格隆溴銨
格隆溴銨是一種合成的季銨類抗毒蕈鹼藥物，主要用作麻醉前給藥、治療心搏過緩及減少唾液分泌。與阿托品不同，它不易穿透血腦屏障，因此中樞神經系統副作用較少。
作用機制: Glycopyrrolate acts as a competitive antagonist of **acetylcholine** at postganglionic **muscarinic receptors** (M1, M2, M3). **Acetylcholine** → Blocked at **Muscarinic Receptors** → Decreased parasympathetic tone. This blockade leads to: - **Heart:** Vagolytic effect → Increased heart rate (tachycardia). - **Secretions:** Antisialagogue effect → Profound reduction in salivary, tracheobronchial, and pharyngeal secretions. - **GI/Urinary:** Decreased smooth muscle motility and tone. - **Eye:** Mydriasis (pupil dilation) and cycloplegia.
各物種劑量
- As an adjunct to anesthesia · 0.011 mg/kg · IM · For maximum effect give 15 minutes prior to anesthetic administration
- For bradyarrhythmias · 0.005-0.01 mg/kg IV or IM, 0.01-0.02 mg/kg SC · IV, IM, SC
- Associated with anesthesia · 0.005-0.01 mg/kg · IV
- As a premed · 0.01 mg/kg · SC or IM
- As a premed · 0.01-0.02 mg/kg · IM or IV
- For treatment of bradyarrhythmias · 0.005-0.01 mg/kg (5-10 micrograms/kg) · IV · Note: ARCI UCGFS Class 3 Drug
- As a bronchodilator · 2-3 mg · IM · two to three times daily · Dose for a 450 kg animal
- To control muscarinic adverse effects associated with imidocarb therapy · 0.0025 mg/kg · IV
- For prevention of bradycardia and to decrease airway and salivary secretions (Rabbits) · 0.01-0.1 mg/kg IM, SC; 0.01 mg/kg IV · IM, SC, IV
- As adjunct to anesthesia (Rabbits) · 0.01-0.02 mg/kg · SC · as needed
- As a preanesthetic (Rodents) · 0.01-0.02 mg/kg · SC or IM
- As a preanesthetic (Rabbits) · 0.01-0.1 mg/kg · IM or SC
- As part of an injectable anesthesia protocol in rabbits · 0.01 mg/kg · IM · Given with acepromazine (0.2 mg/kg) and oxymorphone (0.1 mg/kg)
- As an adjunct to anesthesia · 0.011 mg/kg · IV, IM, or SC
- As an adjunct to anesthesia · 0.01-0.02 mg/kg · SC or IM
- For adjunctive therapy of bradyarrhythmias · 0.011 mg/kg · IV or IM
- Associated with anesthesia · 0.005-0.01 mg/kg · IV
- For bradyarrhythmias (sinus bradycardia, high-grade 2nd-degree and 3rd-degree AV block) produced by increased vagal tone · 0.05-0.1 mg/kg · IV
- To reduce hypersialism · 0.01 mg/kg · SC · as needed
- For bradycardia (prolonged or profound) associated with anesthesia · 0.01 mg/kg · IM, IV or IC (intracoelemic)
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
- Narrow angle glaucoma
- Tachycardias
- Gastrointestinal ileus
- Urinary obstruction
- Hypersensitivity to the drug
- Pregnancy (per some manufacturer labels)
不良反應
- Dry secretions (xerostomia)
- Initial bradycardia followed by tachycardia
- Decreased gastrointestinal motility (risk of ileus)
- Decreased urinary tract motility
- Mydriasis and cycloplegia
藥物相互作用
- Amantadine · May enhance the activity or toxicity of glycopyrrolate.
- Antihistamines (e.g., diphenhydramine) · May enhance anticholinergic activity or toxicity.
- Meperidine · May enhance anticholinergic activity or toxicity.
- Phenothiazines · May enhance anticholinergic activity or toxicity.
- Tricyclic Antidepressants (e.g., amitriptyline, clomipramine) · May enhance anticholinergic activity or toxicity.
- Amitraz · May aggravate signs seen with amitraz toxicity, leading to hypertension and further inhibition of peristalsis.
- Antacids · May decrease PO absorption; give oral glycopyrrolate at least 1 hour prior to oral antacids.
- Corticosteroids (long-term use) · May increase intraocular pressure when used concurrently.
- Digoxin (slow-dissolving) · May increase serum digoxin levels; use regular digoxin tablets or oral liquid.
- Ketoconazole · Increased gastric pH may decrease GI absorption; administer 2 hours after ketoconazole.
- Metoclopramide · Glycopyrrolate may antagonize the prokinetic actions of metoclopramide.
監測
- Heart rate and rhythm
- Respiratory rate and effort
- Gastrointestinal motility (auscultation for bowel sounds)
- Salivary and respiratory secretions
過量
In dogs, the LD50 is reported to be 25 mg/kg IV. In cats, the LD50 after IM injection is 283 mg/kg. Because of its quaternary structure, **minimal CNS effects** would be expected after an overdose compared to atropine. Overdose may present with severe anticholinergic signs (extreme tachycardia, mydriasis, dry mucous membranes, ileus). Treatment is generally supportive.
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。