乙胺丁醇
乙胺丁醇是一種合成的抑菌性抗分枝桿菌藥物，主要作為多重藥物療法（「雞尾酒療法」）的一部分，用於治療頑固的分枝桿菌感染（如結核分枝桿菌、牛分枝桿菌、禽分枝桿菌複合群等）。 **臨床重點：** 由於會快速產生抗藥性，嚴禁單獨使用此藥。通常與利福平 (rifampin)、異煙肼 (isoniazid) 等藥物合併使用。 > **重要公共衛生注意事項：** 由於具有顯著的人畜共通傳染潛在風險，特別是對家中免疫力低下的人群構成威脅，在獸醫學中治療這些感染存在高度爭議。
作用機制: Ethambutol is active only against actively dividing mycobacteria. Mechanistically, it inhibits the enzyme **arabinosyl transferase** → disrupts the synthesis of arabinogalactan → prevents the incorporation of **mycolic acid** into the mycobacterial cell wall. This disruption increases cell wall permeability, which allows other antimycobacterial drugs (like rifampin or isoniazid) to penetrate the cell more effectively. It also interferes with RNA synthesis. It has no appreciable activity against other non-mycobacterial bacteria or fungi.
各物種劑量
- Treatment of feline tuberculosis (resistant cases) · 15 mg/kg PO once daily · PO · once daily · Not specified · Considered if resistance develops to initial therapy. Used in combination with rifampin and isoniazid.
- Treatment of M. avium infections in caged birds (Protocol 1) · 20 mg/kg PO q12h · PO · q12h · 6-12 months · Used with Ciprofloxacin/Enrofloxacin, Clofazimine, and Cycloserine.
- Treatment of M. avium infections in caged birds (Protocol 2) · 30 mg/kg PO once daily · PO · once daily · 6-12 months · Used with Clofazimine and Rifampin.
- Treatment of M. avium infections in caged birds (Protocol 3) · 30 mg/kg PO once daily · PO · once daily · 6-12 months · Used with Ciprofloxacin/Enrofloxacin and Rifampin/Rifabutin.
- Avian mycobacteriosis · 30-85 mg/kg PO once daily · PO · once daily · 9-12 months · Used with Rifabutin, Clarithromycin, and Enrofloxacin.
- Treatment of disseminated M. tuberculosis · 10-25 mg/kg PO once daily · PO · once daily · More than 9 months · Used in combination with rifampin (5-10 mg/kg PO q12-24h) and isoniazid (10-20 mg/kg PO once daily). May also add pyrazinamide (ineffective for M. bovis).
劑量為合格獸醫專業人員的臨床參考。請務必對照最新藥品仿單及個別病患確認。
給藥途徑
禁忌症
- Patients with a history of prior hypersensitivity reactions to ethambutol
不良反應
- Optic neuritis (decreased visual acuity, usually reversible)
- CNS degenerative changes (with prolonged use)
- Myocardial toxicity (at high doses)
- Depigmentation of the tapetum lucidum
- Bacterial or fungal overgrowth (due to prolonged multi-drug antimicrobial therapy)
藥物相互作用
- Aluminum-containing antacids · Can reduce oral absorption of ethambutol; separate dosing by at least 4 hours if both are necessary
監測
- Clinical efficacy
- Visual function (periodic monitoring with long-term therapy)
- Liver function
- Renal function
- CBC
- Monitor for fungal or bacterial overgrowth infections
過量
Very limited veterinary information exists. In humans, acute overdoses of >10 grams have caused **optic neuritis**. Other adverse effects noted with human overdoses include CNS effects (confusion, visual hallucinations), abdominal pain, nausea, fever, and headache. Treatment is supportive.
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用,不能取代專業判斷或廠方最新藥品說明書。