性状：本品具有广谱抗菌作用，对多数革兰阳性及阴性菌均有抑制作用，但抑菌作用较弱，而对结核分枝杆菌具有较好的抑制作用，但仍较异烟肼、链霉素弱，优点是不易产生耐药性，对耐药结核菌也有效，最低抑菌浓度为25mg/L，其作用机制为抑制细菌细胞壁的合成。

作用与作用机制：本品口服吸收迅速，服药4-8h达血药浓度峰值，口服2次/d，250mg/次，血药浓度可维持20-30mg/L。本品吸收后，广泛分布于全身体液和组织，易透过血脑屏障，脑脊液、胸水、胎盘血及母乳中药物浓度与血药浓度相近。服药72h后，65%以原形经肾排泄，其余在体内分解代谢。

药动学：可见神经-精神系统反应如头痛、眩晕、定向或记忆障碍、震颤、抽搐、嗜睡、昏迷等，并出现精神障碍和自杀倾向。也可出现过敏反应。患有癫痫、严重忧郁、烦躁或精神病，严重肝、肾功能障碍者不宜使用。不良反应的发生与血药浓度及给药剂量相关，治疗时最好能控制血药浓度在30mg/L之内，若每日剂量＞1g时可引起急性中毒，每日剂量≥1.5g时可突发心力衰竭。

功能主治：抗结核杆菌作用远比异烟肼、链霉素弱，但细菌对之不易产生耐药性，主要用于耐药结核杆菌的感染

用法计量：成人口服，0.5-1g/d，分2次,最初2周，2次/d，250mg/次为宜。最大剂量每日不超过1.0g 。儿童口服每日10mg/kg，分2-4次服，首剂用半量。

剂型：片剂：25mg；胶囊剂：250mg。

【原产地英文商品名】MYSER(SEROMYCIN EQUIVALENT) 250mg/tab 10tabs/box
【原产地英文药品名】CYCLOSERINE
【中文参考商品译名】MYSER(等效于SEROMYCIN) 250毫克/片 10片/盒
【中文参考药品译名】环丝氨酸
该药品相关信息网址1:http://www.drugs.com/cons/seromycin.html

该药品相关信息网址2:http://www.medicinenet.com/cycloserine_capsule_oral/article.htm

GENERIC NAME: CYCLOSERINE - ORAL (sye-klo-SER-een)

USES: This medication is used with other medications to treat tuberculosis (TB). In some cases, it may also be used to treat urinary tract infections (UTIs). It works by stopping the growth of  bacteria.This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Unnecessary use or misuse of any antibiotic can lead to its decreased effectiveness.

HOW TO USE: Take this medication by mouth with or without food, usually twice daily (every 12 hours) or as directed by your doctor.The dosage is based on your weight, medical condition, cycloserine blood levels, and response to treatment. Do not take more than 1000 mg per day.Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, take it at the same times each day.Continue to take this medication (and other TB medications) until the full prescribed amount is finished, even if symptoms disappear. Stopping the medication too early or skipping doses may allow the bacteria to continue to grow, which may result in a return of the infection and cause the infection to be more difficult to treat (resistant).Your doctor may also direct you to take vitamin B6 (pyridoxine) to help prevent certain side effects from cycloserine. Follow your doctor's instructions carefully.Tell your doctor if your condition persists or worsens.

SIDE EFFECTS: Headache, drowsiness, dizziness, or shaking (tremor) may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor immediately if any of these unlikely but serious side effects occur: weakness, mental/mood changes (such as confusion, agitation, hallucination, depression, thoughts of suicide), numb/tingling skin, seizures.Tell your doctor immediately if any of these rare but serious side effects occur: swelling ankles/feet, irregular heartbeat, unusual tiredness, pale skin.A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking cycloserine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: seizures, mental/mood disorders (such as depression, anxiety, psychosis), kidney disease, liver disease, alcohol use.This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Avoid alcoholic beverages.Cycloserine may cause live bacterial vaccines (such as typhoid vaccine) not to work as well.

Therefore, do not have any immunizations/vaccinations while using this medication without the consent of your doctor.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.This medication passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: The effects of some drugs can change if you take other drugs or herbal products at the same time. This can increase your risk for serious side effects or may cause your medications not to work correctly. These drug interactions are possible, but do not always occur. Your doctor or pharmacist can often prevent or manage interactions by changing how you use your medications or by close monitoring.To help your doctor and pharmacist give you the best care, be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before starting treatment with this product. While using this product, do not start, stop, or change the dosage of any other medicines you are using without your doctor's approval.Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and narcotic pain relievers (such as codeine).Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.Also report the use of drugs which might increase seizure risk when combined with cycloserine including phenothiazines (such as thioridazine), theophylline, or tricyclic antidepressants (such as amitriptyline), among others. Consult your doctor or pharmacist for details.This document does not contain all possible drug interactions. Keep a list of all the products you use. Share this list with your doctor and pharmacist to lessen your risk for serious medication problems.

OVERDOSE: If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: numb/tingling skin, confusion, agitation, hallucinations, seizures.

NOTES: Do not share this medication with others.Laboratory and/or medical tests (such as sputum test, cycloserine blood levels, kidney/liver function, complete blood count) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.

MISSED DOSE: For the best possible benefit, it is important to take each scheduled dose of this medication as directed. If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

STORAGE: Store at room temperature between 68-77 degrees F (20-25 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.