ABSTRACT
Yokukansan, one of the traditional Japanese herbal medicines, ameliorated neuropathic pain symptoms in patients. In this study, we investigated the effects of yokukansan on neuropathic pain in chronic constriction injury (CCI) model. Oral administration of yokukansan significantly inhibited mechanical and cold allodynia in the von Frey hair or acetone test, respectively. In comparison, amitriptyline, a tricyclic antidepressant, demonstrated moderate, but not significant, antiallodynic effects in the mechanical and cold tests. Yokukansan significantly inhibited the cerebrospinal fluid dialysate level of glutamate that had increased by the stimulation of brush or acetone. Glutamate transporter inhibitors, DL-threo-beta-hydroxy aspartate and dihydrokainate, decreased the yokukansan-induced antiallodynic actions in CCI rats. Our results suggest that yokukansan was confirmed to have antiallodynic effects in CCI rats, which are related to a blockade of glutamatergic neurotransmission via activation of glutamate transporters in the spinal cord.
ABSTRACT
A 74-year-old man was admitted to our hospital complaining of severe neck pain and general fatigue. He had been undergoing treatment for post-operative neck pain at the out-patient clinic of our hospital, but was now complaining of pain more intense than usual. Chest X-rays revealed diffuse ground glass shadows in bilateral lung fields, and computed tomography revealed diffuse intestinal shadows. A drug lymphocyte stimulation test (DLST) was also performed at that time. Steroid pulse therapy improved the clinical symptoms, hypoxemia and chest X-ray findings. DLST performed again with Yokukansan and Hachimijiogan 133 days after the initial diagnosis of pneumonitis showed Yokukansan was positive. This result showed Yukukansan may be a causative drug for allergic drug-induced pneumonitis. Any drugs including kanpo may be possible to induce allergic pneumonitis.
Subject(s)
Alveolitis, Extrinsic Allergic/etiology , Drugs, Chinese Herbal/adverse effects , Aged , Alveolitis, Extrinsic Allergic/diagnosis , Alveolitis, Extrinsic Allergic/drug therapy , Humans , Lymphocyte Activation , Male , Methylprednisolone/administration & dosage , Pulse Therapy, Drug , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
BACKGROUND: Neuropathic pain that is the chronic, severe, and intractable pain, interferes with activities of daily living (ADL) and consequently reduces quality of life (QOL). We reported the efficacy of Yokukansan in patients with neuropathic pain, including acute herpetic pain, postherpetic neuralgia, central poststroke pain, post-traumatic spinal cord injury pain, thalamic syndrome, complex regional pain syndrome and symptomatic trigeminal neuralgia. Yokukansan was more effective compared with traditional medicines, such as tricyclic antidepressants, carbamazepine, gabapentin, and opioids etc., which are recommended to treat neuropathic pain. Recently, effects of Yokukansan is reported on the behavioral and psychological symptoms of dementia (BPSD) in elderly patients with dementia. Repeated administration of Yokukansan decreases expression of 5-hydroxytryptamine (5-HT) 2A receptors in the prefrontal cortex in mice, and Yokukansan also protects destruction of myelin sheaths in rats with thiamine deficient-induced encephalopathy. Mechanism of effectiveness of Yokukansan on neuropathic pain has not been established; however, efficacy of Yokukansan on neuropathic pain has been shown clinically. CONCLUSIONS: As far as we know, this is the first report that Yokukansan was effective on neuropathic pain. Yokukansan without serious adverse reactions may be a possible medicine for treatment of neuropathic pain in future.
Subject(s)
Drugs, Chinese Herbal/therapeutic use , Neuralgia/drug therapy , Phytotherapy , Adult , Aged , Aged, 80 and over , Animals , Chronic Disease , Drugs, Chinese Herbal/pharmacology , Female , Humans , Male , Mice , Middle Aged , Myelin Sheath/pathology , Prefrontal Cortex/metabolism , Rats , Receptor, Serotonin, 5-HT2A/metabolism , Thiamine Deficiency/pathologyABSTRACT
Yokuininto was effective in treating burning pain in both lower legs of a 58-year-old woman. She felt her lower legs feverish: however, no neurological deficit or abnormal finding in angiography was found. The burning pain was increased by cold and decreased by warm, but was alleviated by epidural block with local anesthetics. After 2-week medication of Yokuininto, burning pain was reduced to 20 to 30% and fever in legs disappeared. Yokuininto has been used for chronic pain in muscle and joint accompanied by swelling or local fever. This patient had no joint pain or swelling, but her burning pain was considered to have resulted from some abnormality in blood circulation due to disorder in discharge of water in the body.