硫酸アトロピン

動物種別の用量

投与経路

禁忌

• Narrow-angle glaucoma
• Synechiae (adhesions) between the iris and lens
• Hypersensitivity to anticholinergic drugs
• Tachycardias secondary to thyrotoxicosis or cardiac insufficiency
• Myocardial ischemia
• Unstable cardiac status during acute hemorrhage
• GI obstructive disease or paralytic ileus
• Severe ulcerative colitis
• Obstructive uropathy
• Myasthenia gravis (unless used to reverse adverse muscarinic effects secondary to therapy)

有害事象

• Dry mouth (xerostomia)
• Dysphagia
• Constipation
• Vomiting
• Thirst
• Urinary retention or hesitancy
• CNS stimulation, drowsiness, ataxia, seizures, respiratory depression
• Blurred vision, pupil dilation (mydriasis), cycloplegia, photophobia
• Sinus tachycardia (at higher doses)
• Paradoxical bradycardia (initially or at very low doses)
• Hypertension or hypotension
• Arrhythmias (ectopic complexes)
• Decreased gut motility (can induce colic in horses or rumen stasis in cattle)

薬物相互作用

• Amantadine · May enhance the activity or toxicity of atropine
• Anticholinergic agents (other) · May enhance the activity or toxicity of atropine
• Antihistamines (e.g., diphenhydramine) · May enhance the activity or toxicity of atropine
• Disopyramide · May enhance the activity or toxicity of atropine
• Meperidine · May enhance the activity or toxicity of atropine
• Phenothiazines · May enhance the activity or toxicity of atropine; do not use in atropine overdose
• Procainamide · May enhance the activity or toxicity of atropine
• Primidone · May enhance the activity or toxicity of atropine
• Tricyclic antidepressants (e.g., amitriptyline, clomipramine) · May enhance the activity or toxicity of atropine
• Alpha-2 agonists (e.g., dexmedetomidine, medetomidine) · Use with alpha-2 blockers may significantly increase arterial blood pressure, heart rates, and the incidence of arrhythmias. Concurrent use is controversial.
• Amitraz · Atropine may aggravate signs of amitraz toxicity, leading to hypertension and further inhibition of peristalsis
• Antacids · May decrease PO atropine absorption; give oral atropine at least 1 hour prior to oral antacids

モニタリング

• Heart rate and rhythm
• Thirst and appetite
• Urination and defecation capability
• Mouth and secretions dryness
• Pupillary dilation (mydriasis)

過量投与

**Signs of Toxicity:** Extensions of pharmacologic effects: severe dry mouth, dysphagia, extreme thirst, vomiting, urinary retention, CNS signs (extreme agitation, seizures, ataxia, respiratory depression), severe tachycardia, arrhythmias, and circulatory failure. **Treatment:** - **Decontamination**: If recent oral ingestion, empty gut contents and administer activated charcoal and saline cathartics. - **Supportive Care**: Treat clinical signs supportively and symptomatically. Fluid therapy and standard treatments for shock may be instituted. - **Contraindications**: Do NOT use phenothiazines as they may contribute to anticholinergic effects. - **Antidote (Physostigmine)**: Controversial. Reserve for extreme agitation/risk of injury or severe/life-threatening supraventricular and sinus tachycardias. - *Human dose*: 2 mg IV slowly. - *Pediatric/Small Animal dose*: 0.02 mg/kg slow IV (repeat q10 minutes until reversal). - *Note*: Physostigmine adverse effects (bronchoconstriction, bradycardia, seizures) may be treated with small doses of IV atropine.