戈那瑞林
戈那瑞林是一種合成的**下丘腦荷爾蒙**（GnRH類似物），在獸醫學中主要用於治療生殖系統疾病，如乳牛的卵巢濾泡囊腫。 主要特點： - **作用時間極短**（僅數分鐘）。 - 在小動物中常以仿單標示外（off-label）方式用於診斷（例如區分已去勢與未去勢動物、確認隱睪）以及誘導發情或排卵。 - 用於經濟動物時，**無須停藥期**（不影響屠宰或泌乳）。 - 安全性極高，幾乎無不良反應報告。
作用機制: Gonadorelin acts as a synthetic **GnRH** (Gonadotropin-Releasing Hormone) → binds to receptors on the anterior pituitary gland → stimulates a surge-like release of **FSH** (Follicle Stimulating Hormone) and **LH** (Luteinizing Hormone). - In females (cows, ewes, cats), this LH surge can induce ovulation or luteinization of cystic follicles. - In males, it stimulates testosterone release, which is useful for diagnostic stimulation testing. - Note: A constant infusion initially stimulates LH/FSH release, but eventually causes receptor downregulation and levels return to baseline.
各物種劑量
- To induce ovulation outside of the breeding season · 100 micrograms injected daily · Injection · q24h · 4-5 days
- To induce ovulation outside of the breeding season in the doe · 100 micrograms injected daily · Injection · q24h · 4-5 days
- To stimulate ovulation after mating · 25 micrograms IM after mating · IM · Once
- For infertility, reduced libido, testis descent in male cats · 1 microgram/kg every 2-3 days · IM · q48-72h
- To detect ovarian remnants in queens after ovariohysterectomy · 25 micrograms per cat · IM · Once · Progesterone level (>1 ng/mL) 1-2 weeks post treatment verifies presence of ovarian tissue.
- To induce ovulation · 20 micrograms IM · IM · Once · Repeat in one week as necessary · Most effective 14 days after onset of estrus.
- To treat ovarian cysts in cattle · 100 micrograms IM or IV · IM/IV · Once
- To treat ovarian cysts in cattle · 100 micrograms IM per cow · IM · Once
- GnRH stimulation test to differentiate castration from cryptorchidism · 50 micrograms IM (Take pre-sample, give injection, 2-3 hours later take post-injection sample) · IM · Once · Castrated dogs have testosterone concentrations <0.1 ng/mL and GnRH does not stimulate.
- GnRH stimulation test to determine if dog has retained testicle · 2.5 micrograms/kg IM (if very small dog use 25 micrograms total dose instead) · IM · Once · Take pre-sample, give injection, take second sample in 60-90 minutes.
- To aid in the descent of cryptorchid testes · 50-100 micrograms SC or IV · SC/IV · Once · Repeat in 4-6 days if no response
- To increase libido in male dogs · 50-100 micrograms IM weekly · IM · Weekly · 4 to 6 weeks · Anecdotal use.
- For cystic ovarian disease in bitches · 3.3 micrograms/kg IM once daily · IM · q24h · 3 days · Elevated progesterone (>2 ng/mL) 1-2 weeks post treatment verifies success.
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
- None noted on the label
不良反應
- None reported
- Hypersensitivity reactions are highly unlikely with synthetic preparations
監測
- Clinical efficacy (e.g., resolution of cystic ovaries, induction of estrus)
- Serum progesterone levels (for ovarian remnant or cystic ovary verification)
- Serum testosterone levels (for cryptorchidism/castration testing)
過量
In doses of up to 120 micrograms/kg, no untoward effects were noted in several species of test animals. Gonadorelin is unlikely to cause significant adverse effects after inadvertent overdosage.
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。