Myobloc（rimabotulinumtoxin B） Important Safety Information Distant Spread of Toxin Effect Postmarketing reports indicate that the effects of MYOBLOC and all botulinum toxin products may spread from the area of injection to produce symptoms consistent with botulinum toxin effects. These may include asthenia, generalized muscle weakness, diplopia, blurred vision, ptosis, dysphagia, dysphonia, dysarthria, urinary incontinence, and breathing difficulties. These symptoms have been reported hours to weeks after injection. Swallowing and breathing difficulties can be life threatening and there have been reports of death. The risk of symptoms is probably greatest in children treated for spasticity but symptoms can also occur in adults treated for spasticity and other conditions, particularly in those patients who have underlying conditions that would predispose them to these symptoms. In unapproved uses, including spasticity in children and adults, and in approved indications, cases of spread of effect have occurred at doses comparable to those used to treat cervical dystonia and at lower doses. (See WARNINGS, PRECAUTIONS, and OVERDOSE sections of full Prescribing Information). MYOBLOC® (rimabotulinumtoxinB) Injection is indicated for the treatment of adults with cervical dystonia to reduce the severity of abnormal head position and neck pain associated with cervical dystonia. Units of biological activity of MYOBLOC cannot be compared to or converted into units of any other botulinum toxin products. Before administering MYOBLOC, physicians should consult the full Prescribing Information and Medication Guide. The most frequently reported adverse events with MYOBLOC are dry mouth, dysphagia, dyspepsia, and injection site pain. The vast majority of these adverse events were mild to moderate, temporary, self-resolving, and more common with higher doses. These adverse events may occur within the first week following treatment and may have a duration of several months. In controlled clinical trials, few patients (<1%) stopped treatment due to dry mouth or dysphagia. There is a reduced frequency of dry mouth and dysphagia reported with continued treatment. Dysphagia has commonly been reported by patients treated with all botulinum toxins for cervical dystonia. Caution should be exercised when administering MYOBLOC to individuals with motor neuron disease (e.g., amyotrophic lateral sclerosis), peripheral motor neuropathic diseases (e.g., motor neuropathy) or neuromuscular junctional disorders (e.g., myasthenia gravis or Lambert-Eaton syndrome). These patients may be at increased risk of clinically significant systemic effects including severe dysphagia and respiratory compromise from typical doses of MYOBLOC. In these patients, rare cases of dysphagia severe enough to cause aspiration pneumonia or to warrant the insertion of a gastric feeding tube have also been reported. Coadministration of MYOBLOC and aminoglycosides or other agents interfering with neuromuscular transmission (e.g., curare-like compounds) should only be performed with caution as the effect of the toxin may be potentiated. 部份中文B型肉毒毒素处方资料（仅供参考） Elan公司的B型肉毒杆菌毒素产品 Myobloc美国获准用于颈肌张力障碍（痉挛性斜颈）的对症治疗。是在美国获准用于这一适应证的第一个药物，属罕见药。 颈肌张力障碍是累及颈和肩部肌肉的痛苦病症，是肌肉不随意收缩引起的。阻断了神经与受累肌肉之间的胆碱能传导，使被治的肌肉松弛。公司说，将以“即时用”（ready－to－use）配方供应，不需重新配制，每瓶剂量有三种规格；2500、 5000及10000单位，使给药有最大灵性活。 药理作用 本品经由3步过程抑制神经肌肉接点处乙酰胆碱释放：重链介导的毒素与神经特异性结合；经受体介导的细胞内吞作用使毒素内在化；轻链移位至神经细胞溶质，作为锌依赖性内部蛋白酶分解神经递质释放所必需的多肽，此为三磷酸腺苷(ATP)和酸碱度(pH)依赖性。已证实本品特异性地分解突触囊泡相关膜蛋白，此蛋白是担负使突触囊泡与突触前膜对接并融合(神经递质释放必不可少的步骤)的蛋白复合物成分之一。 药动学 未进行药动学或吸收、分布、代谢与排泄研究，但预期给予推荐剂量肌注后，在周围血液中本品的水平无法测得。 适应证 本品适用于颈张力障碍的治疗，减轻与颈张力障碍有关的头部位置异常和颈痛。 禁忌证 对本品成分过敏者禁用。 注意事项 1.周围运动神经性疾病(如肌萎缩性脊髓侧索硬化，运动神经病)或神经肌肉接点疾病(如重症肌无力或Lambert Eaton综合征)患者慎用。 本品生殖毒性分级为C，孕妇慎用。尚不知本品是否经乳汁分泌，哺乳期妇女慎用。 2.不同血清型的肉毒素合用或交叉给药可能增加神经肌肉麻痹危险。 3.本品可用生理盐水稀释，溶液应在4h内使用。 4.药物过量以后，应对患者全身无力或麻痹的临床症状监测数周。发生药物过量，可用抗毒素解救，但抗毒素不能改善已经出现的全身无力症状。 5.儿童用药安全性尚未评价。 6.2～8℃冰箱保存，防止冷冻，不得振摇。 不良反应 临床研究中最常见的不良反应有口干、吞咽困难、消化不良和注射部位疼痛。口干和吞咽困难是治疗中止的最常见原因。吞咽困难的发生率随注入胸锁乳突肌剂量的增加而升高。 口干的发生率随注入头夹肌、斜方肌和胸锁乳突肌的剂量呈相关性升高。 1.全身：过敏反应、发热、头痛、胸痛、背痛、肌无力、无力、意外伤害、寒战、疝气、不适、脓肿、囊肿、赘生物、病毒感染、流感样综合征。 2.骨骼肌肉系统：关节炎、关节病。 3.心血管系统：偏头痛。 4.呼吸系统：呼吸困难、肺病、肺炎、咳嗽加重。 5.神经系统：焦虑、震颤、感觉过敏、嗜睡、意识错乱、疼痛、眩晕、头晕、血管扩张。 6.消化系统：消化不良、吞咽困难、口干、恶心、胃肠道疾病、呕吐、舌炎、口炎、牙病。 7.皮肤：瘙痒。 8.泌尿生殖系统：尿路感染、膀胱炎、阴道念珠菌病。 9.特异感觉：弱视、中耳炎、视觉异常、味觉颠倒、耳鸣。 10.代谢及营养疾病：周围水肿、水肿、高胆固醇血症。 11.血液淋巴系统：淤斑。 12.其他：注射部位疼痛。 用法用量 肌注，对于曾对肉毒素注射剂耐受的患者，推荐首剂用量为2500～5000U。先前无耐受史患者，首剂应使用较低剂量，随后根据患者的个体反应调整剂量。 药物相应作用 氨基糖苷类或其他干扰神经肌肉传递的药物(如箭毒类化合物)可能增强本品的作用。