Viramune(Nevirapine)
药品英文名
Nevirapine
药品别名
奈维平、维乐命、尼维拉平、奈维雷平、Viramune、NVP
药物剂型
片剂：200mg。
药理作用
奈韦拉平是一种非核苷类反转录酶抑制剂，可抑制HIV反转录酶。其结合部位为反转录酶的P66亚基中的亲脂性袋状结构，与反转录酶结合后可削弱反转录酶的聚合作用，从而抑制HIV-1的复制。其对核苷敏感的或耐核苷类药物的HIV病毒株均有抗毒活性。
药动学
口服吸收良好，生物利用度为80%～90%，血浆药物浓度达峰时间为1h，血浆峰浓度为1.1～1.5μg/ml。与食物同服可延迟达峰时间0.25～2.5h，峰浓度下降10%～40%，但生物利用度不变。静注给药平均分布容积为1.3L/kg。在体内可通过血-脑脊液屏障，并进入脑脊液中，血浆蛋白结合率为16%～36%。在肝仅5%～10%被代谢为反式硫氧化物的衍生物，血浆半衰期为5～7h。主要以原形药物经肾排泄，由肾清除约占剂量的70%左右。肝肾功能不全者几不影响本品的代谢，对老年肾功能不全者其代谢尚无显著改变。
适应证
用于与其他核苷类反转录酶抑制剂或非核苷类反转录酶抑制剂联用治疗进展性HIV疾病(CD4细胞数计数≤500/mm3)，乙型病毒复制的慢性乙型肝炎。
禁忌证
1.妊娠及哺乳妇女禁用。
2.对本品过敏者禁用。
注意事项
1.肾功能严重不全、乙型肝炎引起的晚期肝病、糖尿病、胰腺炎患者慎用。
2.本品与地拉韦定有交叉耐药性。
3.为减少发生皮疹的危险，初始剂量以每次200mg，每天1次，如确认未发现皮疹，可使用维持剂量每次200mg，每天2次。
不良反应
1.常见发生的不良反应有皮疹、多形糜烂性红斑、发热、恶心、头痛、贫血、血小板减少、肝酶(AST或ALT)和血清淀粉酶增高。
2.偶见疲劳、腹泻、呕吐、腹痛、失眠、咳嗽、鼻部症状。
3.皮疹常出现于治疗早期，严重者可危及生命。
用法用量
口服：每次200mg，每天2次；或首服每天200mg，连续14天，后以每次200mg，每天2次。
药物相应作用
本品可诱导肝药物代谢酶P450中CYP3A同工酶，可降低口服避孕药、其他蛋白酶抑制剂的血浆浓度，不宜与上述药物联合应用。与其他核苷类似物HIV药物联合应用，可降低皮疹的发生率。
专家点评
本品适用于与核苷类逆转酶抑制剂合用治疗临床或免疫学恶化的HIV感染者。单用本品或与一种核苷类药物联合应用易使HIV产生耐药性，对未经治疗的早期或晚期HIV患者，在增加CD4细胞计数的同时可使血浆治疗者血浆HIV-RNA显著较低至定量检测水平以下。本品加齐多夫定、去羟肌苷联合治疗连续1年比齐多夫定单加去羟肌苷更为有效。对曾进行过广泛治疗的HIV患者，本品加齐多夫定、去羟肌苷联合治疗在增加CD4细胞计数和降低血浆HIV-RNA水平上，比齐多夫定单加去羟肌苷更为有效，但疾病的进展速率和病死率仍类似。国外报道，一项临床研究证实，本品与拉米夫定、茚地那韦联合应用，在连续24周内产生良好的病毒学效果。
Viramune (nevirapine)
Pronunciation(s): VIH-rah-mune; nah-VAIR-ah-peen
Viramune
Generic name: Nevirapine
Why is Viramune prescribed?
Viramune is prescribed for advanced cases of HIV. HIV—the human immunodeficiency virus that causes AIDS—undermines the immune system over a period of years, eventually leaving the body defenseless against infection. Viramune is generally prescribed only after the immune system has declined and infections have begun to appear. It is always taken with at least one other HIV medication such as Retrovir or Videx. If taken alone, it can cause the virus to become resistant. Even if used properly, it may be effective for only a limited time.
Like other drugs for HIV, Viramune works by impairing the virus's ability to multiply.
Most important fact about Viramune
The most important side effect of Viramune is a rash which occasionally becomes so serious as to be life-threatening. The rash strikes approximately one in four patients, and becomes severe in about 2 percent. It usually appears during the first 6 weeks of therapy and strikes women more often than men. If you notice any signs of a rash, inform your doctor immediately. If it becomes severe or is accompanied by fever, blisters, mouth sores, red eyes, swelling, muscle or joint aches, or general fatigue, stop taking the drug and call your doctor.
How should you take Viramune?
Be sure to take this medication every day, exactly as prescribed. Increase the dosage only when directed. To avoid development of resistance, be careful to take your other HIV drugs as well.
If you are using the oral suspension, shake it gently before each dose. Give it to the child with an oral dosing syringe or dosing cup. After each dose, rinse the cup with water and give the rinse to the child as well.
If you miss a dose.
Take it as soon as you remember. If it is almost time for the next dose, skip the one you missed and go back to your regular schedule. Do not double the dose.
Storage instructions...
Store tablets and oral suspension at room temperature in a tightly closed bottle.
What side effects may occur?
Side effects cannot be anticipated. If any develop or change in intensity, inform your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue using Viramune.
Side effects may include:
Abdominal pain, allergic reactions (including hives, blisters, mouth sores, or swollen mouth and throat), anemia, diarrhea, drowsiness, drug withdrawal, fat redistribution, fatigue, fever, headache, joint pain, liver damage, muscle aches, nausea, rash, tingling, vomiting
Why should Viramune not be prescribed?
If Viramune gives you an allergic reaction, you cannot use this drug.
You should also avoid Viramune if you have severe liver impairment.
Special warnings about Viramune
Viramune has been known to cause serious—even fatal—liver damage, especially during the first 18 weeks of therapy. People with hepatitis B or C and women with a CD4+ cell count above 250 are more likely to develop this problem. Overall, women are at greater risk than men. If you already have moderate liver impairment, use Viramune with caution, if at all. Warning signs of liver damage include fatigue, a vaguely ill feeling, poor appetite, nausea, yellowish skin or eyes, pale stools, dark urine, and tenderness in the midriff. Check with your doctor immediately if you develop these symptoms. If liver damage has occurred, you'll have to permanently discontinue Viramune therapy.
You should know that HIV medications also cause a redistribution of fat in some people, increasing the amount of fat found around the middle and on the upper back, and reducing the amount of fat in the arms, legs, and face.
Remember that Viramune does not completely eliminate HIV from the body. The virus can still be passed to others during sex or through blood contamination.
Though Viramune can slow the progress of HIV, it is not a cure. HIV-related infections remain a danger, so frequent check-ups and tests are still advisable.
Possible food and drug interactions when taking Viramune
If Viramune is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Viramune with the following:
Clarithromycin (Biaxin)
Efavirenz (Sustiva)
Fluconazole (Diflucan)
Indinavir (Crixivan)
Ketoconazole (Nizoral)
Lopinavir/Ritonavir (Kaletra)
Methadone (Dolophine)
Nelfinavir (Viracept)
Rifabutin (Mycobutin)
Rifampin (Rifadin, Rimactane)
St. John's wort
Saquinavir (Fortovase)
Zidovudine (Retrovir)
Viramune may interfere with birth control pills and other hormonal contraceptives. Do not use this form of contraception during Viramune therapy.
Also, it's important to talk to your doctor before combining Viramune with any of the following:
Antiarrhythmic heart medications such as disopyramide (Norpace)
Anticonvulsant (seizure) medications such as carbamazepine (Tegretol), clonazepam (Klonopin)
Antifungal medications such as itraconazole (Sporanox)
Blood-thinning medications such as warfarin (Coumadin)
Calcium channel blocker (angina) medications such as diltiazem (Cardizem), nifedipine (Procardia), verapamil (Calan)
Cancer chemotherapy medications such as cyclophosphamide (Cytoxan)
Immunosuppressant medications such as cyclosporine (Sandimmune, Neoral)
Migraine medications such as ergotamine (Cafergot)
Opiate agonists (narcotic) pain medications such as fentanyl (Duragesic)
Special information if you are pregnant or breastfeeding
If you are pregnant you may be at a higher risk of developing serious—even fatal—liver damage while taking Viramune. If you are pregnant or plan to become pregnant, notify your doctor immediately.
Avoid breastfeeding. HIV can be passed to a nursing infant through breast milk.
Recommended dosage for Viramune
ADULTS
For the first 14 days, the dose is 1 tablet a day. If no serious rash appears, the dose is then increased to 1 tablet twice a day. If you miss your doses for more than 7 days, the doctor will have to restart you at the lower initial dose.
CHILDREN
2 months to 8 years of age
For the first 14 days, the dose of oral suspension is 4 milligrams per 2.2 pounds of body weight once a day. If no serious rash appears, the dose is then increased to 7 milligrams per 2.2 pounds twice a day.
8 years and older
For the first 14 days, the dose of oral suspension is 4 milligrams per 2.2 pounds of body weight once a day. If no serious rash appears, the dose is then increased to 4 milligrams per 2.2 pounds twice a day.
For both adults and children, total daily dosage should never exceed 400 milligrams (2 tablets).
In certain cases your Viramune dosage may need to be adjusted. Be sure to tell the doctor if you develop a rash within the first 14 days of using Viramune or if you stop taking the drug for more than 7 days. Also tell the doctor if you're undergoing kidney dialysis.
If you develop hepatitis during Viramune treatment, you will have to stop taking the drug.
Overdosage
Any medication taken in excess can have serious consequences. If you suspect an overdose, seek medical attention immediately.
Symptoms of Viramune overdose may include:
Dizziness, fatigue, fever, headache, insomnia, nausea, rash, reddened bumps on the skin, respiratory problems, swelling, vomiting, weight los.
