Drug Guide
Atropine Sulfate
Classification
Therapeutic: Anticholinergic agent
Pharmacological: Antimuscarinic
FDA Approved Indications
- Bradycardia (including temporary control of heart rate during surgery)
- Preoperative medication to reduce salivary and respiratory secretions
- Poisoning or overdose of cholinergic agents
Mechanism of Action
Atropine competitively inhibits the action of acetylcholine at parasympathetic sites in smooth muscle, secretory glands, and the CNS, leading to increased heart rate, decreased salivary secretions, and reduced motility.
Dosage and Administration
Adult: 0.5 mg IV every 3-5 minutes as needed; maximum dose 3 mg.
Pediatric: 0.02 mg/kg IV every 3-5 minutes as needed; maximum total dose: 0.5 mg in children under 12, and higher doses in emergencies as directed by physician.
Geriatric: Start at lower dose; closely monitor due to increased sensitivity.
Renal Impairment: Use with caution; monitor for toxicity.
Hepatic Impairment: Use with caution; no specific adjustments established.
Pharmacokinetics
Absorption: Rapid IV, IM, and subcutaneous absorption.
Distribution: Widely distributed, crosses blood-brain barrier and placenta.
Metabolism: Partially metabolized in the liver.
Excretion: Excreted primarily in urine.
Half Life: 2-4 hours.
Contraindications
- Gastrointestinal or urinary tract obstruction
- Glaucoma (especially angle-closure glaucoma)
- Tachycardia caused by cardiac arrhythmias
Precautions
- Use with caution in patients with myasthenia gravis, ulcerative colitis, or cardiac arrhythmias; in elderly; in pregnancy and lactation; monitor for anticholinergic side effects.
Adverse Reactions - Common
- Dry mouth (Common)
- Blurred vision (Common)
- Urinary retention (Common)
- Tachycardia (Common)
Adverse Reactions - Serious
- Xerostomia leading to oral infections (Rare)
- Acute angle-closure glaucoma (Rare)
- Arrhythmias (Rare)
Drug-Drug Interactions
- Other anticholinergic agents, antihistamines, tricyclic antidepressants, phenothiazines, quinidine
Drug-Food Interactions
- None specifically noted but caution with alcohol and caffeine
Drug-Herb Interactions
- Potential additive anticholinergic effects with herbal remedies containing anticholinergic properties
Nursing Implications
Assessment: Monitor heart rate, blood pressure, respiratory status, and signs of anticholinergic toxicity.
Diagnoses:
- Ineffective airway clearance
- Risk for injury related to blurred vision or dizziness
Implementation: Administer IV slowly; have resuscitation equipment ready; observe for signs of toxicity.
Evaluation: Effectiveness assessed by stabilized heart rate and reduced secretions; adverse effects monitored.
Patient/Family Teaching
- Instruct to report rapid heartbeat, blurred vision, dry mouth, or difficulty urinating.
- Advise on safety precautions to avoid injury due to blurred vision or dizziness.
- Caution against operating heavy machinery until effects are known.
Special Considerations
Black Box Warnings:
- None specific
Genetic Factors: None established
Lab Test Interference: May interfere with certain lab tests for cholinergic activity.
Overdose Management
Signs/Symptoms: Tachycardia, dry mouth, hot and dry skin, dilated pupils, hallucinations, seizures.
Treatment: Administer activated charcoal if ingestion recent; provide supportive care, cooling measures for hyperthermia, and physostigmine as an antidote under physician supervision.
Storage and Handling
Storage: Store at controlled room temperature 20°C to 25°C (68°F to 77°F).
Stability: Stable under recommended storage conditions.