【通用名】埃索美拉唑镁　　

【英文名】Esomeprazole　Magnesium

【化学名称】双-S-5-甲氧基-2{[(4-甲氧基-3，5-二甲基2－吡啶基）甲基]亚磺酰基}-1H一苯并咪唑镁三水合物 　　
分子式：C34H36MgN6O6S2·3H2O 　　
分子量：767.15

【药理毒理】
对胃酸分泌的影响
口服埃索美拉唑20mg和40mg后，在一小时内起效。重复给以20mg每天一次连续5天，在第5天服药后6-7小时测量，五肽胃泌素刺激引起的平均高峰泌酸量降低90%。 　　
症状性GERD患者每天口服埃索美拉唑20mg和40mg，5天后24小时胃内PH＞4的阿间平均值分别为13小时和17小时。维持胃内PH＞4的时间至少8小时、12小时和16小时的患者比例在埃索美拉唑20mg时分别为76％、54％和24％；在40mg时分别为97％、92％和56％。在40mg时分别为97%、92%和56%。用AUC参数代替血浆药物浓度，可以显示胃酸分泌抑制与药物暴露之间的量-效关系。 　　
进食对埃索美拉唑降低胃内酸度的效应无显著影响。 　　
抑制胃酸的治疗效果 　　
反流性食管炎息者服用埃索美拉唑40mg4周的愈合率约为78％，8周后为93％． 　　
耐信(埃索美拉唑镁肠溶片)20mg一日二次与适当的抗菌药物联用治疗一周后，幽门螺杆菌的根除率约为90％。 　　
一周根除治疗后，对没有并发症的十二指肠溃疡患者无需再单用抑酸剂作愈合溃疡和消除症状的后续治疗。 　　
与抑制胃酸相关的其他效应 　　
使用抗酸药物治疗期间，酸分泌减少会导致血清胃泌素增高． 　　
在长期使用抗酸药物治疗期间，有报道胃腺囊肿的发生率有一定程度的增多．这些改变是显著地抑制泌酸后的生理性反应，其性匝为良性，并视为可逆性的．
临床前安全性资料
基于常规的多次用药毒性、基因毒性和生殖毒性研究临床前的相关研究没有显示埃索美拉唑对人类有特殊的危害。用消旋混合物在大鼠中的致癌研究发现了胃的ECL细胞增生和类癌、在大鼠中对胃的这些效应是由于持续、显著的高胃泌素血症的结果、后者继发于胃酸产生的减少见于长期使用胃酸分泌抑制剂后的大鼠。

【药代动力学】
吸收与分布
埃索美拉唑对酸不稳定，口服采用肠溶衣颗粒、体内转化为R-异构体的量可以忽略．埃索美拉唑吸收迅速，口服后约1－2小时血浆浓度达到高峰、单剂量40mg给药后的绝对生物利用度为64％，每日一次重复给药后的绝对生物利用度为89％、20mg剂量的相应值分别为50％和68％。健康受试者稳态时的表观分布容积约为0.22L/kg体重．埃索美拉唑的血浆蛋自结合率为97％。进食会延缓和降低埃索美拉唑的吸收，但对埃索美拉唑降低胃内酸度的效应无显著影响。
代谢与排泄
耐信(埃索美拉唑镁肠溶片)完全经细胞色素P450酶系统（CYP）代谢．埃索美拉唑的大部分代谢依靠多形性的CYP2C19，生成埃索美拉唑的羟化物和夫甲基代谢物。剩余部分依靠另一特殊异构体CYP3A4代谢生成埃索美拉唑砜，后者为血浆中的主要代谢物。以下的参数主要反映CYP2C19功能正常的个体即快代谢者的药代动力学特征。总血浆清除率在单次用药后约为17L/h， 多次用药后约为9L/h。血浆消除半衰期在重复每日一次用药后约为1.3小时。重复给药后，埃索美拉唑的血药浓度时间曲线下面积（AUC）增大．这种增大是剂量依赖性的井在多次用药后导致非线性的剂量AUC关系、这种时间和剂量依赖性是由于首过代谢和机体总清除系降低所致，造成这种降低的原因可能是埃索美拉唑和(或）其代谢物埃索美拉唑砜抑制了CYP2C19、按每日一次给药时，埃索美拉唑在两次用药期间从血浆中完主消除，没有累积的趋势。埃索美拉唑的主要代谢物对胃酸分泌无影响．一次口服剂量的近80％的埃索美拉唑以代谢物形式从尿中排泄，其余的从粪便中排出．尿中的原形药物不到1％。西方人群中大约1～2%的个体缺乏有活性的CYP2C19酶，称为慢代谢者；而在亚洲人群，慢代谢者在人群中所占的比例约为13－23％。这部分个体的埃索美拉唑代谢可能主要由CYP3A4催化。每日一次埃索美拉唑40mg重复给药后，慢代谢者的平均血药浓度-时间曲线下面积（AUC）比具有活性CYP2C19的个体（快代谢者）高出近100%，平均血浆峰浓度增加约60%。
特殊患者人群
埃索美拉唑在老年人(71～80岁)中的代谢没有显著性的变化。单剂给予埃索美拉唑40mg后，女性的血药浓度-时间曲线下面积的平均值要超过男性约30％。每日一次重复给药后未观察到性别的差异。这些发现与埃索美拉唑的剂量无关联。在有轻中度肝功能损害的患者中，埃索美拉唑的代谢会减弱。严重肝功能损害的患者代谢率降低，可使埃索美拉唑的血药浓度-时间曲线下面积(AUC)增大一倍。因此，严重肝功能损害的患者所使用的最大剂量不应超过20mg。每日用药一次时埃索美拉唑或其主要代谢产物没有累积的趋势。在肾功能减退的患者中还没有进行过类似的研究。由于肾脏只担负埃索美拉唑的代谢物而不是原形药物的排泄，因此肾功能损害的患者预期其埃索美拉唑的代谢不会发生变化.

【用法用量】药片应和液体一起整片吞服，而不应当阻嚼或压碎．对于存在吞咽困难的患者，可将片剂溶于半杯不含碳酸盐的水中（不应使用其他液体，因肠溶包衣可能被溶解）。搅拌，直至片剂完全崩解，立即或在30分钟内服用，再加入半杯水漂洗后饮用。微丸决不应被嚼碎或压破。对于不能吞咽的患者，可将片剂溶于不含碳酸盐的水中，并通过胃管给药。重要的是应仔细检查选择的注射器和胃管的合适程度。准备工作及使用指导如下：通过胃管给药： 1.将片剂放入合适的注射器，并加入约25ml水及5ml空气。有时需要50ml水，以防止管子被微丸堵塞。 2.立即振摇注射器约2分钟使片剂溶解。 3.使注射器尖端朝上，检查尖端未被堵塞。 4.将注射器插入管，并保持此位置。 5.振摇注射器，使尖端朝下。立即注射5-10ml入管。注射后翻转注射器并振摇。（注射器必须保持尖端朝上，以免尖端堵塞）。 6.使注射器尖端朝下，立即再向管中注射5-10ml，重复此步骤，直到注射器中无液体。 7.如需要洗下注射器剩余的残留物，重复步骤5，向注射器中加入25ml水及5ml空气，有时需要50ml水。胃食管反流性疾病（GERD）一糜烂性反流性食管炎的治疗 40mg每日一次 ，连服四周。对于食管炎未治愈或持续有症状的患者建议再服药治疗四周。一已经治愈的食管炎患者防止复发的长期维持治疗20mg每日一次。一胃食管反流性疾插旧ERD）的症状控制没有食管炎的患者20mg每日一次、如果用药4周症状未获控制，应对患者作进一步的检查。一旦症状消除，随后的症状控制可采用即时疗法即需要时口服20mg，每日一次。与适当的抗菌疗法联合用药根除幽门螺杆菌并且－愈合与幽门螺杆菌相关的十二指肠溃疡一预防与幽门螺杆菌相关的消化性溃疡复发埃索美拉唑镁肠溶片20 mg＋阿莫西林1g＋克拉霉素500 mg ，每日二次，共7天。

【适应症】
胃食管反流性疾病(GERD) 　　
－糜烂性反流性食管炎的治疗 　　
－已经治愈的食管炎患者防止复发的长期维持治疗 　　
－胃食管反流性疾病(GERD)的症状控制 　　
与适当的抗菌疗法联合用药根除幽门螺杆菌，并且 　　
－愈合与幽门螺杆菌感染相关的十二指肠溃疡 　　
－防止与幽门螺杆菌相关的消化性溃疡复发 　　

【不良反应】在埃索美拉唑的临床试验中已确定或怀疑有下列不良反应，这些反应均没有剂量相关性。常见反应(>1/100,<1/10) 头痛、腹痛、腹泻、腹胀、恶心/呕吐、便秘少见反应(>1/1000,<1/100) 皮炎、瘙痒、荨麻疹、头昏、口干罕见反应(>1/10000,<1/1000) 过敏性反应，如血管性水肿，过敏反应，肝 转氨酶升高在消旋体（奥美拉唑）的使用中曾观察到下列不良反应，因而在埃索美拉唑的使用中也可能发生。中枢和外周神经系统：感觉异常，嗜睡，失眠，眩晕。可逆性精神错乱，激动，易攻击，抑郁和幻觉，主要存在于严重疾病患者。内分泌：男子女性型乳房胃肠道：口腔炎和胃肠道念珠菌病血液学：白细胞减少症，血小板减少症，粒细胞缺乏症，全血细胞减少症。肝脏：肝转氨酶升高，脑病（先前有严重肝病者）；黄疸或非黄疸性肝炎；肝衰竭肌肉骨骼：关节痛，肌无力和肌痛。皮肤：皮疹，光过敏，多形性红斑，史蒂文斯-约翰逊综合征，中毒性上皮坏死，脱发。其他：不适。过敏反应，如：发热，支气管痉挛，间质性肾炎。多汗，外周水肿，视力模糊，味觉障碍和低钠血症 　　

【禁忌】已知对埃索美拉唑 、其它苯并咪唑类化合物或本品的任何其他成份过敏者。

【孕妇及哺乳期妇女用药】无妊娠期使用埃索美拉唑的临床资料可供参考。动物实验未显示埃索美拉唑对胚胎或胎儿发育有直接或间接的损害作用。用消旋混合物进行的动物实验未显示对妊娠、分娩或出生后发育有直接或间接的有害影响。但给妊娠期妇女使用埃索美拉唑应慎重。尚不清楚埃索美拉唑是否会经人乳排泄。也未在哺乳期妇女中进行过埃索美拉唑的研究，因此在哺乳期间不应使用埃索美拉唑镁肠溶片。 　　

【儿童用药】儿童不应使用埃索美拉唑，因没有相关的临床研究数据。 　　

【老年患者用药】老年患者无需调整剂量。

【药物相互作用】
1．埃索美拉唑对其他药物药代动力学的影响对于那些吸收过程受胃酸影响的药物，在埃索美拉唑治疗期间，由于胃酸下降，可增加或减少这些药物的吸收。与使用其他泌酸抑制剂或抗酸药一样，埃索美拉唑治疗期间酮康唑和依曲康唑的吸收会降低。埃索美拉唑抑制CYP2C19，后者为埃索美拉唑的主要代谢酶。因此，当埃索美拉唑与经CYP2C19代谢的药物(如地西泮、西酞普兰、丙米嗪、氯米帕明、苯妥英等)合用时，这些药物的血浆浓度可被升高，可能需要降低剂量。特别是埃索美拉唑用于按需治疗时，更应考虑这一点。合用埃索美拉唑30mg可使经CYP2C19代谢的地西泮的清除下降45％。合用埃索美拉唑40mg，可使癫痫患者的血浆苯妥英的谷浓度上升13％。因此，苯妥英治疗期间，当合用或停用埃索美拉唑时，建议监测苯妥英的血药浓度。有临床试验表明，接受华法林治疗的患者，合用埃索美拉唑40mg，凝血时间在可接受范围内。然而，上市后有报道，二者合用时，个别病例有临床显著性的国际标准化比率（INR）上升。因此，当开始合用或停用埃索美拉唑时，建议监测华法林的血药浓度。在健康志愿者中，合用埃索美拉唑40mg，可使西沙必利的血药浓度－时间曲线下面积(AUC)增加32％，消除半衰期(t1/2)延长31％，但并不显著性增高西沙必利的血浆峰浓度。合用埃索美拉唑不会加剧单用西沙必利所致的QTc间期的轻微延长作用。（见“注意事项”）。研究表明，埃索美拉唑对阿莫西林或奎尼丁的药代动力学没有临床相关性的影响。 　　
2．其他药物对埃索美拉唑药代动力学的影响埃索美拉唑经CYP2C19和CYP3A4代谢。埃索美拉唑与CYP3A4抑制剂克拉霉素(500mg每日二次)合用，可使机体对埃索美拉唑的血药浓度-时间曲线下面积(AUC)加倍，但埃索美拉唑的剂量无需调整。
3．配伍禁忌 无

【药物过量】
过量使用埃索美拉唑的经验非常有限，与280mg剂量相关的症状表现为胃肠道症状和无力。单剂量使用80mg埃索美拉唑无异常反应。没有已知的特异性解毒剂。埃索美拉唑广泛地与血浆蛋白质结合，因此难以透析。对任何过量中毒的治疗，应采用对症处理和全身支持疗法。

【原产地英文商品名】NEXIUM PACKET 10mg/packet 30packets/box
【原产地英文药品名】ESOMEPRAZOLE MAGNESIUM TRIHYDRATE
【中文参考商品译名】
注：以下产品不同的规格和不同的价格，购买时请以电话咨询为准！
·耐信袋装剂 20毫克/包 30包/盒
·耐信袋装剂 40毫克/包 30包/盒
·耐信袋装剂 10毫克/包 30包/盒
【中文参考药品译名】埃索美拉唑镁三水物
【生产厂家中文参考译名】阿斯利康
【生产厂家英文名】ASTRAZENECA

Nexium
Generic Name: esomeprazole (ee so MEP ra zol)
Brand Names: Nexium

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What is Nexium?
Nexium (esomeprazole) belongs to a group of drugs called proton pump inhibitors. Nexium decreases the amount of acid produced in the stomach.

Nexium is used to treat symptoms of gastroesophageal reflux disease (GERD) and other conditions involving excessive stomach acid such as Zollinger-Ellison syndrome. Nexium is also used to promote healing of erosive esophagitis (damage to your esophagus caused by stomach acid).

Nexium may also be given to prevent gastric ulcer caused by infection with helicobacter pylori (H. pylori), or by the use of nonsteroidal anti-inflammatory drugs (NSAIDs).

Nexium is not for immediate relief of heartburn symptoms.

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

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Important information about Nexium
You should not take Nexium if you are allergic to esomeprazole or to any other benzimidazole medication such as albendazole (Albenza), or mebendazole (Vermox).

If you have severe liver disease you may need an Nexium dose adjustment or special tests.

Nexium is not for immediate relief of heartburn symptoms.

Some conditions are treated with a combination of Nexium and antibiotics. Use all medications as directed by your doctor. Read the medication guide or patient instructions provided with each medication. Do not change your doses or medication schedule without your doctor's advice.

Take Nexium for the full prescribed length of time. Your symptoms may improve before the condition is fully treated.

Heartburn is often confused with the first symptoms of a heart attack. Seek emergency medical attention if you have chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, and a general ill feeling.

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Before taking Nexium
You should not take Nexium if you are allergic to esomeprazole or to any other benzimidazole medication such as albendazole (Albenza), or mebendazole (Vermox).

If you have severe liver disease you may need an Nexium dose adjustment or special tests.

Taking a proton pump inhibitor such as Nexium may increase your risk of bone fracture in the hip, wrist, or spine. This effect has occurred mostly in people who have taken the medication long term or at high doses, and in those who are age 50 and older. It is not clear whether Nexium is the actual cause of an increased risk of fracture. Before you take this medication, tell your doctor if you have osteoporosis or osteopenia (low bone mineral density).

Some conditions are treated with a combination of Nexium and antibiotics. Use all medications as directed by your doctor. Read the medication guide or patient instructions provided with each medication. Do not change your doses or medication schedule without your doctor's advice.

Heartburn is often confused with the first symptoms of a heart attack. Seek emergency medical attention if you have chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, and a general ill feeling.

FDA pregnancy category B. Nexium is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment with Nexium. It is not known whether esomeprazole passes into breast milk or if it could harm a nursing baby. Do not use Nexium without telling your doctor if you are breast-feeding a baby

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How should I take Nexium?
Take Nexium 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.

Nexium is usually given for 4 to 8 weeks only. Your doctor may recommend a second course of treatment if you need additional healing time.

Take each dose with a full glass (8 ounces) of water. Nexium should be taken at least one hour before a meal.

You may open the delayed-release capsule and sprinkle the medicine into a spoonful of pudding or applesauce to make swallowing easier. Swallow this mixture right away without chewing. Do not save the mixture for later use. Discard the empty capsule.

Nexium can be given through a nasogastric (NG) feeding tube. Open the capsule and sprinkle the medicine into a 60-milliliter syringe. Mix in 50 milliliters of water. Place the plunger into the syringe and shake the mixture well. Make sure there are no medicine granules stuck in the tip of the syringe. Attach the syringe to the NG tube and push the plunger down to empty the syringe into the tube. Then flush the tube with more water to wash the contents down.

Take Nexium for the full prescribed length of time. Your symptoms may improve before the condition is fully treated. Call your doctor if your symptoms do not improve or if they get worse while you are taking this medicine.

Store at room temperature away from moisture and heat.

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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.

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What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include confusion, headache, drowsiness, blurred vision, fast heartbeat, nausea, dry mouth, sweating, flushing, shortness of breath, tremor, loss of coordination, or seizure (convulsions).

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What should I avoid while taking Nexium?
Follow your doctor's instructions about any restrictions on food, beverages, or activity.

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Nexium side effects
Get emergency medical help if you have any of these signs of an allergic reaction to Nexium: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Less serious Nexium side effects may include:
headache, drowsiness;
diarrhea;
nausea, stomach pain, gas, constipation; or
dry mouth.

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.

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What other drugs will affect Nexium?
Nexium should not be taken together with atazanavir (Reyataz) or nelfinavir (Viracept). Tell your doctor if you are taking either of these medications to treat HIV or AIDS.

Tell your doctor about all other medicines you use, especially:
a blood thinner such as warfarin (Coumadin);
cilostazol (Pletal);
clopidogrel (Plavix);
digoxin (Lanoxin, Lanoxicaps);
diazepam (Valium);
ketoconazole (Extina, Ketozole, Nizoral, Xolegal);
saquinavir (Invirase); or
iron (Feosol, Mol-Iron, Fergon, Femiron, others).

This list is not complete and other drugs may interact with Nexium. 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.

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

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Nexium 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.