing priapism would help increase awareness of the side effect and promote early reporting thereby, decreasing long-term morbidity.

Risperidone-induced priapism

A 31-year-old patient suffering from schizophrenic psychosis was treated with risperidone, and developed priapism which required surgical intervention and resulted in long-term erectile dysfunction.