XENAZINE®: 25 mg, scored tablets (INN: tetrabenazine) Xenazine® is indicated for the treatment of Huntington’s chorea. GENERIC NAME: Tetrabenazine BRAND NAME: Xenazine How does it work? Xenazine (Tetrabenazine) works by depleting the stores of certain chemicals called neurotransmitters within nerve cells in the brain. These neurotransmitters include dopamine, serotonin and noradrenaline and are normally involved with the passage of messages between nerve cells in the brain and the normal functioning of the brain and nervous system. Depleting the brain of these neurotransmitters can help control movement disorders caused by diseases of the brain and nervous system, although the exact mechanism of action is not fully understood. Xenazine (Tetrabenazine) is mainly used to control movement disorders associated with diseases of the brain and nervous system, such as Huntington's chorea, but can also be used to control movement disorders caused by antipsychotic medicines. The older antipsychotic medicines such as chlorpromazine, haloperidol and flupentixol can cause side effects involving involuntary movement of the tongue, face, mouth and jaw, which may sometimes be accompanied by involuntary movements of the arms and legs (tardive dyskinesia). If this is disabling or socially embarrasing, and persists despite stopping or reducing the dose of the antipsychotic, the symptoms can be treated using tetrabenazine. Xenazine (Tetrabenazine) can also be used if it is not possible to stop or change the antipsychotic. What is it used for? Movement disorders associated with disease of the brain and spinal cord Nerve cell breakdown resulting in irregular involuntary movements and brain disease (Huntington's chorea) Rhythmical involuntary movement of the tongue, face, mouth and jaw, which may sometimes be accompanied by involuntary movements of the arms and legs (tardive dyskinesia) Warning! Do not drink alcohol whilst taking this medicine. This medicine may cause drowsiness. If affected do not drive or operate machinery. Not to be used in: No known conditions This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately. Pregnancy and Breastfeeding: Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine. There is no information about the safety of this medicine during pregnancy, but it has been widely used for many years without apparent ill consequence. As there is no safety information available, the manufacturer does not recommend the use of this medicine when breastfeeding. Alternatively, if this medicine must be used, the mother should not breastfeed. Seek medical advice from your doctor. Label warnings: This medication may cause drowsiness. If affected do not drive or operate machinery. Avoid alcoholic drink. Side effects: Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect. Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain Low blood pressure (hypotension) High temperature combined with falling levels of consciousness, paleness, sweating and a fast heart beat (neuroleptic malignant syndrome). Requires stopping the medicine and immediate medical treatment. The side effects listed above may not include all of the side effects reported by the drug's manufacturer. For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist. How can this medicine affect other medicines? Xenazine (Tetrabenazine) should not be taken at the same time as, or for 14 days following a course of monoamine oxidase inhibitor (MAOI) antidepressants, as this can cause restlessness, disorientation and confusion. Xenazine (Tetrabenazine) opposes the effects of levodopa. Xenazine (Tetrabenazine) should not be taken with alcohol as this may increase the drowsiness experienced. FDA 批准了首个用于治疗亨廷顿舞蹈症的药物 美国食品与药品管理局 (FDA) 最近批准了Xenazine (丁苯那嗪) 用于治疗亨廷顿病 (Huntington’s disease) 的舞蹈症。舞蹈症是发生在患有这种疾病的人身上的不自主的抽动症状。 Xenazine 是美国 FDA 批准的可用于治疗亨廷顿病的首个药物。目前尚没有其它药物获得 FDA 批准用于治疗舞蹈症。服用 Xenazine 可能带来的严重副作用包括抑郁症和自杀倾向。因此 Xenazine 不能用于有自杀倾向的人或者没有得到治疗的抑郁症病人。 Xenazine 能够减少脑部多巴胺的量。多巴胺是一种用于神经细胞间进行信息传递的化学物质。在亨廷顿病人身上，这种信息传递过度活跃并导致身体异常运动，称为舞蹈症。Xenazine 通过减少多巴胺的量来达到减少身体不自主运动的疗效。 这种药物可以在短期内改善舞蹈症，但研究人员在临床试验中也发现，它可能会引起病人在情绪、认知、稳定性以及个体能力的恶化。因此病人在服用该药物时，医生以及病人家属需要留心病人在各个方面的表现和可能出现的副作用。