英文药名: Xifaxan (Rifaximin Tablets)
中文药名: 利福昔明片

药品名称
通用名：利福昔明片
英文名：Rifaximin Tablets
成分：利福昔明。
化学名称：4-脱氧-4-甲基砒啶[1，2-1，2]咪唑井[5，4-环]利福霉素SV。
分子式：C13H51N13O11
分子量：785.89

药品介绍
美国食品药品管理局于2010年3月24日宣布，它已批准将Xifaxan(利福昔明) 用于晚期肝病患者，作为降低其显性肝性脑病(HE)复发风险的一种手段。Xifaxan之前曾被批准用于治疗旅行者腹泻。
一项随机安慰剂对照临床证实了Xifaxan用于预防HE的有效性，该试验的受试者由来自美国、加拿大和俄罗斯的成年肝病患者组成。Xifaxan在最严重肝病患者中的疗效未被研究。试验受试者从未或仅出现过轻微的HE症状。与接受安慰剂对照的受试者相比，接受Xifaxan治疗的患者在试验期间更少出现HE。然而，由于大部分患者在试验期间同时还在服用乳果糖，所以尚无法评估Xifaxan作为HE的一种独立疗法的疗效。
使用Xifaxan治疗肝病患者所报告的最常见不良反应包括外周性水肿、恶心、打嗝及头痛。
Salix公司表示美国FDA专家顾问委员会表示支持利福昔明（rifaximin，Xifaxan）550 mg片剂用于治疗慢性肝衰竭引起的神经系统损害，顾问委员会投过投票表示支持该药用于肝性脑病。肝衰竭患者的肝性脑病引起神经损害，导致患者出现昏迷与无意识症状。
本品已获得了用于此症的罕用药地位，将在美国获得7年的市场独占权。在Ⅲ期临床研究中，本品显著降低肝性脑病复发风险。肝性脑病常发生在肝硬化患者中，在美国有60万肝硬化患者。本品现在以商品名Xifaxan在美国销售用于由埃希氏菌属引起的旅行者腹泻。

药理作用
药理作用：利福昔明是广谱肠道抗生素。它是利福霉素SV的半合成衍生物。利福昔明和其它利福霉素类抗生素一样，通过与细菌DNA-依赖RNA聚合酶的B-亚单位不可逆转地结合而抑制细菌RNA的合成，最终抑制细菌蛋白质的合成。由于其与酶的结合是不可逆的，所以其活性为对敏感菌的杀菌活性。对利福昔明抗菌活性的研究资料显示，本品与利福霉素具有同样广泛的抗菌谱，对多数革兰氏阳性菌和革兰氏阴性菌，包括需氧菌和厌氧菌的感染具有杀菌作用。由于利福昔明口服时不被胃肠道吸收，所以它是通过杀灭肠道的病原体而在局部发挥抗菌作用。毒理作用：重复给药毒性：大鼠每天口服本品25,50及100mg/kg，连续180天后，耐受性好，除雌鼠血清总胆固醇呈剂量相关性增加外(可能为对肠道菌群产生作用的结果)，未见其他异常改变。遗传毒性：体内外研究未见本品有致突变作用。生殖毒性：大鼠及家兔给予本品50及100mg/kg未见致畸作用及其他生殖毒性。

药代动力学
在鼠，家狗和人体药代动力学的研究证明，本品经口服不被吸收(吸收小于1%)。

适应症
对利福昔明敏感的病原菌引起的肠道感染，包括急性和慢性肠道感染，腹泻综合症，夏季腹泻，旅行者腹泻和小肠结肠炎等。

用法用量
成人口服。每次0.2g(1片)，每日3-4次。
6-12岁儿童口服。每次0.1-0.2g(0.5-1片)，每日4次。
12岁以上儿童，剂量同成人。
可根据医嘱调节剂量和服用次数。除非是遵照医嘱的情况下，每一疗程不应超过7天。

不良反应
部分患者用药后可出现恶心（通常出现在第一次服药后），但症状可迅速消退。大剂量长期用药，极少数患者可能出现蕈麻疹样皮肤反应。
1，中枢神经系统有出现头痛的报道。
2，代谢/分泌系统肝性脑病患者服用本药后可出现体重下降，血清钾和血清钠浓度轻度升高。
3，胃肠道系统常见的症状为腹涨，腹痛，恶心和呕吐。以上症状发生率者均低于1%。
4，皮肤大剂量长期用药，极少数患者可能出现蕈麻疹样皮肤反应。
5，其他有用药后可能引起足水肿的报道。

禁忌
以下患者禁用：
1.对本药或利福霉素过敏者；
2.肠梗阻者；
3.严重的肠道溃疡性病变者。

注意事项
1.儿童连续服用本药不能超过7日。
2.对6岁以下儿童建议不要服用本药片剂。
3.长期大剂量用药或肠黏膜受损时，会有极少量（少于1%）被吸收，导致尿液呈粉红色。
4.请置于儿童触及不到的地方。
5.如果出现对抗生素不敏赶的微生物，应中断治疗并采取其他适当治疗措施。
6.对驾驶和操纵机器的影响，未知。

孕妇及哺乳期妇女用药
1.药物对妊娠的影响：动物实验本药无致畸作用。但妊娠期妇女用药的安全性和有效性尚不明确。因此，妊娠期妇女需权衡利弊后用药。
2.药物对哺乳的影响：本药口服后只有极少量被吸收，在乳汁中的浓度也极低，哺乳期妇女可在有适当医疗监测的情况下服用本药。

儿童用药
建议6岁以下儿童不要服用，6岁及6岁以上儿童服用方法请参见[用法用量]。

药物相互作用
口服利福昔明只有少于1%口服剂量经胃肠道吸收，所以利福昔明不会引起因药物的相互作用而导致的全身问题。

药物过量
试验证明服用本品剂量达1.6g/日，既没有局部也没有全身的不良事件发生。一旦过量服用应洗胃，并配合其他适当治疗。

【原产地英文商品名】XIFAXAN UNIT DOSE PACK 550mg/tab 60tabs/bottle
【原产地英文药品名】RIFAXIMIN
【中文参考商品译名】
注：以下产品是不同的规格和不同的价格，购买时请以电话咨询为准！
·XIFAXAN单位剂量包装 550毫克/片 60片/瓶
·XIFAXAN单位剂量包装 200毫克/片 100片/瓶
·XIFAXAN 550毫克/片 60片/瓶
·XIFAXAN 200毫克/片 100片/瓶
【生产厂家中文参考译名】SALIX PHARMS
【生产厂家英文名】SALIX PHARMS
【中文参考药品译名】利福昔明

Xifaxan
Generic Name: rifaximin (rif AX i min)
Brand Names: Xifaxan

What is Xifaxan?
Xifaxan (rifaximin) is an antibiotic that fights bacterial infection only in the intestines.

Xifaxan is used to treat travelers' diarrhea caused by E. coli in adults and children who are at least 12 years old. Most people get this infection by eating food or drinking fluids that have been contaminated with the bacteria.

Xifaxan is also used to lower the risk of worsened brain function, or hepatic encephalopathy, in adults with liver failure. Brain function can be affected when the liver stops working and cannot remove toxic substances from the body.

Xifaxan may also be used for other purposes not listed in this medication guide.

Important information about Xifaxan
You should not use take Xifaxan if you are allergic to rifaximin or medications such as rifabutin (Mycobutin), rifampin (Rifater, Rifadin, Rifamate), or rifapentine (Priftin).

Before you take Xifaxan, tell your doctor if you have severe liver disease, diarrhea with fever, or diarrhea that is watery or has blood in it.

Take Xifaxan for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Xifaxan will not treat a viral infection such as the common cold or flu, or any form of diarrhea that is caused by a virus. Call your doctor if your symptoms do not improve after 24 hours, or if they get worse while taking rifaximin. Xifaxan does not treat all bacterial forms of traveler's diarrhea.

Before taking Xifaxan
You should not use take Xifaxan if you are allergic to rifaximin or medications such as rifabutin (Mycobutin), rifampin (Rifater, Rifadin, Rifamate), or rifapentine (Priftin).

If you have any of these other conditions, you may need a Xifaxan dose adjustment or special tests:
severe liver disease;
diarrhea with a fever; or
watery or bloody diarrhea.

FDA pregnancy category C. It is not known whether Xifaxan will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using Xifaxan. It is not known whether rifaximin passes into breast milk or if it could harm a nursing baby. Do not use Xifaxan without telling your doctor if you are breast-feeding a baby.

How should I take Xifaxan?
Take Xifaxan exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Xifaxan can be taken with or without food.

Take this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Xifaxan will not treat a viral infection such as the common cold or flu, or any form of diarrhea that is caused by a virus. Call your doctor if your symptoms do not improve after 24 hours, or if they get worse while taking rifaximin. Xifaxan does not treat all bacterial forms of traveler's diarrhea.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid while taking Xifaxan?
Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, stop taking Xifaxan and call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Xifaxan side effects
Get emergency medical help if you have any of these signs of an allergic reaction to Xifaxan: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using Xifaxan and call your doctor at once if you have a fever or diarrhea that is watery or bloody.

Less serious Xifaxan side effects are more likely, and may include:
bloating, gas, stomach pain;
feeling like you need to empty your bowel urgently;
feeling like your bowel is not completely empty;
nausea, vomiting, constipation;
headache, dizziness;
tired feeling; or
swelling in your hands, feet, or torso.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Xifaxan?
There may be other drugs that can interact with Xifaxan. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?
Your pharmacist can provide more information about Xifaxan.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Xifaxan only for the indication prescribed.

Every effort has been made to ensure that the information provided is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects.