An Epidemiological Study of Concomitant Use of Chinese Medicine and Antipsychotics in Schizophrenic Patients: Implication for Herb-Drug Interaction

Abstract

BackgroundHerb-drug interactions are an important issue in drug safety and clinical practice. The aim of this epidemiological study was to characterize associations of clinical outcomes with concomitant herbal and antipsychotic use in patients with schizophrenia.Methods and FindingsIn this retrospective, cross-sectional study, 1795 patients with schizophrenia who were randomly selected from 17 psychiatric hospitals in China were interviewed face-to-face using a structured questionnaire. Association analyses were conducted to examine correlates between Chinese medicine (CM) use and demographic, clinical variables, antipsychotic medication mode, and clinical outcomes. The prevalence of concomitant CM and antipsychotic treatment was 36.4% [95% confidence interval (95% CI) 34.2%–38.6%]. Patients using concomitant CM had a significantly greater chance of improved outcomes than non-CM use (61.1% vs. 34.3%, OR = 3.44, 95% CI 2.80–4.24). However, a small but significant number of patients treated concomitantly with CM had a greater risk of developing worse outcomes (7.2% vs. 4.4%, OR = 2.06, 95% CI 2.06–4.83). Significant predictors for concomitant CM treatment-associated outcomes were residence in urban areas, paranoid psychosis, and exceeding 3 months of CM use. Herbal medicine regimens containing Radix Bupleuri, Fructus Gardenia, Fructus Schisandrae, Radix Rehmanniae, Akebia Caulis, and Semen Plantaginis in concomitant use with quetiapine, clozapine, and olanzepine were associated with nearly 60% of the risk of adverse outcomes.ConclusionsConcomitant herbal and antipsychotic treatment could produce either beneficial or adverse clinical effects in schizophrenic population. Potential herb-drug pharmacokinetic interactions need to be further evaluated.

Peony-Glycyrrhiza Decoction, an Herbal Preparation, Inhibits Clozapine Metabolism via Cytochrome P450s, but Not Flavin-Containing Monooxygenase in In Vitro Models

“…Our epidemiological study has shown that CLZ is often concomitantly used with herbal medicine, which may result in adverse clinical outcomes (Zhang et al, 2011).…”

“…With an increasing use of herbal medicine in managing psychiatric disease, herb-drug interactions have become an important issue in clinical practice (Zhang et al, 2010(Zhang et al, , 2011. This is particularly apparent in China where herbal medicine has become an important therapeutic approach to psychiatric disorders (Zhang et al, 2010).…”

“…This is particularly apparent in China where herbal medicine has become an important therapeutic approach to psychiatric disorders (Zhang et al, 2010). Our recent epidemiological study has found that approximately 37% of schizophrenic patients sought herbal medicine treatment while they were under antipsychotic medication (Zhang et al, 2011). However, supplementary use of herbal medicine can result in both beneficial and adverse clinical outcomes (Peterson et al, 2008;Przekop and Lee, 2009;DMD # 62653 5 of 27 Zhang et al, 2011).…”

“…Our recent epidemiological study has found that approximately 37% of schizophrenic patients sought herbal medicine treatment while they were under antipsychotic medication (Zhang et al, 2011). However, supplementary use of herbal medicine can result in both beneficial and adverse clinical outcomes (Peterson et al, 2008;Przekop and Lee, 2009;DMD # 62653 5 of 27 Zhang et al, 2011). Therefore, identifying potential interactions between herbal and antipsychotic agents is critical for promoting drug safety in clinical psychiatry.…”

Unwanted Interactions Among Psychotropic Drugs and Other Treatments for Autism Spectrum Disorders

“…However, it was reported that 33.4% of patients using antipsychotics also took traditional Chinese medicine concurrently; 7.2% of these patients had worse outcomes compared to 4.4% of those using antipsychotics alone. 45 Risperidone is metabolized and can contribute to numerous drug interactions because it is metabolized by CYP3A4, the most common drug-metabolizing enzyme. 46 Many children have GI problems 47 and are given numerous medications that change the GI flora.…”