1　药理作用
甲吡唑用于乙二醇中毒的解救主要是通过抑制乙醇脱氢酶来实现的。乙二醇是抗冻剂和冷却剂中的主要成分，在体内乙醇脱氢酶的作用下会产生有毒的乙二醇代谢物(可能是乙二醛)。乙二醇急性中毒的临床表现有：中枢神经系统抑制、严重的代谢性酸中毒、肾功能衰竭和昏迷等。甲吡唑能够抑制乙醇脱氢酶的活性，从而有效地抑制了乙二醇代谢物的产生，最终达到治疗目的。

2　药动学特性
甲吡唑可供静注，蛋白结合率低，表观分布容积为0.8l.kg-1，半衰期为5h。其主要经肝脏代谢，可能与细胞色素P-450系统有关，消除过程与剂量大小有关，为非线性消除，无法用米氏方程来描述。本品主要经肾脏排泄，尿中的原型药物很少，主要是代谢产物4-carboxypyrazole，肾清除率为0.016ml.min-1.kg-1。
乙二醇中毒的早期患者，每12h静注400～1200mg，血药浓度可达到17～31μg.ml-1。中毒晚期进行透析的患者，给予负荷剂量20mg.kg-1，并持续静注(透析的同时)甲吡唑1.5mg.kg-1.h-1其血药浓度将高于14μg.ml-1。有研究表明治疗时的血药浓度应为8～15μg.ml-1或更高。

3　临床应用
3.1　乙二醇中毒　对于肾功能尚可的患者单独应用甲吡唑即有效，与乙醇治疗乙二醇中毒相比较，甲吡唑应用起来更方便、更安全。临床应用表明，及早应用甲吡唑(摄入乙二醇3～16h内)，1日2次(静注或口服)即可消除酸中毒而不需进行血液透析。对于伴随肾功能衰竭的患者应用甲吡唑的同时还应进行透析［1，3］。
3.2　乙醇过敏　通过抑制乙醇脱氢酶来减少乙醛的积累达到治疗目的。如果提前1h预防性的口服甲吡唑10mg.kg-1则能阻止过敏症状的出现［4］。
3.3　甲醇中毒　动物实验表明甲吡唑对甲醇中毒有效。

4　用法用量
本品供静脉注射，用生理盐水稀释。中毒早期肾功能良好者，首次静注800或1200mg，然后每12h静注减少用量如600mg，300mg或400mg，100mg或200mg，50mg或100mg，直到血中检测不到乙二醇或其浓度低于0.1g.L-1。肾功能衰竭的患者不必调整剂量。中毒晚期，出现无尿性肾功能衰竭的患者，应进行血液透析。血液透析对甲吡唑有明显的清除作用，故需要提高剂量。一般首次负荷剂量为10～20mg.kg-1，透析期间的组持剂量为1～1.5mg.kg-1vh-1。

5　不良反应及禁忌
最常见的不良反应是转氨酶的升高，其它的有眩晕、头疼、高甘油三酯血症、嗜酸性粒细胞增多、皮疹、恶心(口服时)等。对甲吡唑过敏者禁用。

6　注意事项
据研究表明，甲吡唑可以抑制乙醇脱氢酶，而反过来乙醇有可抑制甲吡唑代谢，因而甲吡唑和乙醇可以相互抑制对方的消除，从而加强各自的作用。故临床上应注意乙醇和甲吡唑之间的这种相互作用。

【原产地英文商品名】ANTIZOL 1GM/ML 1.5ML/VIAL
【原产地英文药品名】FOMEPIZOLE
【中文参考商品译名】ANTIZOL 1克/毫升 1.5毫升/瓶
【中文参考药品译名】甲吡唑
【生产厂家中文参考译名】PALADIN LABS
【生产厂家英文名】PALADIN LABS
Antizol
Generic Name: fomepizole (foe MEP i zole)
Brand Names: Antizol

What is Antizol (fomepizole)?
Fomepizole is an antidote to certain types of poison.

Fomepizole is used to treat poisoning with ethylene glycol (antifreeze) or methanol (contained in solvents, fuels, and other household or automotive chemicals). Fomepizole is sometimes used together with hemodialysis to rid the body of a poison.

Fomepizole may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about Antizol (fomepizole)?
In a poisoning situation, it may not be possible to tell your caregivers that you are pregnant or breast-feeding before you are treated with fomepizole. However, make sure any doctor caring for your pregnancy or your baby knows that you have received the medication.

Tell your caregivers at once if you have any burning, swelling, or skin changes where the medicine was injected.

To be sure this medication is helping your condition, your blood and urine will need to be tested often. This will help your doctor determine how long to treat you with fomepizole. You will also be watched for any effects of the poisoning, such as problems with vision, breathing, or urination.

What should I discuss with my health care provider before receiving Antizol (fomepizole)?
You should not receive this medication if you are allergic to fomepizole. FDA pregnancy category C. This medication may be harmful to an unborn baby and is not recommended in pregnant women unless clearly needed. It is not known whether fomepizole passes into breast milk or if it could harm a nursing baby.

In a poisoning situation, it may not be possible to tell your caregivers that you are pregnant or breast-feeding before you are treated with fomepizole. However, make sure any doctor caring for your pregnancy or your baby knows that you have received the medication.

How is fomepizole given?
Fomepizole is given as an injection through a needle placed into a vein. You will receive this injection in a hospital or emergency setting. The medicine must be given slowly through an IV infusion, and each dose can take up to 30 minutes to complete.

To be sure this medication is helping your condition, your blood and urine will need to be tested often. This will help your doctor determine how long to treat you with fomepizole. You will also be watched for any effects of the poisoning, such as problems with vision, breathing, or urination.

What happens if I miss a dose?
Since fomepizole is given as needed by a healthcare professional, it is not likely that you will miss a dose.

What happens if I overdose?
Tell your caregivers right away if you think you have received too much of this medicine.
Overdose symptoms may include nausea, dizziness, or a spinning sensation.

What should I avoid while receiving Antizol (fomepizole)?
Follow your doctor's instructions about any restrictions on food, beverages, or activity after you are treated with fomepizole.

Antizol (fomepizole) side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Tell your caregivers at once if you have any of these serious side effects (some are effects of the poison and not of fomepizole):
burning, swelling, or skin changes where the medicine was injected;
urinating less than usual or not at all;
fast or slow heart rate, feeling like you may pass out; or
skin rash, bruising, severe tingling, numbness, pain, muscle weakness.

Less serious side effects may include:
mild skin rash;
heartburn, nausea, vomiting, diarrhea;
loss of appetite;
dizziness, drowsiness, anxiety, or headache;
metallic taste in your mouth;
hangover feeling;
back pain;
sore throat;
ringing in your ears; or
changes in vision, changes in smell or taste senses.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Antizol (fomepizole)?
Tell your doctor if you have recently used any of the following drugs:
phenytoin (Dilantin);
carbamazepine (Carbatrol, Tegretol);
cimetidine (Tagamet); or
ketoconazole (Nizoral).

There may be other drugs that can affect fomepizole. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors.

Where can I get more information?
Your doctor or pharmacist can provide more information about fomepizole.

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

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. 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. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.