Clozapine prescribing in COVID-19 positive medical inpatients: a case series

Change in absolute neutrophil count after COVID-19 infection in patients using clozapine versus other antipsychotics

It was reported that patients who contracted COVID-19 while taking clozapine exhibited a distinct hematological response. However, the absence of control groups made it difficult to attribute it to clozapine. The changes in absolute neutrophil counts (ANCs) during the 4 weeks after COVID-19 infection were compared between the two groups of patients with severe mental illnesses (SMIs) (49 patients using clozapine and 54 using other antipsychotics) using generalized additive modeling. Although the pattern of a transient drop in ANC followed by gradual recovery could be demonstrated in both groups, it was more pronounced in the clozapine group ( P  = 0.00025). Nevertheless, overall ANC remained at a higher level in the clozapine group. The results suggested potential interaction between clozapine and COVID-19 at the level of hematological dynamics. However, it did not necessarily indicate that such interaction is inevitably harmful or dangerous. It was more of a concern that some patients using other antipsychotics exhibited decreased ANC, which did not easily recover. Traditionally, clinicians have been concerned about the worsening of hematological side effects in clozapine patients after COVID-19 infection. However, the obtained result highlighted the necessity of hematological monitoring in patients using any type of antipsychotics for SMIs.

Drug-Drug Interactions Between COVID-19 Treatments and Psychotropic Medications: An Updated Study

The recent evolution of coronavirus disease 2019 (COVID-19) treatments has created challenges for healthcare providers in terms of new potential interactions between these COVID-19 treatments and psychotropic drugs in patients with psychiatric disorders. Current clinical practice guidelines on managing interactions between psychotropic medications and COVID-19 treatments do not account for the newer COVID-19 medications. There is a need for updated patient management recommendations that take into account drug interactions between psychotropic drugs and the latest pharmacological approaches to COVID-19 treatment. A search of literature pertaining to drug interactions and outcomes in patients concurrently prescribed COVID-19 treatments and psychotropic medications was conducted. Drug databases were also analyzed to screen for interactions. Our review focuses on the most recent and effective COVID-19 treatments, including PaxlovidTM (nirmatrelvir/ritonavir), remdesivir, dexamethasone, tocilizumab, and baricitinib. The study provides condensed and easily interpretable tables for healthcare providers to screen for potentially harmful drug interactions. We discuss the implications of our findings on appropriate treatment plan selection by healthcare providers for patients taking select antipsychotics, antidepressants, mood stabilizers, and benzodiazepines while receiving COVID-19 treatments. Notably, PaxlovidTM may interact with several medications, particularly antipsychotics and anxiolytics, necessitating close monitoring and, in some cases, reconsideration of use. We find that dexamethasone, remdesivir, tocilizumab, and baricitinib have fewer reported interactions with psychotropics, and while some monitoring is necessary, no major adjustments are recommended for their administration in conjunction with psychotropic medications. These findings underscore the importance of careful consideration and monitoring when combining COVID-19 treatments with other medications to mitigate the risk of adverse interactions and ensure patient safety.

COVID-19: Brain Effects

Severe acute respiratory syndrome coronavirus 2, the novel coronavirus responsible for the coronavirus disease (COVID-19), affects the brain. Neurologic and neuropsychiatric symptoms may manifest in the acute and post-acute phases of illness. The vulnerability of the brain with aging further increases the burden of disease in the elderly, who are at the highest risk of complications and death from COVID-19. The mechanisms underlying the effects of COVID-19 on the brain are not fully known. Emerging evidence vis-à-vis pathogenesis and etiologies of COVID-19 brain effects is promising and may pave the way for future research and development of interventions.

Clozapine Therapy and COVID-19: A Systematic Review of the Prevalence Rates, Health Outcomes, Hematological Markers, and Patient Perspectives

BACKGROUND/OBJECTIVES

There have been concerns that clozapine treatment may undermine the capacity of the body to fight infection and increase the vulnerability to contracting COVID-19. This review of recent cohort studies investigated (1) whether people with a severe psychiatric disorder are at increased risk of COVID-19 and complications, (2) the immunological response of clozapine-users who contract COVID-19, and (3) patients' perspectives on COVID-19 and the pandemic response.

METHODS

A systematic search of EMBASE, Medline, Pubmed, and PsycINFO databases using PRISMA guidelines using "COVID-19", "clozapine", and "vaccination" terms.

RESULTS

18 studies (out of 330 identified) met all criteria (N = 119 054 including 8045 on clozapine). There was no strong evidence that clozapine users may be at increased risk of contracting COVID-19 or developing complications after adjusting for medical comorbidities. Hematological studies showed temporary reductions in neutrophils in COVID-19-positive patients and vaccination suggesting a clozapine effect in defence against infection. Vaccination studies did not report major adverse effects. Increased plasma levels of clozapine and neutropenia however point to COVID-19-related interference of clozapine metabolism. Patient surveys reported limited impact on mental health and positive attitudes regarding pandemic response.

CONCLUSION

This review did not find compelling evidence that the immune system of clozapine users put them at risk of COVID-19 and further complications. Evidence of drug-infection interactions however points to the importance of adhering to consensus guidelines about clozapine therapy during the pandemic. More evidence using longitudinal designs is required to examine the longer-term effects of COVID-19 and vaccination in this vulnerable population.

Neutropenia in Patients With Clozapine-Treated Schizophrenia: An Effect of Clozapine or a Consequence of SARS-CoV-2 Infection? A Systematic Review

BACKGROUND

Clozapine is the only approved antipsychotic for treatment-resistant schizophrenia. Despite its therapeutic benefits, it is still widely underused, mainly because of its potential to cause agranulocytosis and neutropenia. Prescribing clozapine in COVID-19-positive patients became more challenging because of this potential side effect. This article is a review of literature on the risk of neutropenia associated with clozapine treatment in patients with COVID-19.

AREAS OF UNCERTAINTY

In clozapine-treated COVID-19-positive patients, neutropenia was reported in some cases; is it a consequence of clozapine treatment or of SARS-Co2 infection?

DATA SOURCES

Data were extracted from 2 databases: PubMed/MEDLINE and Google Scholar. We selected all original reports, from March 2020 until May 2022, on neutropenia associated with clozapine treatment in positive COVID-19 patients. Eleven studies were selected for the final analysis.

THERAPEUTIC ADVANCES

Before the COVID-19 pandemic, neutropenia in clozapine-treated patients was reported in 3.8% of cases. During the pandemic, neutropenia rates seemed to be higher. As per the cause of neutropenia, studies reported contradictory results. We aim to clarify rates and causes of neutropenia in clozapine-treated COVID-19-positive patients.

RESULTS

Three hundred eighty-eight articles were initially selected from the 2 databases. After excluding duplicates, unrelated articles, reviews, and guidelines, 11 studies were analyzed, all centered on clozapine treatment, COVID-19 infection, and associated neutropenia.

CONCLUSIONS

Clozapine treatment in COVID-19-positive patients may be associated with a transient reduction of absolute neutrophils count, in some cases reaching neutropenia levels. Neutropenia rates reported in SARS-CoV-2-infected patients are higher than the prepandemic reports; therefore, we assume that the cause might be a result of the immunological interference between clozapine and SARS-CoV-2. Clozapine treatment needs to be continued whenever possible, with dose adjustments in relation to blood test results.

Neutropenia after the coadministration of clozapine and nirmatrelvir-ritonavir in a patient with SARS-CoV-2 infection: A case report with a literature review

BACKGROUND

Schizophrenia is considered one of the major risk factors for mortality from SARS-CoV-2 infection. Early antiviral treatment is important to decrease the risk of mortality. Currently, Paxlovid (nirmatrelvir-ritonavir) has been widely used in SARS-CoV-2 patients with risk factors. However, drug-drug interactions with anti-psychotics are prominent and complicated.

CASE PRESENTATION

We report a clozapine-treated patient with SARS-CoV-2 infection who developed neutropenia after coadministration with Paxlovid. In this case, clozapine was used for over 15 years, without neutropenia development. However, severe neutropenia (absolute neutrophil count = 523/μl) developed 3 days after the coadministration of Paxlovid 2 doses per day, valproic acid 1,000 mg per day and clozapine 100 mg per day. The development of neutropenia may be attributed to the complicated interaction among Paxlovid, SARS-CoV-2 infection, valproic acid, fluvoxamine and clozapine.

CONCLUSIONS

Neutropenia is a rare but life-threatening event if a concomitant infection occurs. The risk may increase during SARS-CoV-2 infection and the coadministration of clozapine and Paxlovid. Although the exact causes of neutropenia in this patient are not fully clear, the white blood cell count and absolute neutrophil count should be closely monitored during the administration of Paxlovid in clozapine-treated patients with SARS-CoV-2 infection.

Clozapine and Neutropenia in Patients with Schizophrenia and SARS-CoV-2 Infection

BACKGROUND

Clozapine (CLZ) is used for treatment-resistant schizophrenia (TRS). Adverse reactions to clozapine include neutropenia. In March 2020, WHO declared the COVID-19 pandemic and after, psychiatrists raised concerns regarding continuation of clozapine, due to multiple restrictions. We aimed to provide a study on the association between neutropenia and clozapine in patients with schizophrenia and COVID-19.

AIM

To assess the neutrophil count in patients with schizophrenia treated with clozapine and infected with COVID-19.

METHODS

The study patients with schizophrenia, according to DSM-5, admitted to the Clinical Hospital of Psychiatry and Neurology Brasov, Romania, between April 2020 and October 2021. The inclusion criteria included positive RT-PCR (real-time PCR) test for COVID-19 and treatment with clozapine. We assessed three values of ANC (absolute neutrophil count): before COVID-19 infection (last ANC obtained at mandatory check), during infection and 1 month after resolution (first negative PCR test).

RESULTS

Of the 105 cases, 95 did not have neutropenia. Fifty-nine patients were males (62.1%), mean age was 43.5 years (SD = 12.1) with an average of clozapine treatment of 52.4 months (SD = 11.9). At baseline, they had a small reduction in the ANC mean value (4.41 × 109/l; SD = 2.22) which did not constitute a statistically significant decline from the prior to COVID-19 mean value of 4.66 × 109/l (SD = 2.34; p = 0.45). Values were also normal in the first month after negative PCR testing (4.45 × 109/l; SD = 2.35; p = 0.91). A total of 10 patients (9.5%) had neutropenia. The age, dose of clozapine and duration of treatment were not statistically different compared to the group without neutropenia.

CONCLUSION

Psychiatrists and other health professionals should keep in mind that neutrophil count may decrease during COVID-19 infection in patients taking clozapine and in some cases, neutropenia may even occur. We assumed that neutropenia could be caused by COVID-19 and clozapine interaction.

Clozapine treatment and risk of severe COVID-19 infection

OBJECTIVE

To investigate whether patients with clozapine treatment are at an increased risk of a more severe COVID-19 infection as compared with patients on other antipsychotic drugs.

METHODS

In this register-based cohort study, all residents (age 18 or older) in the Stockholm Region with a psychotic disorder diagnosis and antipsychotic treatment were included (N = 8 233) and followed from 1 March 2020 to 14 January 2021. The exposure was defined as clozapine treatment and the outcome measures (indicating a more severe COVID-19 infection) were: inpatient care, care within intensive care unit or death due to COVID-19 infection. Differences in outcome rates between exposed (n = 966) and unexposed (other antipsychotics; n = 7 267) were examined using Cox proportional hazards models and expressed as hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

No statistically significant differences in outcome rates were found between the two groups of patients after adjusting for age, sex and residence in retirement homes. The adjusted HR for the exposed compared to the unexposed was 0.96 (95% CI: 0.54, 1.70) for inpatient care; 1.69 (0.48, 5.93) for care in intensive care unit (ICU); and 0.86 (0.26, 2.80) for death. Regarding inpatient care, additional adjusting for country of birth, living in socioeconomically vulnerable areas, number of care visits during the previous year, and comorbid medical illnesses did not alter the results.

CONCLUSIONS

Our results may add support to the present guidelines, recommending sustained clozapine treatment during the current COVID-19 pandemic with careful monitoring and readiness to alter drug doses as needed.

Psychotropics and COVID-19: An analysis of safety and prophylaxis

The use of psychotropics during the COVID-19 pandemic has raised two questions, in order of importance: first, what changes should be made to pharmacological treatments prescribed to mental health patients? Secondly, are there any positive side effects of these substances against SARS-CoV-2? Our aim was to analyze usage safety of psychotropics during COVID-19; therefore, herein, we have studied: (i) the risk of symptomatic complications of COVID-19 associated with the use of these drugs, notably central nervous system activity depression, QTc interval enlargement and infectious and thromboembolic complications; (ii) the risk of mistaking the iatrogenic impact of psychotropics with COVID-19 symptoms, causing diagnostic error. Moreover, we provided a summary of the different information available today for these risks, categorized by mental health disorder, for the following: schizophrenia, bipolar disorder, anxiety disorder, ADHD, sleep disorders and suicidal risk. The matter of psychoactive substance use during the pandemic is also analyzed in this paper, and guideline websites and publications for psychotropic treatments in the context of COVID-19 are referenced during the text, so that changes on those guidelines and eventual interaction between psychotropics and COVID-19 treatment medication can be reported and studied. Finally, we also provide a literature review of the latest known antiviral properties of psychotropics against SARS-CoV-2 as complementary information.

Clozapine and COVID-19: A Case Report and Clinical Considerations

BACKGROUND

The emergence of coronavirus SARS-CoV-2, and the subsequent global epidemic of COVID-19, brought with it innumerable new clinical experiences across all medical specialties, and psychiatry is no exception. Individuals with serious mental illness, in particular schizophrenia and related disorders, may be especially susceptible to coronavirus infection given the overlapping risk factors of vulnerable sociodemographic status, increased challenges with quarantining requirements, and limited compliance with "respiratory etiquette." The case presented here describes a patient with schizophrenia who was being managed on clozapine and who developed symptomatic COVID-19 infection. Special care was taken to ensure that potential interactions between clozapine and the associated COVID-19 treatments were safe for the patient's mental and physical wellbeing.

CASE PRESENTATION

A 71-year-old schizophrenic Caucasian male is being managed with clozapine. While hospitalized, the patient was screened positive for COVID-19 and was admitted to the ICU due to his declining respiratory status. He was treated with both remdesivir and prednisone. He was able to fully recover from his COVID-19 infection.

CONCLUSION

The authors review the clinical characteristics of the case, highlighting both the overlapping synergistic effects and antagonistic influences of clozapine therapy in combination with COVID-19 and its associated treatments. A review of the literature offers an opportunity to examine various frameworks for individualized clinical decision-making while making the case for greater epidemiologic research into the optimal management of individuals with a psychotic disorder who are diagnosed with COVID-19 infection.

Reduction in Absolute Neutrophil Counts in Patient on Clozapine Infected with COVID-19

Despite its severe adverse effects, such as agranulocytosis, clozapine is the primary treatment for treatment-resistant schizophrenia. The established clozapine monitoring system has contributed to reducing agranulocytosis incidence and mortality rates. However, the pandemic coronavirus disease 2019 (COVID-19) has caused changes in the monitoring system. This review aimed to assess the current evidence on the neutrophil changes in the patient on clozapine treatment and infected with COVID-19. Individual cases reported various absolute neutrophil count (ANC) levels, normal, reduced, or elevated. No agranulocytosis case was reported. One case had a borderline moderate-severe ANC level, but the patient was in the 18-week period of clozapine treatment. A cumulative analysis of case the series initially reported inconclusive results. However, a more recent study with a larger sample size reported a significant reduction in the ANC during COVID-19 infection. Nevertheless, this effect is transient as no significant difference was found between the baseline and the post-infection period in ANC levels. In conclusion, COVID-19 is associated with a temporary reduction in ANC levels. The results supported the recommendation to reduce the frequency of clozapine monitoring in the eligible candidates. However, more data are required to confirm the current findings given the limitations, including study design, sample size, and statistical analysis.

COVID-19: Risks, Complications, and Monitoring in Patients on Clozapine

The Dutch Clozapine Collaboration Group is frequently asked for advice about the management of clozapine-treated patients when infected with or vaccinated against SARS-CoV-2. We provide state of the art information about the risks of SARS-CoV-2 infection for patients on clozapine and we give advice on measures to be taken, especially in regard to the monitoring of clozapine plasma levels, WBC count and differentiation during COVID-19 and after vaccination. We present an overview of relevant editorials, observational studies, and case studies, in which COVID-19 was reported in patients on clozapine. Patients using clozapine may have a higher risk of infection than patients with schizophrenia spectrum disorders (SSD) using other antipsychotics. SARS-CoV-2 infection can result in a dangerous increase of clozapine plasma levels, and granulocytopenia and lymphocytopenia (generally mild and short-term) may also occur, usually not as a result of clozapine treatment. Clozapine intoxication, pneumonia and delirium are the main complications of COVID-19 in patients on clozapine. In order to prevent clozapine intoxication, reduction of the original dose by half is generally recommended in clozapine users who contract COVID-19. When a cytokine storm is suspected in an advanced stage of COVID-19, reduction by three quarters seems more appropriate. If COVID-19 patients on clozapine develop granulocytopenia, SARS-CoV-2, rather than clozapine, should be considered as the cause. Schizophrenia patients in general and clozapine users in particular belong to a high-risk group that warrants early vaccination on a medical indication.

Schizophrenia during the COVID-19 pandemic

PURPOSE OF REVIEW

The coronavirus disease 19 (COVID-19) pandemic is having a critical impact on healthcare systems across the world, as well as on mental health in the general population; however, evidence regarding the impact of the COVID-19 pandemic on people living with schizophrenia and on the onset of psychotic symptoms is currently emerging.

RECENT FINDINGS

People living with schizophrenia are at an increased risk of COVID-19 and present worse COVID-19-related outcomes, including mortality. They show low levels of information and of concern regarding the possibility of contagion and infection but presented substantially stable levels of psychotic symptoms and even increased subjective well being during the pandemic. SARS-CoV-2, as well as the prolonged social isolation and the spread of misinformation, appear to be responsible in some cases for the onset of psychotic symptoms.

SUMMARY

Clinicians should inform and educate their patients on the risks related to SARS-CoV-2 infection and COVID-19 and on the precautions that they should adopt to avoid contagion. Particular attention should be devoted to maintaining the continuity of care, especially in frail patients. Telemedicine might represent a valid support, but face-to-face visits in some cases remain essential. The hypothesis of a direct role of viral infection on the onset of psychotic disorders is currently debated, as viral involvement of central nervous system appears to be rather infrequent in COVID-19.

Clozapine, neutropenia and Covid-19: should clinicians be concerned? 3 months report

BACKGROUND

Clozapine is among the most effective antipsychotics used for treatment resistant schizophrenia. Adverse reactions to clozapine include neutropenia. In March 2020, at the start of the Coronavirus -19 pandemic, clinicians raised concerns regarding continuation of antipsychotic treatment, and specifically of clozapine, in patients with coronavirus disease. We aimed here at providing a short report focusing on the association between neutropenia and clozapine in a case series of psychiatric inpatients diagnosed with COVID-19.

PATIENTS & METHODS

We retrospectively inspected data of 10 patients on clozapine, admitted to Highgate Mental Health Centre, Camden & Islington NHS Foundation Trust, between March and July 2020; selection was based on their COVID-19 positive PCR test. We used a linear regression model to estimate whether there was a significant drop in the neutrophil count during SARS-CoV-2 infection.The analysis was done in R using a linear regression to the origin.

RESULTS

Data were collected on 10 patients, of which 7 were males. During COVID-19 infection, neutrophils' count (ANC) was 4.13 ​× ​109/l (SD ​= ​2.70) which constituted a significant drop from a baseline value of 5.2 ​× ​109/l (SD ​= ​2.24). The mean relative reduction in ANC was -0.2729 (SD ​= ​0.1666). The beta value of 0.8377 obtained with the linear regression showed that ANC values during SARS-CoV-2 infection were 83.77% of the baseline ANC showing that within the two time points there was a decrease of 16.23%. The linear regression had a pvalue ​= ​8.96 ​× ​10-8 and an adjusted R2 of 95.94% which shows that the variability of the data is very well explained by the model. We also compared baseline ANC with ANC values approximately a month after resolution of the infection and results indicate that ANC values return to a 95% of baseline.

CONCLUSIONS

Clinicians should bear in mind that a significant drop in neutrophils' count may occur in patients taking clozapine and affected from a SARS-CoV-2 infectionand that this drop is only transitory.

COVID-19 infection causes a reduction in neutrophil counts in patients taking clozapine

BACKGROUND

Monitoring of white cell counts during clozapine treatment leads to cessation of therapy if levels fall below predetermined values. Reductions in white cell counts, driven by lower levels of lymphocytes, have been observed with coronavirus disease 2019 (COVID-19). Neutropenia during COVID-19 has not been reported. We present data for 56 patients who were taking clozapine and had COVID-19.

METHODS

We included patients who were taking clozapine at the time they tested positive for COVID-19. We compared absolute neutrophil counts, lymphocyte counts and white cell counts between baseline and the first week of infection, and baseline and the second week of infection.

RESULTS

We observed reductions in absolute neutrophil counts (p = 0.005), lymphocyte counts (p = 0.003) and white cell counts (p < 0.001) between baseline and the first 7 days of COVID-19. All cell counts had returned to baseline levels by days 8 to 14. Six patients experienced neutropenia (absolute neutrophil counts < 2.0 × 109/L) and of those, 4 underwent mandatory cessation of clozapine. For 3 patients, clozapine treatment had been established for more than 6 months with no previous neutropenia, neutrophil levels returned to baseline within 2 weeks and no further neutropenia was observed on restarting treatment.

LIMITATIONS

This was a retrospective chart review; larger cohorts are required. Clozapine plasma levels were largely not measured by clinicians.

CONCLUSION

These data strongly suggest that mild neutropenia in the acute phase of COVID-19 in patients who are well established on clozapine is more likely to be a consequence of the virus than of clozapine treatment.

Suspected Recurrence of Symptomatic COVID-19: Management During Inpatient Psychiatric Treatment

The widespread prevalence of coronavirus disease 2019 (COVID-19) means that inpatient psychiatric units will necessarily manage patients who have COVID-19 that is comorbid with acute psychiatric symptoms. We report a case of recurrence of respiratory symptoms and positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription-polymerase chain reaction (RT-PCR) testing in a patient on an inpatient psychiatric unit occurring 42 days after the initial positive SARS-CoV-2 RT-PCR test, 38 days after initial symptom resolution, and 30 days after the first of 3 negative SARS-CoV-2 RT-PCR tests. Over the course of the admission, the patient was safely initiated on clozapine. Recent literature on COVID-19's potential recurrence and neuropsychiatric effects is reviewed and implications for the management of COVID-19 on inpatient psychiatric units are discussed. In the era of COVID-19 and our still-developing understanding of this illness, psychiatrists' role as advocates and collaborators in our patients' physical health care has become even more critical.

Toxicity of psychotropic drugs in patients with COVID-19: A systematic review

OBJECTIVE

Due to the global spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), guidance for the use of psychotropic drugs in this context is necessary. We aimed to review clinical evidence regarding the potential toxicity of psychiatric medications in the context of SARS-CoV-2 infection.

METHODS

A systematic search for all types of empirical studies and reviews in a broad set of electronic databases and trial registries was conducted up to the 15th of August 2020.

RESULTS

We identified 3 case series and 4 single-case reports on the occurrence of toxicity induced by various psychotropic drugs (lithium, n = 2; clozapine, n = 5; risperidone n = 2; haloperidol n = 1; duloxetine, n = 1). In addition, we provide a new case report on the possible precipitation of valproic acid-induced hyperammonemic encephalopathy. In most cases, SARS-CoV-2 infection may have precipitated drug toxicity/side effects. The management of toxicity did not diverge from the usually applied principles in the absence of infection.

CONCLUSIONS

Due to the limited available evidence and the recent genomic diversity and evolution of the SARS-CoV-2, it is currently not possible to derive evidence-based recommendations for the use of psychotropic drugs in the context of SARS-CoV-2 infection. Nevertheless, we provide some guidance based on the reviewed literature. At the current state of knowledge, there is no contraindication for any psychotropic drug. Caution is warranted regarding the dosing and, in particular, the monitoring of clozapine, lithium and valproate.