Psychosis After Switch in Opioid Maintenance Agonist and Risperidone-Induced Pisa Syndrome: Two Critical Incidents in Dual Diagnosis Treatment

Methadone Withdrawal-Induced Psychosis: A Case Report

Methadone is a synthetic full µ-opioid receptor agonist and N-methyl-D-aspartate antagonist given to patients who have recently stopped using illicit opioids or are tapering off chronic opioid pain medication. Maintenance treatment with methadone is today the most widespread and effective way to treat opiate addiction, which achieves abstinence, decreases morbidity and mortality, improves quality of life, and reduces crime genesis, among other benefits. It is also approved by the Food and Drug Administration for treating moderate-to-severe pain that remains unresponsive to nonopioid medications. Patients sometimes abruptly discontinue the medication for several reasons and sometimes suffer distressing but non-life-threatening withdrawal symptoms. More common withdrawal symptoms include anxiety, agitation, rhinorrhea, nausea, and vomiting, like other opioid agonist medications. Psychosis has been reported in some rare cases of methadone withdrawal. However, more research is required because, although psychotic symptoms have been described in different case reports after the reduction or withdrawal of methadone, they have not been sufficient. This case report contributes to the literature on rare manifestations of psychosis in patients who abruptly discontinue the use of methadone.

Atypical antipsychotic drugs in dual disorders: current evidence and clinical guidelines

BACKGROUND

Concurrent disorder or dual diagnosis refers to a combination of substance use disorders and mental disorders that occur in the same patient simultaneously. These conditions pose significant clinical and healthcare impacts and are often underdiagnosed, undertreated, and complex to manage.

OBJECTIVE

We assessed the quality of current pharmacological recommendations for the management of dual diagnosis, particularly by evaluating the use of second-generation antipsychotics (SGA).

METHOD

A literature search was performed using the PubMed and Scopus databases for publications up to September 21, 2021, without any time restrictions. The following search strings were used: (aripiprazole OR brexpiprazole OR cariprazine OR paliperidone OR risperidone OR quetiapine OR clozapine OR olanzapine) AND (psychosis OR schizophrenia OR schizoaffective) AND ("substance use disorder" OR cocaine OR alcohol OR cannabis OR heroin OR "double diagnosis" OR "dual diagnosis")) NOT (animal OR rat OR mouse) NOT (review or meta-analysis).

RESULTS

The search produced a final set of 41 articles. Most patients were males and were affected by schizophrenia, with cannabis the most abused substance, followed by alcohol. Aripiprazole was the most used drug, either orally or by long-acting formulations, followed by risperidone with oral and long-acting formulations, clozapine, olanzapine, and quetiapine.

CONCLUSION

The findings highlight the use of SGA for the treatment of psychotic symptoms in comorbidity with substance use. Future studies on people with dual diagnosis and focused on long-term evaluations are warranted and need to investigate the efficacy of newly introduced molecules, such as partial D2 agonists and long-acting injectable antipsychotics.

Opioid use and schizophrenia

PURPOSE OF REVIEW

To summarize the current literature regarding comorbid schizophrenia and opioid use disorder (OUD).

RECENT FINDINGS

Epidemiological evidence is unclear on whether patients with schizophrenia have a higher rate of OUD. Patients with OUD have been shown to have a higher risk of developing schizophrenia. However, it is clear that patients with both schizophrenia and OUD are less likely to receive standard of care including medication-assisted treatment (MAT) for opiate use disorder and have worse outcomes compared with patients with schizophrenia who do not abuse opioids. OUD significantly increases the risk of converting patients from prodromal schizophrenia states to schizophrenia or schizoaffective disorder. Shared pathophysiology involving the kappa opioid receptor may help explain the relationships between schizophrenia and OUD. Second-generation antipsychotics, long-acting injectables, and MAT for OUD should be utilized in a dual-diagnosis and treatment approach for patients with schizophrenia and OUD.

SUMMARY

Exploration into the relationship between schizophrenia and opiate abuse is still in its infancy and requires a significant amount of future attention to clarify the epidemiology of this comorbidity, neurobiological relationship, shared genetic underpinnings, and possible treatments for both the psychotic symptoms and substance abuse.