育亨賓
育亨賓是一種吲哚烷基胺生物鹼及特異性α2-腎上腺素受體拮抗劑。在獸醫學中主要用於逆轉α2-致效劑（特別是甲苯噻嗪 xylazine）的鎮靜與心血管作用。此外，它也是雙甲脒 (amitraz) 中毒的有效解毒劑，甚至可在使用雙甲脒前作為預防。雖然現代臨床上逆轉右美托咪啶 (dexmedetomidine) 多改用阿替美唑 (atipamezole)，育亨賓仍是重要的急救與逆轉藥物。
作用機制: Yohimbine competitively blocks central and peripheral **presynaptic alpha-2 adrenergic receptors**. - **Mechanism:** By blocking these autoreceptors, yohimbine prevents the negative feedback loop that normally inhibits neurotransmitter release → **increases synaptic norepinephrine** release → enhances sympathetic outflow. - **Systemic Effects:** This surge in sympathetic tone results in increased heart rate, elevated blood pressure, CNS stimulation, and antidiuresis, effectively counteracting the profound sedation, bradycardia, and hypotension induced by alpha-2 agonists.
各物種劑量
- Xylazine reversal (Llamas/Camelids) · 0.25 mg/kg IV or IM · IV/IM · once · Dosing specifically reported for Llamas.
- Xylazine reversal · 0.125 mg/kg IV · IV · once
- Xylazine reversal (Routine/Emergency) · IM administration preferred for routine; 0.1 mg/kg IV for emergency · IM/IV · once · IM preferred to decrease CNS/CV risks. Wait 30-45 min post-IM or 15-30 min post-IV xylazine to allow ketamine/Telazol to resolve before reversing.
- Xylazine reversal · 0.075 mg/kg IV · IV · once · ARCI UCGFS Class 2 Drug.
- Alpha2-adrenergic agonist reversal (e.g., xylazine) · 0.1 mg/kg IV · IV · once
- Xylazine reversal (Rabbits) · 0.2 mg/kg IV · IV · as needed · Also partially antagonizes ketamine and acepromazine.
- Xylazine reversal (Mice/Rats) · 0.2 mg/kg IP · IP · as needed · Also partially antagonizes ketamine and acepromazine.
- Xylazine reversal · 0.11 mg/kg IV slowly OR 0.1 mg/kg IV · IV · once
- Medetomidine reversal · 0.11 mg/kg IV · IV · once
- Amitraz toxicity reversal (centrally mediated bradycardia/hypotension) · 0.1 mg/kg IV · IV · repeat as necessary
- Amitraz toxicity (demodicosis treatment) · 0.11 mg/kg IV or 0.25 mg/kg IM (with atipamezole 50 mcg/kg IM) · IV/IM · once · Used to treat or prevent acute toxicity episodes.
- Prevention of side effects from amitraz dips · 0.1 mg/kg IV · IV · once · May give prior to, or after bathing.
- Antiemetic · 0.25-0.5 mg/kg SC or IM · SC/IM · q12h
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
- Hypersensitivity to yohimbine
- Renal disease (extrapolated from human medicine)
- Patients with active seizure disorders
不良反應
- Transient apprehension or anxiety
- CNS excitement
- Muscle tremors
- Hypersalivation
- Increased respiratory rate (panting)
- Hyperemic (red) mucous membranes
- Tachycardia
藥物相互作用
- Tricyclic Antidepressants · May cause severe hypertension; concurrent use is not recommended.
- Other Alpha-2 Antagonists · Additive antagonistic effects; use with caution.
- CNS Stimulants · Additive CNS stimulation and increased risk of seizures or severe agitation.
監測
- CNS status (arousal level, signs of excitement or apprehension)
- Cardiac rate and rhythm
- Blood pressure (if indicated and practical)
- Respiratory rate and effort
過量
Overdoses can cause significant CNS and cardiovascular overstimulation. - **Experimental Data:** Dogs receiving 0.55 mg/kg (5 times the recommended dose) exhibited clinical signs of transient seizures and muscle tremors. - **Clinical Reports (APCC):** Reported findings in dogs include diarrhea, disorientation, hyperactivity, panting, tachycardia, and hypersalivation. - **Treatment:** Primarily supportive and symptomatic. Avoid further CNS stimulation and manage seizures if they occur.
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。