米托坦
Mitotane
o,p'-DDD (1-chloro-2-[2,2-dichloro-1-(4-chlorophenyl)ethyl]benzene)
別名: Lysodren · o,p'-DDD · CB-313 · NSC-38721 · WR13045 · Lisodren
由 VetSheet 獸醫團隊審訂更新於 2026年4月5日本內容以實證獸醫文獻為本
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各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Pituitary-dependent hyperadrenocorticism (Induction - Protocol A) | 25 mg/kg twice a day, PO with food | PO | q12h | Until clinical endpoints occur (usually 4-9 days) | 🌎 NA |
| Pituitary-dependent hyperadrenocorticism (Maintenance - Protocol A) | 25-50 mg/kg per week | PO | Divided in as many doses as possible weekly | Long-term | 🌎 NA |
| Pituitary-dependent hyperadrenocorticism (Induction - Protocol B) | 30-50 mg/kg/day PO with a meal once daily or divided q12h | PO | q24h or q12h | 7-10 days | 🌎 NA |
| Pituitary-dependent hyperadrenocorticism (Maintenance - Protocol B) | 35-50 mg/kg per week in 2-3 divided doses | PO | Divided weekly | Long-term | 🌎 NA |
| Pituitary-dependent hyperadrenocorticism (Induction - Protocol C) | 50 mg/kg divided q12h | PO | q12h | Until water consumption decreases to <100 mL/kg/day or adverse signs observed (usually 3-7 days) | 🌎 NA |
| Pituitary-dependent hyperadrenocorticism (Maintenance - Protocol C) | 50 mg/kg every 7-10 days | PO | Every 7-10 days | Long-term | 🌎 NA |
| Total adrenal ablation (Alternative Protocol D) | 75-100 mg/kg per day for 25 consecutive days, given in 3-4 doses per day with food | PO | Divided q6-8h | 25 days | 🌎 NA |
| Total adrenal ablation (Alternative Protocol E) | 100 mg/kg/day divided twice daily for 30 days | PO | q12h | 30 days | 🌎 NA |
| Palliative medical treatment of adrenal carcinomas or adenomas | 50-75 mg/kg PO in daily divided doses | PO | Divided daily | 10-14 days initially | 🌎 NA |
| Pituitary-dependent hyperadrenocorticism (Induction) | 30-50 mg/kg | PO | q24h | to effect (generally 3-10 days) | 🌍 EU |
| Pituitary-dependent hyperadrenocorticism (Maintenance) | 50 mg/kg | PO | q7-14 days | Ongoing | 🌍 EU |
| Adrenal carcinomas | 50-150 mg/kg | PO | q24h | Ongoing | 🌍 EU |
- Pituitary-dependent hyperadrenocorticism (Induction - Protocol A): Reduce food by 1/3 the day before. Stop therapy if water consumption approaches 60 mL/kg/day, appetite reduces, vomiting, listlessness, or diarrhea occurs.
- Pituitary-dependent hyperadrenocorticism (Maintenance - Protocol A): Adjust based on ACTH stimulation test results.
- Pituitary-dependent hyperadrenocorticism (Induction - Protocol B): Goal is basal and post-ACTH cortisol between 1-5 micrograms/dL.
- Pituitary-dependent hyperadrenocorticism (Induction - Protocol C): Max 5-7 days prior to ACTH stim test if water consumption cannot be monitored.
- Pituitary-dependent hyperadrenocorticism (Maintenance - Protocol C): Dose is highly variable (26-330 mg/kg/week).
- Total adrenal ablation (Alternative Protocol D): Requires lifelong prednisone and mineralocorticoid therapy.
- Total adrenal ablation (Alternative Protocol E): Requires cortisone acetate and fludrocortisone acetate supplementation.
- Palliative medical treatment of adrenal carcinomas or adenomas: May increase to 100 mg/kg/day based on ACTH response. Maintenance is 100-200 mg/kg/week.
- Pituitary-dependent hyperadrenocorticism (Induction): Give with/after food high in fat/oil to improve absorption.
- Pituitary-dependent hyperadrenocorticism (Maintenance): Given in 2-3 divided doses as required. Give with/after food high in fat/oil.
- Adrenal carcinomas: Higher doses may become necessary. Give with/after food high in fat/oil.
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Hyperadrenocorticism | 30-50 mg/kg | PO | q24h | to effect | 🌍 EU |
- Hyperadrenocorticism: Efficacy in cats is very variable, with many showing no response at non-toxic levels. Not recommended.
雪貂
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Medical treatment of hyperadrenocorticism | 50 mg per ferret PO once daily for one week, then 50 mg PO 2-3 times per week | PO | q24h then 2-3 times/week | Long-term | 🌎 NA |
- Medical treatment of hyperadrenocorticism: Have a compounding pharmacy make 50 mg capsules. Can be coated with Nutrical.
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
概覽
米托坦 (Mitotane,又稱 o,p'-DDD) 是一種腎上腺細胞毒性劑,在獸醫學中主要用於內科治療犬隻的腦下垂體依賴型腎上腺皮質機能亢進 (PDH) (庫興氏症候群)。其化學結構與殺蟲劑 DDT 相似。
由於它能引發腎上腺皮質的靶向性壞死,因此能有效減少過量皮質醇的產生。它也可用於人類和犬隻腎上腺癌的姑息性治療。
臨床要點: 治療通常分為兩個不同階段:誘導期 (每日給藥以快速破壞增生的腎上腺組織,直到達到臨床終點) 和 維持期 (每週或每兩週給藥以防止腎上腺皮質重新生長)。由於過度治療可能導致醫源性腎上腺皮質機能低下 (艾迪生氏症),因此必須進行嚴密的監測。
作用機制
Mitotane acts as a targeted adrenocortical cytotoxic agent.
- It causes severe, progressive necrosis and atrophy of the zona fasciculata and zona reticularis of the adrenal gland → drastically reducing the synthesis of glucocorticoids (cortisol).
- It relatively spares the zona glomerulosa, meaning mineralocorticoid (aldosterone) synthesis is usually unaffected, though clinically significant effects on aldosterone production can occasionally occur.
- The exact intracellular mechanism of cytotoxicity is not fully understood, but it is believed to involve metabolic activation within the adrenal mitochondria, leading to irreversible binding to cellular macromolecules and subsequent cell death.
安全性與警告
禁忌症
- Known hypersensitivity to mitotane
- Pregnancy (FDA Category C in humans; Class D in veterinary medicine - embryotoxic/teratogenic)
- Patients that are not eating well (should never be administered to anorexic animals)
- Not recommended in cats (trilostane is more effective and mitotane efficacy is highly variable)
不良反應
- Lethargy
- Ataxia
- Weakness
- Anorexia (loss of appetite)
- Vomiting
- Diarrhea
- Neurologic signs (uncommon)
- Liver changes (congestion, centrolobular atrophy, fatty degeneration)
- Iatrogenic hypoadrenocorticism (requiring long-term glucocorticoid/mineralocorticoid replacement in ~5% of dogs)
- Diarrhoea
- Acute-onset neurological signs (2-3 weeks post-initiation)
注意事項
Warning: Mitotane should never be administered to animals that are not eating well.
- Diabetes Mellitus: Concurrent diabetes requires close monitoring as insulin requirements may rapidly decrease during initial treatment.
- Organ Dysfunction: Dogs with preexisting renal or hepatic disease should receive the drug with extreme caution and intense monitoring.
- Stress Supplementation: All dogs receiving mitotane therapy must receive additional glucocorticoid supplementation if undergoing physiological stress (e.g., surgery, trauma, acute illness).
- Human Safety: Mitotane is a cytotoxic drug. Caregivers should avoid direct skin contact (wear gloves) and wash hands after administration.
藥物相互作用
Additive depressant effects may be seen if used concomitantly.
Diabetic dogs receiving insulin may have their insulin requirements rapidly decreased when mitotane therapy is instituted.
Can induce enzymes and reduce the efficacy of mitotane; conversely, mitotane can induce hepatic microsomal enzymes and increase the metabolism of phenobarbital.
Has been demonstrated to block the action of mitotane in dogs; an alternate diuretic is recommended.
Increases the hepatic metabolism of mitotane
Increases the hepatic metabolism of mitotane
監測
- Physical exam and history (especially water consumption, food consumption, and weight)
- ACTH response test (crucial for dose adjustment)
- Serum electrolytes (Na+/K+)
- BUN
- CBC
- Liver enzymes
- Appetite (daily during induction)
- ACTH stimulation test (to monitor treatment efficacy)
- Blood glucose (in diabetic patients)
- Clinical signs of weakness, vomiting, or neurological changes
藥物動力學
吸收
Systemic bioavailability in dogs is poor. Oral absorption is significantly enhanced by giving the drug with food (especially food high in oil/fat content). In humans, ~40% is absorbed with peak serum levels at 3-5 hours.
分佈
Distributes to virtually all tissues in the body. It is highly lipophilic, stored in fat, and does not accumulate in the adrenal glands. A small amount may enter the CSF.
代謝
Metabolized in the liver.
排除
Excreted as metabolites in the urine (10%) and bile (15%) within 24 hours of dosing.
過量
Because of the drug's toxicity and very long half-life, acute overdosage should be managed aggressively.
- Decontamination: Emptying the stomach and administering activated charcoal and a cathartic should be considered after a recent ingestion.
- Monitoring & Treatment: The patient must be closely monitored. Administer systemic glucocorticoids (e.g., dexamethasone or prednisone) and IV fluids if signs of acute hypoadrenocorticism (Addisonian crisis) develop.
可用產品
劑型
- Tablets
- 500 mg tablet
- 500 mg capsule
人用標示
- Mitotane Tablets (scored): 500 mg (Lysodren)
- Lysodren 500 mg tablet
各地核准狀態
Available from Europe for animals that have failed trilostane therapy. POM.
POM (Prescription Only Medicine). Used under the cascade.
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Store at room temperature (15-30°C), in tight, light-resistant containers.
飼主須知
- 隨餐服用: 請務必在寵物進食後(最好是含有一些脂肪或油脂的食物)立即給予此藥物,以確保良好的吸收。
- 注意副作用: 此藥物的目的是降低皮質醇濃度,但有時可能會降得太低。請密切觀察您的寵物是否有「艾迪生氏危機」的跡象,包括嗜睡、虛弱、嘔吐、腹瀉或突然食慾不振。
- 生病時停藥: 如果您的寵物停止進食或出現上述任何症狀,請立即停止給藥並聯絡您的獸醫師。獸醫師可能會指示您給予急救劑量的類固醇(如潑尼松)。
- 安全預防措施: 米托坦是一種強效的細胞毒性藥物。處理藥片時請戴上手套,或在給藥後徹底洗手。請將藥物嚴格存放在兒童和其他寵物接觸不到的地方。
- 壓力時期: 在壓力時期(如手術、寄宿或急性疾病),您的寵物可能需要額外的類固醇藥物。請與您的獸醫師討論此情況。
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