ウンデシレン酸ボルデノン
**ウンデシレン酸ボルデノン**は、テストステロンから派生した長時間作用型の注射用**アナボリックステロイド**です。主に獣医学において、衰弱した馬の体重、毛並み、および全身状態の改善を補助するために使用されます。 小動物医療においては、過去に猫の食欲増進剤として適応外使用されていましたが、肝毒性のリスクがあるため、現在ではより安全で効果的な代替薬に取って代わられています。 > **臨床のポイント:** ボルデノンはゴマ油を基剤としたウンデシレン酸エステルとして製剤化されており、筋肉内注射部位からの吸収を遅らせ、数週間にわたる持続的な放出を提供します。筋肉増強作用があるため、米国では**スケジュールIII（C-III）規制薬物**に指定されており、人間による乱用や横流しのリスクが高い薬物です。
作用機序: Boldenone works by binding to intracellular **androgen receptors** in muscle and other tissues → the receptor-steroid complex translocates to the nucleus → alters gene transcription → promotes protein synthesis, nitrogen retention, and tissue building (anabolism) while reversing catabolism. * **Erythropoiesis:** Stimulates red blood cell production, likely by increasing the production of **erythropoietic stimulating factor (erythropoietin)**. * **Endocrine Feedback:** High doses cause negative feedback on the hypothalamus and pituitary gland → inhibits **Luteinizing Hormone (LH)** and **Follicle Stimulating Hormone (FSH)** → suppresses endogenous testosterone release and impedes spermatogenesis. * **Electrolyte Balance:** Causes retention of nitrogen, sodium, potassium, and phosphorus, and decreases urinary excretion of calcium.
動物種別の用量
- As an appetite stimulant · 5 mg (total dose) IM/SC every 7 days · IM/SC · q7d · Anabolic steroids not as effective as many other appetite stimulants and may be associated with hepatotoxicity
- Debilitated horses (improvement in weight, haircoat, or general physical condition) · 1.1 mg/kg IM; may repeat in 3 week intervals · IM · q3w · Most horses will respond with one or two treatments. ARCI UCGFS Class 4 Drug.
- Debilitated horses · 1 mg/kg IM; repeated at 3 week intervals · IM · q3w · ARCI UCGFS Class 4 Drug.
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
禁忌
- Stallions intended for reproduction
- Pregnant mares (Category X - risk of fetal masculinization)
- Non-pregnant mares intended for reproduction
- Horses intended for food purposes
- Patients with hepatic dysfunction
- Patients with hypercalcemia
- Patients with a history of myocardial infarction
- Patients with pituitary insufficiency
- Patients with prostate carcinoma or benign prostatic hypertrophy
有害事象
- Androgenic effects (over-aggressiveness)
- Detrimental effects on testis size and sperm production in males
- Altered sexual behavior, shortened estrus, and reduced pregnancy rates in females
- Clitoral enlargement in females
- Hepatotoxicity
- Sodium and water retention
薬物相互作用
- Anticoagulants (e.g., warfarin) · Anabolic agents may potentiate the effects of anticoagulants; monitoring of INR and dosage adjustment are recommended.
- Corticosteroids / ACTH · May enhance the edema that can be associated with ACTH or adrenal steroid therapy.
- Insulin · May decrease blood glucose and decrease insulin requirements; diabetic patients may need dosage adjustments.
モニタリング
- Androgenic side effects (e.g., aggression, behavioral changes)
- Fluid and electrolyte status, if indicated
- Liver function tests, if indicated
- Red blood cell count and indices, if indicated
- Weight and appetite
過量投与
Sodium and water retention can occur after overdosage of anabolic steroids. It is suggested to treat supportively and monitor liver function should an inadvertent overdose be administered.
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。