鉄デキストラン
鉄デキストランは、主に新生の食肉用動物（子豚など）における**鉄欠乏性貧血**の治療および予防に使用される注射用造血剤です。子豚は出生時の鉄貯蔵量が少なく、屋内飼育では土壌からの鉄分摂取ができないため、貧血予防のための早期補給が不可欠です。 小動物医療においては、特に経口鉄剤の忍容性が低い、または吸収が不十分な慢性腎臓病の患者に対する**エリスロポエチン（EPO）**やダルベポエチン治療の補助療法として頻繁に使用されます。 > **臨床上のポイント：** 鉄の投与は鉄欠乏に起因する身体症状やヘモグロビン低下を改善しますが、それ自体が赤血球生成を刺激するわけではなく、他の原因による貧血を改善するものではありません。
作用機序: Iron is an essential structural component of **hemoglobin** and **myoglobin**, facilitating oxygen transport and utilization throughout the body. It also acts as a critical cofactor for multiple metabolic enzymes. * **Pathway:** IM Injection → Slow absorption via lymphatic system → Phagocytosis by reticuloendothelial system (RES) in liver, spleen, and bone marrow → Cleavage of iron from dextran → Iron binds to **transferrin** for transport → Incorporation into **hemoglobin** in bone marrow or stored as **ferritin** and **hemosiderin**. * **Key Enzymes:** Ionized iron is a vital component of **cytochrome oxidase**, **succinic dehydrogenase**, and **xanthine oxidase**.
動物種別の用量
- Prevention of transient neonatal iron deficiency anemia · 50 mg iron dextran injection at 18 days of age · IM · once
- Adjunctive therapy with erythropoietin treatment · 10 mg/kg IM every 3-4 weeks · IM · q3-4 weeks
- Adjunctive therapy with erythropoietin treatment in cats who cannot tolerate oral iron therapy · 50 mg IM q3-4 weeks · IM · q3-4 weeks
- General · 10 mg/kg IM once weekly · IM · weekly
- Iron deficiency anemia or following hemorrhage · 10 mg/kg IM; repeat in 7-10 days if PCV fails to return to normal · IM · once, repeat in 7-10 days if needed
- Iron deficiency anemia or following hemorrhage · 10 mg/kg IM; repeat weekly · IM · weekly
- Prevention of iron deficiency anemia in baby pigs (2-4 days of age) · Administer an initial intramuscular injection of 100 mg of elemental iron to each animal at 2 to 4 days of age. Dosage may be repeated in 14 to 21 days. · IM · once, repeat in 14-21 days
- Iron deficiency anemia · 10-20 mg/kg once, followed by oral therapy with ferrous sulfate · IM · once · Followed by oral therapy with ferrous sulfate
投与経路
禁忌
- Known hypersensitivity to iron dextran
- Any anemia other than iron deficiency anemia
- Acute renal infections
- Concurrent use with oral iron supplements
有害事象
- Prostration and muscular weakness (pigs)
- Anaphylactoid reactions (rarely fatal)
- Nausea, vomiting, and sudden death within 1 hour (in pigs born to Vitamin E/Selenium deficient sows)
- Muscle tissue staining at injection site (in pigs >4 weeks old)
- Injection site sarcomas (associated with large SC doses in laboratory animals)
薬物相互作用
- Chloramphenicol · May delay the response to iron administration; avoid using chloramphenicol in patients with iron deficiency anemia
モニタリング
- CBC (Complete Blood Count)
- RBC indices (MCV, MCHC)
- Adverse reactions (especially post-injection anaphylaxis)
- Serum iron (Note: values may not be meaningful for up to 3 weeks post-injection)
過量投与
Inadvertent overdose injections may lead to iron toxicity, which can cause severe gastrointestinal mucosal damage, cardiovascular collapse, and liver failure. Depending on the size of the dose, chelation therapy may be required. **Deferoxamine** is the specific chelating agent used for severe iron toxicity.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。