II. Pharmacology
- Tertiary ammonium alkaloid ester of tropic acid
- Naturally occurs in plant sources
- Atropa belladonna (Deadly nightshade)
- Datura stramonium (Jimsonweed, Thorn apple)
- Described as Belladonna (beautiful woman) alkaloid
- Women of past used Atropine to dilate pupils
- Mydriasis was perceived as more attractive
- Related isomer to Scopolamine (Hyoscine)
III. Mechanism
- Antimuscarinic Cholinoceptor blocking drug
- Causes parasympathetic blockade (parasympatholytic)
- Inhibits vagal nerve activity (vagolytic)
- Enhances Sinus node automaticity
- Enhances Atrioventricular Node (AV) conduction
IV. Indications
-
Symptomatic Bradycardia associated with
- Poor perfusion
- Hypotension
- Relative Bradycardia
- Prevent vagally mediated Bradycardia with intubation
- Symptomatic Bradycardia with AV Block
-
Asystole or Pulseless Electrical Activity
- No evidence that survival is improved with Atropine
- Asystole is nearly always fatal despite intervention
- Nerve Agent Exposure
V. Dosing: Severe Bradycardia or CPR - Child
- IV Dose
- Dose: 0.02 mg/kg IV or IO every 5 minutes for up to 2 to 3 doses
- Minimum Dose: 0.1 mg
- Maximum Dose
- Child: 0.5 mg
- Teen: 1.0 mg
- Endotracheal Dose (IV/IO is preferred)
- Dose: 2-3x IV dose (0.06 mg/kg) diluted in 3-5cc NS
- Follow dose with several positive pressure breaths
VI. Dosing: Severe Bradycardia or CPR - Adult
-
Bradycardia
- Dose: 0.5-1.0 mg IV
- May repeat every 3-5 min to max total dose of 0.04 mg/kg or 3 mg
-
Asystole or Bradycardic Pulseless Electrical Activity
- Dose: 1 mg IV
- Consider giving entire 0.04 mg/kg at start)
- May repeat q3-5 min to max total dose of 0.04 mg/kg
- Endotracheal Dosing (IV/IO is preferred)
- Dose: 1-2 mg per dose
- Dilute to 10 ml with sterile water or saline
VII. Dosing: Nerve Agent Exposure
- See Nerve Agent Exposure
- Adjunct to Pralidoxime chloride (2-PAMCl)
- Atropine (Preservative-free) is indicated for muscarinic effects (bronchorrhea, bronchospasm, Bradycardia)
- Goal: Drying of secretions (will not reverse neuromuscular effects, Muscle Weakness or Respiratory Failure)
- Repeat doses until Shortness of Breath and Wheezing resolve and excess secretions reduce
- Adult
- Dose 1-2 mg slow IV push (up to 2-5 mg IV) every 15 minutes as needed
- May be given as often as every 3-5 minutes, doubling dose
- Most effective for pulmonary symptoms in adults
- Very high doses (e.g. 40 mg) may be needed
- Autoinjectors contain 2 mg Atropine
- Child <12 years
- Dose 0.015 to 0.05 mg/kg slow IV push (up to 0.1 mg/kg) every 15 minutes as needed
- May be given as often as every 3-5 minutes, doubling dose
- Most effective for CNS symptoms in children
- Pediatric autoinjectors are available
- Use 0.25 mg pen for weight <7 kg, 0.5 mg pen if 7 to 18 kg and 1 mg if 18 to 41 kg
- Use adult dose or adult autoinjector (2 mg) if weight >41 kg
- Taper dose, and discontinue by 24 hours
- Atropine may be continued as drip at 0.5 to 2.4 mg/kg/h
- Indicated for persistent symptoms (up to 48 hours may be needed in severe cases)
VIII. Precautions
- Avoid repeat dosing if possible
- Increases myocardial oxygen demand
- Atropine may provoke Ischemic Heart Disease
- Consider external pacing if repeat dosing needed
- Avoid dosing Atropine below recommended dose
- Causes paradoxical Bradycardia
- May precipitate Ventricular Fibrillation
IX. Adverse effects
- Rebound Tachycardia
- Paradoxical Bradycardia (if low dose Atropine used)
- Pupil dilatation (Mydriasis)
- Paradoxical rate slowing
- Arrhythmia (especially in Coronary Artery Disease)
- Anticholinergic Toxicity with overdosage
- Decreased Sweating and secretions
- Mild sedation to Delirium
X. Resources
Images: Related links to external sites (from Bing)
Related Studies
| atropine (on 6/21/2023 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| ATROPINE 1% EYE DROPS | Generic | $10.08 per ml |
Ontology: Atropine (C0004259)
| Definition (MSH) | An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine. |
| Definition (NCI) | A synthetically-derived form of the endogenous alkaloid isolated from the plant Atropa belladonna. Atropine functions as a sympathetic, competitive antagonist of muscarinic cholinergic receptors, thereby abolishing the effects of parasympathetic stimulation. This agent may induce tachycardia, inhibit secretions, and relax smooth muscles. (NCI04) |
| Definition (CSP) | anticholinergic alkaloid originally from Atropa belladonna; used as an antispasmodic to relax smooth muscles, to increase heart rate by blocking the vagus nerve, as an antidote for various toxic and anticholinesterase agents, and as an antisecretory, mydriatic, and cycloplegic. |
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | D001285 |
| SnomedCT | 372832002, 73949004 |
| LNC | LP14891-3, MTHU002117 |
| English | Atropine, dl-Hyoscyamine, Benzeneacetic acid, alpha-(hydroxymethyl)- 8-methyl-8-azabicyclo(3.2.1)oct-3-yl ester endo-(+-)-, dl-Tropyl Tropate, endo-(+/-)-alpha-(Hydroxymethyl)benzeneacetic Acid 8-methyl-8-azabicyclo[3.2.1]oct-3-yl Ester, atropine (medication), Atropine [Chemical/Ingredient], ATROPINE, atropine [chemical substance], atropine, Daturine, Dl-hyoscyamine, Atropine (product), Atropine (substance), Hyoscyamine (dl-) |
| Swedish | Atropin |
| Czech | atropin |
| Finnish | Atropiini |
| Russian | ATROPIN, АТРОПИН |
| Japanese | ヒオスシアミン, アトロピン |
| Polish | Atropina |
| Spanish | DI-hiosciamina, atropina (producto), atropina (sustancia), atropina, daturina, Atropina |
| French | Atropine |
| German | Atropin |
| Italian | Atropina |
| Portuguese | Atropina |
