德舍瑞林
**醋酸德舍瑞林 (Deslorelin acetate)** 是一種強效的合成促性腺素釋放素 (GnRH) 類似物。在獸醫學中，根據劑型和暴露時間的不同，它被用於兩個截然不同的目的： * **短期使用（誘導排卵）：** 在母馬中，短效注射懸浮液或可移除的植入劑被用來誘導並精確控制排卵時間，以提高繁殖成功率。 * **長期使用（藥物閹割/避孕）：** 緩釋植入劑提供持續的 GnRH 刺激，最終會抑制生殖軸。這可用於公狗的可逆性避孕，以及標示外用於治療良性前列腺肥大 (BPH) 和已切除卵巢母狗的尿失禁。 > **臨床要點：** 雖然並非所有地區都有明確標示，但德舍瑞林植入劑 (Suprelorin) 被廣泛認為是治療**雪貂腎上腺疾病**的黃金標準，也常被標示外用於特寵和動物園動物的繁殖控制。
作用機制: Deslorelin acts as an agonist at **GnRH receptors** in the anterior pituitary gland. Its clinical effect depends entirely on the duration of administration: * **Acute Administration (Flare Effect):** Initial binding to GnRH receptors stimulates a rapid surge in the release of **luteinizing hormone (LH)** and **follicle-stimulating hormone (FSH)**. * *Pathway:* Deslorelin → Pituitary GnRH receptors → ↑ LH/FSH surge → **Induction of ovulation** (in mares with mature follicles >30 mm). * **Continuous Administration (Downregulation):** When provided as a sustained-release implant, the continuous presence of the GnRH analog overstimulates the receptors. * *Pathway:* Continuous deslorelin → **Internalization and downregulation of GnRH receptors** → Profound suppression of LH and FSH secretion → Decreased production of gonadal steroids (testosterone/estrogen) → **Reversible chemical castration/contraception**.
各物種劑量
- Induction of ovulation (follicle 30-40 mm in diameter) · 1.8 mg (1 mL) · IM · Once · Single dose · Administer in the neck. Shake vial well before drawing into syringe.
- Induction of ovulation (follicle >30 mm in diameter) · 1 implant (2.1 mg) · SC · Once · Remove after 48h · Implant SC in the neck. Remove after approx 48 hours to prevent prolonged interovulatory interval. Alternative: Infuse 1 mL lidocaine into vulvar edge, insert implant beneath epithelium. Squeeze out after ovulation.
- Contraceptive in male dogs · 4.7 mg implant SC every 6 months OR 9.4 mg implant SC every 12 months · SC · q6mo or q12mo · Continuous · Implant in loose skin between lower neck and lumbar area; avoid implanting into fat. Pregnant women should not administer the implant.
- Temporary chemical castration · 1 implant (4.7 mg or 9.4 mg) per male dog · SC · repeat after 6 or 12 months · 6 to 12 months depending on implant size · Dogs <10 kg may take up to 18 months to recover testosterone. Separation from females in heat required for first 6 weeks.
- Temporary chemical castration · 1 implant (4.7 mg) per male cat · SC · once · 2-4 years · Causes chemical castration for 2-4 years in tom cats.
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
- Known hypersensitivity to deslorelin
- Horses intended for human consumption
- Intravenous (IV) administration
- Administration by pregnant women (implants)
不良反應
- Local swelling, pain, and elevated skin temperature at the injection/implant site (usually resolves within 5 days)
- Prolonged interovulatory period in mares if the 2.1 mg implant is not removed
- Initial transient increase in sexual behavior or clinical signs (flare effect) before suppression occurs (with long-acting implants)
監測
- Follicle size via ultrasound or rectal palpation (mares)
- Injection/implant site for severe swelling or reaction
- Resolution of clinical signs or reduction in testicular size (when used for contraception in dogs)
過量
In mares receiving a single IM injection at 10X the recommended dose (18 mg), moderate tremors and hives were observed 6 hours after injection in one out of eight horses. If an inadvertent additional implant is administered, it should be removed upon detection if within 96 hours of implantation.
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。