泰拉黴素
**泰拉黴素 (Tulathromycin)** 是一種半合成、長效型的三胺基巨環類抗生素。主要應用於大型動物（牛和豬）的醫學中，用於治療呼吸道疾病、牛腐蹄病及傳染性牛角結膜炎（粉紅眼）。 * **獨特結構**：含有三個胺基（三元鹼），使其比傳統巨環類藥物更能有效穿透革蘭氏陰性病原體。 * **標靶遞送**：大量積聚於宿主的吞噬細胞（巨噬細胞和嗜中性球）中，將高濃度的藥物直接遞送至受感染的肺部組織。 * **便利性**：由於其在組織中的半衰期極長（在牛肺中可達 8.75 天），因此設計為單劑量給藥。 > **臨床要點**：雖然主要核准用於經濟動物，但偶爾也會標示外使用於治療馬駒的馬紅球菌 (*Rhodococcus equi*) 感染，以及小型反芻動物的易感呼吸道病原體感染。
作用機制: Tulathromycin binds to the **50S ribosomal subunit** of susceptible bacteria → blocks transpeptidation and translocation processes → inhibits RNA-dependent protein synthesis. * Generally considered **bacteriostatic**, but exhibits **bactericidal** activity against key respiratory pathogens like *Mannheimia haemolytica* and *Pasteurella multocida*. * Its low affinity for bacterial efflux pumps allows it to remain and accumulate within the bacteria. * Concentrates in host phagocytic cells (macrophages) → migrates to sites of inflammation → releases active drug directly at the infection site, providing targeted therapy.
各物種劑量
- Bovine respiratory disease (BRD), bovine foot rot, infectious bovine keratoconjunctivitis (IBK) · 2.5 mg/kg (1.1 mL/100 lb) BW · SC · single dose · Inject subcutaneously in the neck. Do not inject more than 10 mL per injection site.
- Rhodococcus equi infections in foals · 2.5 mg/kg · IM · every 5-7 days · Anecdotally used successfully in milder clinical cases.
- Swine respiratory disease (SRD) · 2.5 mg/kg (0.25 mL/22 lb) BW · IM · single dose · Inject intramuscularly in the neck. Do not inject more than 2.5 mL per injection site.
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。
給藥途徑
禁忌症
- Prior hypersensitivity to tulathromycin or other macrolides
- Female dairy cattle 20 months of age or older
- Calves to be processed for veal
- Pre-ruminating calves (withdrawal period not established)
不良反應
- Transient hypersalivation
- Transient dyspnea (rare)
- Injection site reactions (swelling, pain, discoloration, trim loss at slaughter)
- Anorexia
- Restlessness and excessive vocalization (swine)
監測
- Clinical efficacy (resolution of respiratory signs, lameness, or ocular lesions)
- Injection site for severe reactions
過量
### Cattle Single subcutaneous doses of up to 25 mg/kg caused transient indications of pain at the injection site, including head shaking and pawing at the ground. Injection site swelling, discoloration of subcutaneous tissues, and corresponding histopathologic changes were observed. ### Swine Single IM doses of up to 25 mg/kg caused transient indications of pain at the injection site, restlessness, and excessive vocalization. Brief tremors occurred in one animal receiving 7.5 mg/kg. ### Treatment No systemic treatment for single overdoses should be necessary. Localized treatment at the injection site (e.g., ice pack) to reduce swelling and pain, as well as FDA-approved analgesic medications, can be considered.
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。