去鐵胺甲磺酸鹽
**去鐵胺 (Deferoxamine mesylate)** 是一種高度專一的**鐵螯合劑**，在獸醫學中主要作為急性鐵中毒（例如誤食鐵劑補充品或脫氧劑）的救命解毒劑。它偶爾也被用於評估治療鋁中毒及作為急性心肌缺血的輔助治療，但其在再灌注損傷的療效並不理想。 主要臨床重點： * **高親和力**：能特異性地標靶並結合血液與組織中的游離鐵，防止鐵引發的氧化損傷。 * **尿液變色**：成功螯合的標誌是產生鮭魚粉色或「玫瑰紅 (vin rosé)」色的尿液，這表示鐵-螯合物複合物正在被排出。 * **給藥方式**：必須以腸胃外途徑給藥（通常為肌肉注射或緩慢靜脈連續輸注）。一般禁忌口服給藥，因為這可能會反常地增加胃腸道對鐵的吸收。
作用機制: Deferoxamine acts by directly binding to free iron to neutralize its toxicity: * The drug possesses three hydroxamic groups that have a high affinity for **ferric (Fe³⁺) ions**. * Deferoxamine + Fe³⁺ → **Ferrioxamine** (a stable, water-soluble chelate complex). * By sequestering the iron, it prevents the metal from participating in the **Fenton reaction**, thereby halting the production of damaging reactive oxygen species (hydroxyl radicals). * The ferrioxamine complex is then readily excreted by the kidneys into the urine. It does not significantly chelate other essential trace metals or electrolytes (except aluminum).
各物種劑量
- Severe iron toxicosis · 40 mg/kg IM q4-8 hours · IM · q4-8h · Until urine clears or serum iron levels return to normal · Cat dosages are not well established; extrapolated from general animal doses.
- Severe iron toxicosis · 15 mg/kg/hour · IV · CRI · 2-3 days · Cat dosages are not well established; extrapolated from general animal doses.
- Severe iron toxicosis · 10 mg/kg IM or IV q8h for 24 hours · IM/IV · q8h · 24 hours · Cat dosages are not well established.
- Severe iron toxicosis · 40 mg/kg IM q4-8 hours · IM · q4-8h · Until urine clears or serum iron levels return to normal · Most effective within the first 24 hours. IM route is preferred as too rapid IV administration can cause hypotension and pulmonary edema.
- Severe iron toxicosis · 15 mg/kg/hour · IV · CRI · 2-3 days (until serum iron < 300 microliters/dL or below TIBC) · Initiate ASAP or at least within 12 hours of ingestion. Give as a constant rate infusion. If CRI not possible, give 40 mg/kg IM q4-8h.
- Severe iron toxicosis · 10 mg/kg IM or IV q8h for 24 hours · IM/IV · q8h · 24 hours
- Ferric ion chelator during treatment of cardiac arrest (experimental) · 5-15 mg/kg IV , IM or SC · IV/IM/SC · Single dose or as directed
- Ferric ion chelator during treatment of cardiac arrest (experimental) · 10 mg/kg IV , IM q2h twice, then three times daily for 24 hours · IV/IM · q2h twice, then TID · 24 hours
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
- Severe renal failure (unless dialysis is used to remove the ferrioxamine complex)
不良反應
- Allergic reactions (hives, wheezing)
- Auditory neurotoxicity (with chronic, high-dose therapy)
- Pain or swelling at injection sites
- Gastrointestinal distress
- Hypotension, tachycardia, and convulsions (if given IV too rapidly)
- Pulmonary edema (associated with rapid IV administration)
藥物相互作用
- Prochlorperazine · Concurrent use may cause temporary impairment of consciousness.
- Vitamin C (Ascorbic Acid) · May be synergistic in removing iron, but could lead to increased tissue iron toxicity, especially in cardiac muscle. Use with extreme caution in patients with preexisting cardiac disease.
監測
- Serum iron levels
- Total iron-binding capacity (TIBC)
- Serum ferritin
- Urine color (monitor for clearing of the 'vin rosé' color)
- Blood pressure and heart rate (especially during IV infusion)
- Ophthalmic examinations (if used chronically)
過量
Acute overdosage or excessively rapid IV administration can lead to severe hypotension, tachycardia, convulsions, hives, wheezing, and pulmonary edema. Chronic high-dose use may lead to hypocalcemia, thrombocytopenia, and auditory/visual neurotoxicity. Treatment is supportive and symptomatic.
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。