Yi-Gan San as Adjunctive Therapy for Treatment-Resistant Schizophrenia: An Open-Label Study
ABSTRACT Recent studies indicate that the traditional Japanese herbal medicine yi-gan san (YGS; yokukan-san in Japanese) may be safe and useful in treating behavioral and psychological symptoms in patients with dementia and borderline personality disorder. We aimed at evaluating both the efficacy and safety of YGS in patients with treatment-resistant schizophrenia.
Thirty-four patients diagnosed with schizophrenia according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, (YGS-free) group (n = 25) and treated in a 4-week open-label study with YGS at an average daily dosage of 6.7 +/- 2.5 g (range, 2.5-7.5 g). Psychometric instruments used to assess efficacy included the Positive and Negative Syndrome Scale for Schizophrenia and the Drug-Induced Extrapyramidal Symptom Scale.
A significant decrease was observed at 2 weeks and at 4 weeks in each Positive and Negative Syndrome Scale for Schizophrenia subscale score in the YGS group, but this was not observed in the control group. However, the Drug-Induced Extrapyramidal Symptom Scale total score did not change in both groups.
In this open-label pilot study, patients treated with YGS showed a statistically significant reduction on clinician-rated scales. The present findings suggest that an adjunction of YGS might be effective for treatment-resistant schizophrenia.
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ABSTRACT: Japanese traditional herbal medicine (Kampo) has its origins in traditional Chinese medicine (TCM). It was introduced to Japan in the middle of the sixth century and has evolved over the past 1,400 years after combining with Japan's original folk remedies. While it retains some similarities to TCM, Kampo has evolved in Japan, resulting in a system of medicine that has many differences from TCM. Kampo medicine is considered to be very safe; in Japan, Kampo herbal formulas are manufactured by licensed pharmaceutical companies, prescribed by Western-trained medical doctors (usually as a freeze-dried extract), and have quality control standards similar to those of prescription drugs. The present study examined Yokukan-san (Yi-Gan San in TCM), a Kampo formula that has been used empirically in Japan for more than 400 years. Accumulating clinical trials have demonstrated Yokukan-san's efficacy in treating patients with behavioral and psychological symptoms of dementia, which has resulted in the Japanese Society of Neurology listing it in the Japanese Guidelines for the Management of Dementia 2010. Efficacy in other diseases and conditions, such as sleep disorders, tardive dyskinesia, aggression, and impulsivity has also been reported. This article reviews both clinical and basic studies of Yokukan-san, with the goal of clarifying its clinical indications.Neuropsychiatric Disease and Treatment 09/2014; 10:1727-42. DOI:10.2147/NDT.S65257 · 2.15 Impact Factor
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ABSTRACT: Neurodevelopmental impairment in the serotonergic system may be involved in autism spectrum disorder. Yokukansan is a traditional herbal remedy for restlessness and agitation in children, and mother-infant co-administration (MICA) to both the child and the nursing mother is one of the recommended treatment approaches. Recent studies have revealed the neuropharmacological properties of Yokukansan (YKS), including its 5-HT1A (serotonin) receptor agonistic effects. We investigated the influence of YKS treatment on behavior in a novel environment and on brain monoamine metabolism during the nursing period in an animal model of neurodevelopmental disorders, prenatally BrdU (5-bromo-2'-deoxyuridine)-treated rats (BrdU-rats). YKS treatment did not influence locomotor activity in BrdU-rats but reduced grooming in open-field tests. YKS treatment without MICA disrupted the correlation between locomotor behaviors and rearing and altered levels of serotonin and its metabolite in the cerebellum. These effects were not observed in the group receiving YKS treatment with MICA. These data indicate a direct pharmacological effect of YKS on the development of grooming behavior and profound effects on cerebellar serotonin metabolism, which is thought to be influenced by nursing conditions.The Cerebellum 10/2014; 14(2). DOI:10.1007/s12311-014-0611-2 · 2.86 Impact Factor
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ABSTRACT: Schizophrenia is a debilitating psychotic mental disorder that affects almost the entire range of human mental function. The devastating effect of the illness is usually long-lasting and requires lifelong treatment. Despite an evolved psychopharmacological understanding, the overall therapeutic effect of antipsychotics is still not satisfactory. The choice of proper medication presents a clinical dilemma between efficacy and safety. As a result, searching for comparable treatment options with safer profiles is very important. Yokukansan (TJ-54), also called yi-gan san in Chinese, is a traditional herbal medicine with evident therapeutic effect for neuropsychiatric disorders. There are several open-label clinical studies upholding the possibility of using yokukansan to treat schizophrenia or schizophrenia-like psychosis. Evidence from animal studies and neurobiology also sheds light on the antipsychotic implications of yokukansan and its ingredients. Nevertheless, correlations between the experimental environment and clinical settings may be complicated by a number of confounders. Clinical trials with more sophisticated designs are required to fill the gap between the experimental environment and clinical settings.Neuropsychiatric Disease and Treatment 09/2014; 10:1629-34. DOI:10.2147/NDT.S67607 · 2.15 Impact Factor