Research and Interests
1) Antipsychotic Polypharmacy:
Antipsychotic polypharmacy is the practice of prescribing more than one antipsychotic to a given patient at the same time. Current clinical practice guidelines do not support this practice and states that antipsychotic polypharmacy should be the last strategy employed to treat patients with schizophrenia. Despite this lack of endorsement, the practice of antipsychotic polypharmacy continues to increase. Our research group continues to study the prevalence, predictors, indicators and clinical outcomes associated with this practice.
2) The Influence of Serum Lipids on the Clozapine’s Clinical Efficacy:
In some cases, changes in plasma lipoproteins can modify the pharmacokinetics, tissue distribution, and pharmacological activity of lipophilic compounds such as clozapine. The fact that clozapine therapy, in many cases, can elevate serum lipids compelled our group to further examine what effect, if any, this dyslipidemia could have on clozapine’s serum distribution, kinetics, and clinical response. Our research findings have shown a significant positive correlation between serum triglycerides and clinical response to clozapine. We are now exploring possible mechanism(s) that underlie this finding.
3) Smoking and Schizophrenia:
With a prevalence as high as 90%, individuals with schizophrenia not only consume more nicotine than the general population but also more than individuals with other psychiatric diagnoses. Our research group has investigated: 1) the relationship between tobacco consumption and antipsychotic treatment (in terms of chlorpromazine equivalents and anticholinergic load, 2) self-reported motivations to smoke, and 3) predictors of starting to smoke in first episode patients.
4) The Pharmacoeconomics of Schizophrenia:
As a consequence of its prevalence, early onset and chronicity, schizophrenia imposes clinical and economic impediments to healthcare practitioners. Among the armamentarium of agents available to treat the symptoms of this devastating illness, the atypical antipsychotics have received the most attention. Although these agents have proven valuable, their use has often been limited by their high acquisition costs relative to the older conventional antipsychotics. Our research on the pharmacoeconomics of the atypical antipsychotics has been successful in raising the awareness to healthcare practitioners and decision-makers alike of the challenges of providing quality care while balancing fiscal responsibility.
5) Clinical Trials in Schizophrenia:
Our group continues to carry out trials of antipsychotics examining their effectiveness, safety and tolerability. We have just recently completed a trial that examined whether long-acting injectable risperidone is effective in reducing psychotic symptoms in treatment refractory patients.
6) Metabolic Effects of Antipsychotics:
The therapeutic use of atypical antipsychotics is associated with a high incidence of metabolic side effects. Using a rodent model, our group is currently investigating the acute and chronic effects of the atypical antipsychotics on alterations in glucose and insulin parameters with the goal of determining the mechanism(s) that underlie this phenomenon.
- Procyshyn RM, Honer WG, Wu TKY, Ko RWY, McIsaac SA, Young AH, Johnson JL, Barr AM. Persistent antipsychotic polypharmacy and excessive dosing in the community psychiatric treatment setting. Journal of Clinical Psychiatry 2010;71:566-573.
- Procyshyn RM, Barr AM, Brickell T, Honer WG. Medication errors in Psychiatry: A comprehensive review. CNS Drugs 2010;24:595-609.
- Okoli CTC, Khara M, Procyshyn RM, Johnson JL, Barr A, Greaves L. Smoking cessation interventions among individuals in methadone maintenance: A brief review. Journal of Substance Abuse, 2010;38:191-199.
- Barr AM, Procyshyn RM, Hui P, Johnson J, Honer WG. Self-reported motivation to smoke in schizophrenia is related to antipsychotic drug treatment. Schizophrenia Research 2008;100:252-260.
- Procyshyn RM, Wasan K, Thornton AE, Barr AM, Chen EYH, Stip E, Williams R, MacEwan GW, Birmingham CL, Honer WG. Changes in Serum Lipids, Independent of weight, are associated with changes in symptoms during long-term clozapine treatment. Journal of Psychiatry and Neuroscience 2007;32:331-338.
- Rosland M, Szeto P, Procyshyn RM, Barr AM. Wasan KM. Determination of clozapine and its metabolite, norclozapine in various biological matrices using high-performance liquid chromatography. Drug Development and Industrial Pharmacy 2007;33:1158-1166.
- Dumontet J, Malyuk R, Kiang G, Procyshyn RM. Corrected QTc intervals in newly admitted geriatric psychiatric patients: An examination of risk factors. Canadian Journal of Psychiatry 2006;51(6):371-376.