Medical Editor: John P. Cunha, DO, FACOEP
Atropine Sulfate Injection is an antimuscarinic agent used to treat bradycardia (low heart rate), reduce salivation and bronchial secretions before surgery, as an antidote for overdose of cholinergic drugs or mushroom poisoning. Common side effects of atropine sulfate include:
- dry mouth,
- blurred vision,
- sensitivity to light,
- lack of sweating,
- loss of balance,
- hypersensitivity reactions (such as skin rash), and
- rapid heartbeat (tachycardia).
Initial single doses of Atropine Sulfate in adults vary from 0.5 mg to 1 mg (5 - 10 mL of the 0.1 mg/mL solution) for antisialagogue and other antivagal effects, to 2 to 3 mg (20 - 30 mL of the 0.1 mg/mL solution) as an antidote for organophosporous or muscarinic mushroom poisoning. Atropine Sulfate may interact with other drugs. Tell your doctor all medications and supplements you use. During pregnancy, Atropine Sulfate should be used only if prescribed. Consult your doctor before breastfeeding.
Our Atropine Sulfate Injection Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
The following serious adverse reactions are described elsewhere in the labeling:
- Cardiovascular Risks [see WARNINGS AND PRECAUTIONS]
- Heat Injury [see WARNINGS AND PRECAUTIONS]
- Acute Glaucoma [see WARNINGS AND PRECAUTIONS]
- Urinary Retention [see WARNINGS AND PRECAUTIONS]
- Pyloric Stenosis [see WARNINGS AND PRECAUTIONS]
- Exacerbation of Chronic Lung Disease [see WARNINGS AND PRECAUTIONS]
- Hypersensitivity [see WARNINGS AND PRECAUTIONS]
The following adverse reactions associated with the use of atropine were identified in the literature. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Injection Site Reactions
Mild to moderate pain may be experienced at the site of injection.
Adverse Reactions At Recommended Dosages
The major and most common side effects of atropine can be attributed to its antimuscarinic action. These include dryness of the mouth, blurred vision, dry eyes, photophobia, confusion, headache, dizziness, fatigue, tachycardia, palpitations, flushing, urinary hesitance or retention, constipation, abdominal pain, abdominal distention, nausea, vomiting, loss of libido, and impotency. Anhidrosis may produce heat intolerance and impairment of temperature regulation especially in a hot environment.
Hypersensitivity reactions will occasionally occur with atropine; these are usually seen as skin rashes, on occasion progressing to exfoliation. Anaphylactic reactions have occurred.
Additional Adverse Reactions To Atropine By Organ System
The following adverse reactions were reported in published literature for atropine in both adults and pediatric patients:
Sinus tachycardia, supraventricular tachycardia, junctional tachycardia, ventricular tachycardia, bradycardia, palpitations, ventricular arrhythmia, ventricular flutter, ventricular fibrillation, atrial arrhythmia, atrial fibrillation, atrial ectopic beats, ventricular premature contractions, bigeminal beats, trigeminal beats, nodal extrasystole, ventricular extrasystole, supraventricular extrasystole, asystole, cardiac syncope, prolongation of sinus node recovery time, cardiac dilation, left ventricular failure, myocardial infarction, intermittent nodal rhythm (no P wave), prolonged P wave, shortened PR segment, R on T phenomenon, shortened RT duration, widening and flattening of QRS complex, prolonged QT interval, flattening of T wave, repolarization abnormalities, altered ST-T waves, retrograde conduction, transient AV dissociation, increased blood pressure, decreased blood pressure, labile blood pressure, weak or impalpable peripheral pulses.
Mydriasis, pupils poorly reactive to light, decreased contrast sensitivity, decreased visual acuity, decreased accommodation, cycloplegia, strabismus, heterophoria, cyclophoria, acute angle closure glaucoma, conjunctivitis, keratoconjunctivitis sicca, blindness, tearing, dry conjunctiva, irritated eyes, crusting of eyelid, blepharitis.
Paralytic ileus, decreased bowel sounds, delayed gastric emptying, decreased food absorption, dysphagia.
Hyperpyrexia, lethargy, somnolence, chest pain, excessive thirst, weakness, syncope, insomnia, tongue chewing, dehydration, feeling hot.
Leukocytosis, hyponatremia, elevated BUN, elevated hemoglobin, elevated erythrocytes, low hemoglobin, hypoglycemia, hyperglycemia, hypokalemia, increase in photic stimulation on EEG, signs of drowsiness on EEG, runs of alpha waves on EEG, alpha waves (EEG) blocked upon opening eyes.
Failure to feed.
Central Nervous System
Ataxia, hallucinations (visual or aural), seizures (generally tonic-clonic), abnormal movements, coma, stupor, amnesia, diminished tendon reflexes, hyperreflexia, muscle twitching, opisthotnos, Babinski's reflex/Chaddock's reflex, hypertonia, dysmetria, muscle clonus, sensation of intoxication, difficulty concentrating, vertigo, dysarthria.
Agitation, restlessness, delirium, paranoia, anxiety, mental disorders, mania, withdrawn behavior, behavior changes.
Difficulty in micturation, urine urgency, distended urinary bladder, bed-wetting.
Tachypnea, slow respirations, shallow respirations, breathing difficulty, labored respirations, inspiratory stridor, laryngitis, laryngospasm, pulmonary edema, respiratory failure, subcostal recession.
Dry mucous membranes, dry warm skin, oral lesions, dermatitis, petechiae, rash, macular rash, papular rash, maculopapular rash, scarlatiniform rash, erythematous rash, sweating/moist skin, cold skin, cyanosed skin, salivation.
Adverse Reactions Caused By Inadvertent Injection
Administering additional 2 mg Atropine autoinjectors by mistake in the absence of actual nerve agent or insecticide poisoning may cause an overdose of atropine which could result in temporary incapacitation (inability to walk properly, see clearly or think clearly for several or more hours). Patients with cardiac disease may be at risk for serious adverse events, including death.
Adverse Reactions Observed In Pediatric Patients After Inappropriate Administration Of Atropine
Amitai et al. (JAMA 1990) evaluated the safety of an atropine autoinjector in a case series of 240 children who received the atropine inappropriately (i.e., no nerve agent exposure) during the 1990 Gulf War Period. Overall, severity of atropinization followed a nonlinear correlation with dose. Estimated doses up to 0.045 mg/kg produced no signs of atropinization. Estimated doses between 0.045 mg/kg to 0.175 mg/kg and even greater than 0.175 mg/kg were associated with mild and severe effects respectively. Actual dosage received by children may have been considerably lower than estimated since incomplete injection in many cases was suspected. Regardless, adverse events reported were generally mild and self-limited. Few children required hospitalization. Adverse reactions reported were dilated pupils (43%), tachycardia (39%), dry membranes (35%), flushed skin (20%), temperature 37.8° C or 100° F (4%), and neurologic abnormalities (5%). There was also local pain and swelling. In patients with electrocardiograms, 22 of 91 (24%) children had severe tachycardia of 160-190 bpm. Neurologic abnormalities consisted of irritability, agitation, confusion, lethargy, and ataxia. Atropine 2mg is only approved for pediatric patients weighing more than 41kg at the recommended dosing.
Read the entire FDA prescribing information for Atropine (Atropine)
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