Yokukansan
Encyclopedia
Yokukansan Yi-Gan San (in China) or 抑肝散 is a traditional Asian herbal medicine. It was originally described in 保嬰撮要 (Bâo yïng cuö yào, Synopsis for Protecting Infant) written by 薛鎧(Xue Kai) and 薛己 (Xue ji, a son of Xue Kai) in Ming dynasty China 1555 or 1556 as a remedy for restlessness and agitation
in children. Yokukansan (YKS) contains a mixture of dried herb
s, 4 g of Atractylodis lanceae rhizoma (蒼朮), 4 g of Poria (伏苓), 3 g of Cnidii
rhizoma (川芎), 3 g of Angelicae radix (当帰), 2 g of Bupleuri radix (柴胡), 1.5 g of Glycyrrhizae radix (甘草), and 3 g of Uncariae uncis cum ramulus (釣藤鈎). These herbs are registered in the Pharmacopoeia of Japan ver. 15. Patients take 2.5 g of YKS powder (1.08 g extract) three times a day. YKS has been approved by the Ministry of Health, Labour and Welfare (Japan)
as prescriptions covered under the National Health Insurance plan.
(BPSD). Since then, many studies showing the effects and mechanisms of YKS on psychosomatic and neurological symptoms have been published as below. Iwasaki et al. reported a 15 dementia with Lewy bodies (DLB) patient case series where hallucinations and other BPSDs were successfully improved with YKS treatment. Mizukami et al. (2009) reported their expanded crossover trial of the effects of YKS on BPSD.
Shinno et al.reported that YKS was effective for control of psychiatric symptoms and improvement of sleep structure in patients with BPSD. Miyaoka et al. reported that YKS successfully treated neuroleptic-induced tardive dyskinesia and borderline personality disorder. Satoh et al. have also recently reported that YKS improved involuntary movements in Huntington’s disease. These clinical reports suggest that YKS has an antipsychotic
like effect without causing extrapyramidal symptoms
.
. Takeda et al. (2008) pointed out that YKS attenuated abnormal glutamate release in rats on a diet deficient in zinc. They also reported that YKS significantly suppressed the increase in extracellular concentrations of glutamate and aspartate seen in the hippocampus
of zinc-deficient rats after stimulation with KCl. Egashira et al. (2008) reported that YKS inhibited the 2,5-dimethoxy-4-iodoamphetamine-induced head-twitch response and decreased expression of 5-hydroxytryptamine 2A receptors in the prefrontal cortex. Also, Terawaki K et al. reported partial agonistic effect of YKS on human recombinant serotonin 1A receptors expressed in the membranes of Chinese hamster ovary cells. These reports suggest involvement of serotonergic and glutamatergic functions is the underlying mechanisms of YKS. Though Tabuchi et al. reported that YKS ameliorated cognitive disturbances in APP transgenic mice (animal model of AD), the improvement of cognition with YKS was not clinically demonstrated. Shimada et al. (2001) reported that an aqueous extract of the hooks and stems of Uncaria sinensis (Oliv.) Havil., Uncariae uncus cum ramulus, a herb in YKS, protected against glutamate-induced neuronal death in cultured cerebellar granule cells. They suggested that oxyindole alkaloids such as isorhynchophylline, isocorynoxeine and rhynchophylline and indole alkaloids such as hirsuteine and hirsutine were the active components of the Uncariae. These compounds may cause the clinical effects of YKS.
Psychomotor agitation
Psychomotor agitation is a series of unintentional and purposeless motions that stem from mental tension and anxiety of an individual. This includes pacing around a room, wringing one's hands, pulling off clothing and putting it back on and other similar actions...
in children. Yokukansan (YKS) contains a mixture of dried herb
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...
s, 4 g of Atractylodis lanceae rhizoma (蒼朮), 4 g of Poria (伏苓), 3 g of Cnidii
Kampo herb list
Kampō medicine is the Japanese study and adaptation of Traditional Chinese medicine. In 1967, the Japanese Ministry of Health, Labour and Welfare approved 4 kampo medicines for reimbursement under the National Health Insurance program. In 1976, 82 kampo medicines were approved by the Ministry...
rhizoma (川芎), 3 g of Angelicae radix (当帰), 2 g of Bupleuri radix (柴胡), 1.5 g of Glycyrrhizae radix (甘草), and 3 g of Uncariae uncis cum ramulus (釣藤鈎). These herbs are registered in the Pharmacopoeia of Japan ver. 15. Patients take 2.5 g of YKS powder (1.08 g extract) three times a day. YKS has been approved by the Ministry of Health, Labour and Welfare (Japan)
Ministry of Health, Labour and Welfare (Japan)
The ' is a cabinet level ministry of the Japanese government. It is commonly known as Kōrō-shō in Japan. This ministry provides regulations on maximum residue limits for agricultural chemicals in foods, basic food and drug regulations, standards for foods, food additives, etc.It was formed with...
as prescriptions covered under the National Health Insurance plan.
Clinical evidence
In 2005, Iwasaki et al. (Japan) reported that YKS improved Behavioral and psychological symptoms such as hallucination, delusion, agitation and aggression in dementiaDementia
Dementia is a serious loss of cognitive ability in a previously unimpaired person, beyond what might be expected from normal aging...
(BPSD). Since then, many studies showing the effects and mechanisms of YKS on psychosomatic and neurological symptoms have been published as below. Iwasaki et al. reported a 15 dementia with Lewy bodies (DLB) patient case series where hallucinations and other BPSDs were successfully improved with YKS treatment. Mizukami et al. (2009) reported their expanded crossover trial of the effects of YKS on BPSD.
Shinno et al.reported that YKS was effective for control of psychiatric symptoms and improvement of sleep structure in patients with BPSD. Miyaoka et al. reported that YKS successfully treated neuroleptic-induced tardive dyskinesia and borderline personality disorder. Satoh et al. have also recently reported that YKS improved involuntary movements in Huntington’s disease. These clinical reports suggest that YKS has an antipsychotic
Antipsychotic
An antipsychotic is a tranquilizing psychiatric medication primarily used to manage psychosis , particularly in schizophrenia and bipolar disorder. A first generation of antipsychotics, known as typical antipsychotics, was discovered in the 1950s...
like effect without causing extrapyramidal symptoms
Extrapyramidal symptoms
The extrapyramidal system can be affected in a number of ways, which are revealed in a range of extrapyramidal symptoms , also known as extrapyramidal side-effects , such as akinesia and akathisia .Extrapyramidal symptoms are various movement disorders such as acute dystonic reactions,...
.
Pharmacological mechanisms
Sekiguchi et al. (2009) demonstrated that administration of YKS ameliorated aggressive behavior in A beta injected mice. Also, they demonstrated that YKS did not suppress motor activity, nor did it induce catalepsyCatalepsy
Catalepsy is also a term used by hypnotists to refer to the state of making a hypnotised subject's arm, leg or back rigid. "Arm catalepsy" is often a pre-hypnotic test performed prior to an induction into a full trance.-Causes:...
. Takeda et al. (2008) pointed out that YKS attenuated abnormal glutamate release in rats on a diet deficient in zinc. They also reported that YKS significantly suppressed the increase in extracellular concentrations of glutamate and aspartate seen in the hippocampus
Hippocampus
The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
of zinc-deficient rats after stimulation with KCl. Egashira et al. (2008) reported that YKS inhibited the 2,5-dimethoxy-4-iodoamphetamine-induced head-twitch response and decreased expression of 5-hydroxytryptamine 2A receptors in the prefrontal cortex. Also, Terawaki K et al. reported partial agonistic effect of YKS on human recombinant serotonin 1A receptors expressed in the membranes of Chinese hamster ovary cells. These reports suggest involvement of serotonergic and glutamatergic functions is the underlying mechanisms of YKS. Though Tabuchi et al. reported that YKS ameliorated cognitive disturbances in APP transgenic mice (animal model of AD), the improvement of cognition with YKS was not clinically demonstrated. Shimada et al. (2001) reported that an aqueous extract of the hooks and stems of Uncaria sinensis (Oliv.) Havil., Uncariae uncus cum ramulus, a herb in YKS, protected against glutamate-induced neuronal death in cultured cerebellar granule cells. They suggested that oxyindole alkaloids such as isorhynchophylline, isocorynoxeine and rhynchophylline and indole alkaloids such as hirsuteine and hirsutine were the active components of the Uncariae. These compounds may cause the clinical effects of YKS.