孟魯司特鈉
**孟魯司特鈉 (Montelukast sodium)** 是一種白三烯受體拮抗劑。在獸醫學中，主要用於**貓**的標示外治療，包括： * **貓氣喘** * **炎症性腸病 (IBD)** * 慢性上呼吸道感染 * **心絲蟲相關呼吸道疾病 (HARD)** > **臨床提示：** 雖然理論上可透過阻斷發炎介質來治療貓氣喘，但臨床療效通常不如預期。一般作為二線或三線輔助療法，而非首選藥物。一項針對患有反覆性呼吸道阻塞 (RAO) 馬匹的小型試驗也未能顯示其療效。在人類醫學中，獲 FDA 核准用於過敏性鼻炎和氣喘。
作用機制: Montelukast acts as a highly selective and competitive **cysteinyl leukotriene receptor (CysLT1) antagonist**. * Arachidonic acid → 5-lipoxygenase pathway → **Cysteinyl leukotrienes (LTC4, LTD4, LTE4)**. * These leukotrienes are potent inflammatory mediators released by **mast cells** and **eosinophils**. * By blocking the **CysLT1 receptor** in the airways and gastrointestinal tract, montelukast prevents leukotriene-mediated bronchoconstriction, mucosal edema, vascular permeability, and eosinophil recruitment.
各物種劑量
- Feline asthma · 0.5-1 mg/kg PO once daily (q24h) · PO · q24h · Anecdotal reports of efficacy; more conclusive evidence is needed before regular use.
- Adjunctive treatment of the chronic 'snuffler' · 0.25-0.5 mg/kg PO q24h · PO · q24h · i.e., 1/8th of a 10 mg Singulair tablet.
- Inflammatory Bowel Disease (IBD) · 0.5-1 mg/kg PO once daily · PO · q24h · For mild cases involving eosinophils and lymphocytes. May be used in combination with other drugs.
- Adjunctive treatment of feline heartworm · 2 mg total dose (PO) once daily · PO · q24h · Anecdotal evidence suggests it may help thwart acute, fatal lung injury when an adult worm dies.
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
- Hypersensitivity to montelukast or any component of the product
- Not for use in reversing acute bronchospasm (asthma attacks)
不良反應
- No significant adverse effects reported in cats to date
- Humans (rare): behavioral effects (aggression, suicidal thoughts), palpitations, cholestatic hepatitis, allergic granulomatous angiitis
藥物相互作用
- Phenobarbital · CYP-450 enzyme inducer; may reduce montelukast plasma concentrations and efficacy.
- Rifampin · CYP-450 enzyme inducer; may reduce montelukast plasma concentrations and efficacy.
- Prednisone / Prednisolone · Severe peripheral edema has been reported in a human receiving both drugs, presumably due to increased renal tubular sodium and fluid retention. Clinical significance in veterinary patients is unclear.
監測
- Clinical efficacy (improvement in respiratory or GI signs)
過量
**Overdose Toxicity:** Montelukast is relatively safe in overdose situations. * **Animal Data:** Rats and mice survived oral doses of approximately 230X to 335X the usual human adult dose. * **Human Data:** Doses as high as 1,000 mg have been reported with the majority having no adverse effects. * **Clinical Signs (if present):** Headache, vomiting, psychomotor hyperactivity, thirst, somnolence, mydriasis, hyperkinesia, and abdominal pain. * **Treatment:** Basically supportive. No specific antidote is known.
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。