Atropine Sulfate
Related Subjects: Atropine
|Acute Anaphylaxis
|Basic Life Support
|Advanced Life Support
|Adrenaline/Epinephrine
|Acute Hypotension
|Cardiogenic shock
|Distributive Shock
|Hypovolaemic or Haemorrhagic Shock
|Obstructive Shock
|Septic Shock and Sepsis
|Shock (General Assessment)
|Toxic Shock Syndrome
- ❤️ Used in emergency settings for symptomatic bradycardia (not part of current cardiac arrest protocol).
- 🌿 Derived from the alkaloid in deadly nightshade (Atropa belladonna).
- 👁️ Historically used cosmetically to dilate pupils (“bella donna” effect).
⚙️ Mode of Action
- 🚫 Competitive muscarinic acetylcholine receptor antagonist.
- 🧠 Blocks parasympathetic stimulation → ↑ heart rate, ↓ secretions, smooth muscle relaxation.
⚠️ Cautions
- ⚠️ Myasthenia gravis (may worsen weakness).
- 🚫 GI ileus or urinary retention / BPH (risk of obstruction).
- ⚠️ Avoid in cardiac transplant – denervated hearts may be hypersensitive.
- ⬆️ Caution in Down’s syndrome, reflux disease (GORD).
🎯 Indications / Dose
- ❤️ Severe bradycardia: 500 mcg (0.5 mg) IV bolus.
Repeat every 3–5 minutes to a max of 3 mg.
If ineffective → consider pacing.
- ☠️ Organophosphate poisoning: 2–3 mg IV initially; often requires repeated or escalating doses depending on symptoms (salivation, bronchospasm, bradycardia).
📊 Dose Notes (check BNF / datasheet)
- ➡️ Bradycardia: 0.5 mg IV q3–5min (max 3 mg).
- ➡️ OP toxicity: start 2–3 mg IV; may need higher repeated dosing until secretions dry and heart rate stabilises.
🔄 Interactions
- 📌 No major interactions, but additive anticholinergic effects if combined with other antimuscarinics (e.g. tricyclics, antihistamines).
⛔ Contraindications
- 🚫 Cardiac transplant patients (risk of severe tachyarrhythmia from denervation hypersensitivity).
⚠️ Side Effects
- 💧 Reduced secretions, dry warm skin.
- 👁️ Pupil dilation (mydriasis), blurred vision, photophobia.
- 🧠 Delirium, confusion (especially in elderly).
- ❤️ Increased heart rate; high doses → tachyarrhythmias (VF, VT, SVT).
- 🫁 Bronchodilation.
- 🚻 Urinary retention, constipation.
📚 References
