Five Month-Persistent Extrapyramidal Symptoms following a Single Injection of Paliperidone Palmitate: A Case Report

Risk of Drug-induced Movement Disorders with Newer Antipsychotic Agents

Background:

The last decade has seen development of numerous novel antipsychotic drugs with unique mechanisms including long-acting formulations for clinical use. A comparative assessment of these new drugs with each other and previous antipsychotics have not been performed with regards to risk for drug-induced movement disorders (DIMD).

Methods:

Medline was searched from January 2010 to February 2022 for primary research articles and review articles in English using the search terms “extrapyramidal” and “tardive” with individual drug names of novel antipsychotics.

Results:

We identified articles describing the risk of DIMD with 6 novel antipsychotics, 4 novel formulations, and 3 experimental antipsychotics. Both short- and long-term data generally showed comparable to lower risk of DIMD with novel antipsychotics and recent long-acting formulations compared to previously marketed antipsychotics.

Discussion:

Several novel antipsychotics, particularly lumateperone and pimavanserin, show promise in being able to treat psychosis while reducing the risk of DIMD. Long-acting paliperidone may reduce risk of DIMD while other long-acting injectable formulations of SGA have similar risk of DIMD compared to oral formulations. New drug targets for treating psychosis without dopamine blockade also show promise.

How Loading Dose Strategies for Depot Paliperidone Can Go Wrong

This column presents a real-life case of a patient who developed severe and prolonged Parkinsonism secondary to the loading dose strategy recommended in the prescribing information (package insert) for paliperidone palmitate (Invega Sustenna). This column presents 2 major points. First, the case illustrates what the practitioner must do before following the general guidelines for a loading dose approach to the administration of paliperidone palmitate as outlined in the package insert to decrease the likelihood of a serious and potentially fatal consequence. Second, the case illustrates how therapeutic drug monitoring can be useful in assessing and managing patients who develop an untoward reaction. In this case, therapeutic drug monitoring was done using serum prolactin levels because the available laboratory could not measure the level of the drug itself in plasma, and the case highlights some limitations to keep in mind when using plasma prolactin levels to do such monitoring. To put this case in context, a review of the literature was conducted which identified 3 related cases. The author also refers readers to previous articles on therapeutic drug monitoring and pharmacokinetic considerations that arise when using depot (long-acting injectable) antipsychotics.

Therapeutic Drug Monitoring of Long-Acting Injectable Antipsychotic Drugs

BACKGROUND

The use of therapeutic drug monitoring (TDM) to guide treatment with long-acting injectable (LAI) antipsychotics, which are increasingly prescribed, remains a matter of debate. The aim of this review was to provide a practical framework for the integration of TDM when switching from an oral formulation to the LAI counterpart, and in maintenance treatment.

METHODS

The authors critically reviewed 3 types of data: (1) positron emission tomography data evaluating dopamine (D2/D3) receptor occupancy related to antipsychotic concentrations in serum or plasma; D2/D3 receptors are embraced as target sites in the brain for antipsychotic efficacy and tolerability, (2) pharmacokinetic studies evaluating the switch from oral to LAI antipsychotics, and (3) pharmacokinetic data for LAI formulations. Based on these data, indications for TDM and therapeutic reference ranges were considered for LAI antipsychotics.

RESULTS

Antipsychotic concentrations in blood exhibited interindividual variability not only under oral but also under LAI formulations because these concentrations are affected by demographic characteristics such as age and sex, genetic peculiarities, and clinical variables, including comedications and comorbidities. Reported data combined with positron emission tomography evidence indicated a trend toward lower concentrations under LAI administration than under oral medications. However, the available evidence is insufficient to recommend LAI-specific therapeutic reference ranges.

CONCLUSIONS

Although TDM evidence for newer LAI formulations is limited, this review suggests the use of TDM when switching an antipsychotic from oral to its LAI formulation. The application of TDM practice is more accurate for dose selection than the use of dose equivalents as it accounts more precisely for individual characteristics.

Paliperidone palmitate-induced facial angioedema: A case report

BACKGROUND

Paliperidone palmitate is a once-monthly injectable, atypical antipsychotic. To our knowledge, there has been only one report of paliperidone palmitate-induced angioedema presenting with acute laryngeal edema with subsequent respiratory arrest. Here, we present a case report of paliperidone palmitate-induced angioedema with a relatively mild clinical presentation compared with the previously reported case, and the patient’s condition was not complicated by life-threatening anaphylaxis.

CASE SUMMARY

A 79-year-old female, who had a major neurocognitive disorder due to Alzheimer’s disease with behavioral disturbances. Paliperidone palmitate was off-label used to control her aggression, irritability, and psychosis. After induction doses (150 mg and 100 mg intramuscularly, given 1 wk apart), she developed intermittent swelling of the face, eyelids, and lips on day 17 after the initial dose, and the edema was explicitly seen on day 20. The diagnosis was paliperidone palmitate-induced angioedema. The monthly injection dose was discontinued on day 33 after the initial dose. The angioedema was subsequently alleviated, and it had completely resolved by day 40 after the initial dose.

CONCLUSION

Paliperidone palmitate-induced angioedema is a rare condition and can present with a mild, intermittent facial edema, which may be overlooked in clinical practice.

Accidental Overdose of Paliperidone Palmitate

Long-acting injectable (LAI) antipsychotics first introduced in 1960s are useful in the treatment of schizophrenic patients with poor medication adherence due to their maintaining feature of therapeutic plasma level without daily administration. Paliperidone Palmitate is one of such LAI antipsychotic drugs used due to its benefit of maintaining a therapeutic plasma level with four-week interval of injections. We report the case of a 21-year-old male with a history of mental illness that presented with selective mutism, disorganized speech, thought process and behavior, and auditory hallucinations who accidentally received 624 mg Paliperidone Palmitate intramuscularly with no reported side effects after 2 weeks of monitoring and observation. Paliperidone is a D2, 5HT2A receptor antagonist with additional antagonist activity at α-1 and α-2, H-1 receptor sites, and four metabolic pathways identified for its metabolism. Studies have reported adverse effects such as acute dystonia, acute renal failure, and cardiovascular abnormalities with Paliperidone overdose; however there is no reported literature on Paliperidone Palmitate overdose, though there have been reported cases of Paliperidone Palmitate side effects of hypersexuality and angioedema with the standard dose.

Long-lasting extrapyramidal symptoms after multiple injections of paliperidone palmitate to treat schizophrenia

PURPOSE

Antipsychotic drug treatment can potentially lead to adverse events such as extrapyramidal symptoms (EPSs). If these events persist, they lower patient quality of life. The purpose of this report is to present our experience with such a case, as an example to encourage further study.

PATIENTS AND METHODS

The patient was a 64-year-old male who had been diagnosed with schizophrenia that had been treated with oral antipsychotics for over 40 years. Due to lack of compliance, he was treated with the long-acting injectable antipsychotic, paliperidone palmitate, but developed persistent EPSs after 6 months. He was subsequently treated and monitored in our inpatient facility.

RESULTS

Antipsychotic treatment was stopped. After 6 weeks, the patient's psychosis had worsened, but his EPSs remained unchanged. Levodopa treatment was then started (up to 400 mg/d), which improved his EPSs, so he was restarted on oral antipsychotic therapy (aripiprazole, 6-18 mg/d). His psychotic symptoms improved over 2 months. The improvements in both psychosis and EPSs remained stable. Dopamine transporter scans revealed moderate dopamine transporter loss in the striatum, and computed tomography revealed no sign of brain abnormalities, suggesting that the patient was susceptible to dopamine reductions.

CONCLUSION

Paliperidone palmitate can induce EPSs, even if injected only a few times. Although the characteristics of the drug are potential causes, the patient's predisposition to dopamine perturbations can also influence the outcome. Therefore, adequate awareness is required before injection.