Class: Antimuscarinics/Antispasmodics
VA Class: AU350
CAS Number: 51-55-8
Brands: AtroPen, Sal-Tropine

Introduction

Antimuscarinic; a naturally occurring tertiary amine.

Uses for Atropine

Surgery

To inhibit salivation and excessive secretions of the respiratory tract (antisialogogue).^{b f} However, current surgical practice (e.g., using general anesthetics that do not stimulate salivary and tracheobronchial secretions) has reduced the need to control excessive respiratory secretions during surgery.^b

To prevent other cholinergic effects during surgery (e.g., cardiac arrhythmias, hypotension, bradycardia) secondary to visceral or ocular traction (resultant vagal stimulation), carotid sinus stimulation, or concomitant drugs (e.g., succinylcholine).^{b f}

To block adverse muscarinic effects of anticholinesterase agents that are used after surgery to terminate curarization.^{b f}

Ineffective for preventing acid-aspiration pneumonitis† during surgery.^b

CPR and Cardiac Arrhythmias

For its anticholinergic positive chronotropic effect in ACLS during CPR.^{b 106 108}

Treatment of symptomatic sinus bradycardia (e.g., that accompanied by hemodynamic compromise or by frequent ventricular ectopic beats).^{b 106 108} Reverses cholinergically mediated decreases in heart rate, systemic vascular resistance, and BP.^{b 106 108}

Treatment of symptomatic bradycardia caused by AV block at the nodal level or by vagal stimulation (e.g., induced by suctioning or endotracheal intubation).^{106 108} Do not rely on atropine for AV block at or below the His-Purkinje level (type II 2nd-degree AV block or 3rd-degree AV block, including 3rd-degree AV block accompanied by new wide QRS complexes); do not delay pacing, these patients require immediate pacing.¹⁰⁶

In children, for treatment of bradycardia secondary to increased vagal activity or primary AV block, however, only if manifestations of hemodynamic compromise persist despite support of adequate oxygenation and ventilation and chest compressions (if indicated); bradycardia may respond to these latter measures alone.^{b 106 108}

In neonates, lack of evidence of usefulness in the acute phase of CPR; therefore, current guidelines for ACLS no longer include recommendations for such use.^{b 106 108} Drugs rarely are needed during resuscitation of neonates; establishing adequate ventilation is most important measure to correct bradycardia.^{106 108}

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Treatment of asystole;^{b 106 108} efficacy in children is unclear.^{b 108}

Treatment of pulseless electrical activity (PEA) if PEA rate is slow.^{b 106 108}

Treatment of sustained bradycardia and hypotension associated with nitroglycerin use in MI and for nausea and vomiting associated with morphine use in MI.^b

Treatment of sudden-onset sinus node suppression complicated by hypotension or ventricular irritability.^b

Treatment of chronic symptomatic sinus node dysfunction when a permanent pacemaker is not implanted.^b

Cautiously in the presence of acute myocardial ischemia or MI because heart rate is a major determinant of myocardial oxygen requirements.^{b 106 108}

Cautiously and with appropriate monitoring following cardiac transplantation; may be ineffective due to lack of vagal innervation in transplanted heart.¹⁰⁶ Risk of paradoxical slowing of the heart rate and high-degree AV block in patients receiving atropine after cardiac transplantation.¹⁰⁶

VF and VT have occurred rarely following IV administration of atropine sulfate.^{b 108}

Diagnostic Uses in Cardiac Disorders

Diagnosis of sinus node dysfunction†.^b

Evaluation of CAD during atrial pacing†.^b

Diagnosis of MI in Wolff-Parkinson-White syndrome†.^b

Pesticide Poisoning

Concomitantly with a cholinesterase reactivator (pralidoxime chloride) to reverse muscarinic effects associated with toxic exposure to organophosphate anticholinesterase pesticides.^{103 105 b}

Reversal of muscarinic effects associated with toxic exposure to carbamate anticholinesterase pesticides.^{105 b l} Concomitant cholinesterase reactivator (pralidoxime chloride) therapy may not be necessary.^{b l}

A challenge (test) dose of atropine may be useful in diagnosing cholinergic poisoning†.^l Failure of the challenge dose to elicit typical antimuscarinic effects (e.g., mydriasis, tachycardia, dry mucous membranes) strongly suggests the presence of organophosphate or carbamate poisoning.^l

Chemical Warfare Agent Poisoning

Concomitantly with a cholinesterase reactivator (pralidoxime chloride) to reverse muscarinic effects associated with toxic exposure to organophosphate anticholinesterase nerve agents (e.g., sarin, soman, tabun, VX [methylphosphonothioic acid]) in the context of chemical warfare or terrorism.^{b 101 102 103 104 105}

Initial management of nerve agent poisoning includes aggressive airway control and ventilation (administration of nebulized β-adrenergic agonist [e.g., albuterol] and antimuscarinics [e.g., ipratropium bromide] may be necessary), and administration of atropine and pralidoxime chloride;^{101 102 103} diazepam may be needed for seizure control.¹⁰¹

Mushroom Poisoning

Treatment of muscarinic effects associated with toxic ingestion of mushrooms containing muscarine^{f l} (e.g., certain members of the Clitocybe and Inocybe genera).^l However, substantial toxicity is uncommon, and supportive symptomatic care (e.g., atropine) rarely is necessary.^l

Although certain members of the Amanita genus also contain muscarine, the amount is limited.^l

Radiographic Uses

Facilitation of hypotonic duodenography^e by reducing motility and spasm; however, glucagon appears to be more effective and generally is preferred.^b

Facilitation of hypotonic contrast examination of the colon^e by reducing motility and spasm; however, glucagon appears to be more effective and generally is preferred in these examinations.^b

Has been used to increase visualization of the urinary tract in excretion urography.^{b e}

Bronchospasm

Has been used by oral inhalation as a quick-relief bronchodilator for the short-term symptomatic treatment of acute symptoms and exacerbations of reversible bronchospasm associated with bronchial asthma, bronchitis, and COPD; however, a solution of the drug for oral inhalation no longer is commercially available in the US.^b Ipratropium bromide currently is the anticholinergic of choice when such therapy is indicated.^{h i}

Has been used in a combined regimen of oral inhalation and IM injection to prevent bronchospasm.^{b c}

GI Disorders

Has been used as an adjunct in the treatment of peptic ulcer disease;^{b c} however, no conclusive data that it aids in the healing, decreases the rate of recurrence, or prevents complications of peptic ulcers.^b

With the advent of more effective therapies for the treatment of peptic ulcer disease, antimuscarinics have only limited usefulness in this condition.^b

Has been used in the treatment of functional disturbances of GI motility such as irritable bowel syndrome;^{b g} however, efficacy is limited.^b Use only if other measures (e.g., diet, sedation, counseling, amelioration of environmental factors) have been of little or no benefit.^b

GU Disorders

Adjunctive therapy in the management of hypermotility disorders of the lower urinary tract.^b May provide symptomatic relief, but the underlying cause should be determined and specifically treated.^b

With the exception of uninhibited or reflex neurogenic bladder, there is generally little evidence to support the use of antimuscarinics in the treatment of various GU disorders.^c

Biliary Disorders

Do not rely on for relief of biliary tract disorders (e.g., combined with opiates for biliary colic) because of weak biliary antispasmodic action.^b

Pancreatitis

Has been used to decrease gastric and pancreatic secretions in acute pancreatitis, but little evidence of benefit.^b

Atropine Dosage and Administration

Administration

Administer by sub-Q, IM, or IV injection.^{105 106 108 b e f g}

For ACLS during CPR, may be administered via an endotracheal tube^{b 106 108 f} or by intraosseous infusion†^{b 106 108} when IV injection is not possible. Although endotracheal administration is possible, IV or intraosseous† drug administration is preferred because of more predictable drug delivery and pharmacologic effect.¹⁰⁶

For bronchodilation, has been administered via oral inhalation, via nebulization, or by injection.^b

IV Injection

CPR: When a vein has not been cannulated prior to the arrest, a peripheral vein is preferred because central venous access requires interruption of chest compressions.^{b 106}

If a central venous catheter is already in place at the time of arrest, it can be used because of more rapid onset (in adults), more secure access to circulation, and avoidance of tissue infiltration.^{b 106 108} Central venous line placement should be avoided in patients who are candidates for pharmacologic reperfusion (e.g., with thrombolytic therapy).^{b 106 108}

Because peak drug concentrations are lower and circulation times are increased with peripheral vein administration compared with central venous injection, inject rapidly IV during resuscitative efforts and follow by a 20-mL flush of IV fluid.^{b 106}

If injected IV in an extremity, elevate the extremity for 10–20 seconds; when injected peripherally, 1–2 minutes generally are required for a drug to reach central circulation.^{b 106}

Rate of Administration

Preferably give IV rapidly because slow injection may cause a paradoxical slowing of the heart rate.^b

IV Infusion

Occasionally, infused IV† for the management of muscarinic poisoning (e.g., organophosphate pesticides).^l

Rate of Administration

Children: Has been infused IV† at a rate of 0.025 mg/kg per hour for muscarinic poisoning.^l

Adults: Has been infused IV† at an initial rate of 0.5–1 mg/hour for muscarinic poisoning, increasing as needed according to response and tolerance.^l

IM Injection

For self-medication, instruct patients and their caregivers carefully in proper administration techniques using the auto-injector provided by the manufacturer.¹⁰⁵

Inject the weight-appropriate dose IM only into the anterolateral aspect of the thigh.¹⁰⁵

In very thin patients and small children, bunch up the thigh prior to injection to provide a thicker injection area.¹⁰⁵

AtroPen 0.5, 1, or 2 mg: Grasp the prefilled auto-injector with the green tip pointed downward; the yellow activation (safety) cap should be removed.¹⁰⁵ Point the green tip toward the outer thigh, swing and jab it firmly into the outer thigh so that the auto-injector is perpendicular (90° angle) to the thigh, and hold firmly in the thigh for at least 10 seconds until the dose is delivered.¹⁰⁵

AtroPen 0.25 mg: Grasp the prefilled auto-injector with the black tip pointed downward; the grey activation (safety) cap should be removed.¹⁰⁵ Point the black tip toward the outer thigh and jab it firmly into the outer thigh so that the auto-injector is perpendicular (90° angle) to the thigh, and hold firmly in the thigh for at least 10 seconds until the dose is delivered.¹⁰⁵

Administer through clothing if necessary.¹⁰⁵

Massage injection area for several seconds.¹⁰⁵

If the needle is not exposed, check that the safety cap was removed and repeat administration but press harder.¹⁰⁵

Do not remove the activation cap until ready to use.¹⁰⁵

The auto-injector cannot be refilled nor can the exposed needle be retracted.¹⁰⁵

After use, bend the needle back against a hard surface and dispose of properly.¹⁰⁵

Endotracheal Administration

When IV or intraosseous† access cannot be established, may administer by the endotracheal route.¹⁰⁶

Dilution

Adults: Dilute dose in 5–10 mL of 0.9% sodium chloride injection or sterile water.¹⁰⁶

Intraosseous Administration

When IV administration is not possible, may be given by intraosseous† administration for CPR.¹⁰⁶

Oral Inhalation

Has been administered via oral inhalation using a nebulizer, but a solution for oral inhalation no longer is commercially available in the US.^b

Dilution

For administration via a nebulizer, the dose as a 0.2 or 0.5% solution has been diluted with 3–5 mL of 0.45 or 0.9% sodium chloride solution.^b

Dosage

Higher than recommended dosage sometimes has been required for therapeutic effect.^b Dosage should be titrated until therapeutic effect is achieved or adverse effects become intolerable (using the lowest possible effective dosage).^b

Pediatric Patients

Usual Dosage

Oral

Usual oral dosage is 0.01 mg/kg^f or 0.3 mg/m², but generally not exceeding 0.4 mg, every 4–6 hours.^b

IV, IM, or Sub-Q

Usual IV, IM, or sub-Q dose is 0.01 mg/kg^f or 0.3 mg/m², but generally not exceeding 0.4 mg^b ; if necessary, this dose may be repeated every 4–6 hours.^{b k}

Surgery

Preoperatively to Decrease Secretions and Block Cardiac Vagal Reflexes

IV, IM, or Sub-Q

Children weighing >20 kg: 0.4 mg given 30–60 minutes before anesthesia.^{PDH b} Higher doses (e.g., 0.5–0.6 mg) occasionally have been used in larger children (e.g., 32–41 kg).^{e j}

Children weighing <20 kg: 0.1 mg for 3 kg, 0.2 mg for 7–9 kg, or 0.3 mg for 12–16 kg given 30–60 minutes before anesthesia.^{PDH b}

Muscarinic Blockade during Anticholinesterase Reversal of Curariform Neuromuscular Blockade

Administer concurrently with (but in a separate syringe) or a few minutes before the anticholinesterase agent.^b

If bradycardia is present, administer before the anticholinesterase agent to increase pulse to about 80 bpm.^b

IV

Neonates and infants: 0.02-mg/kg dose of atropine sulfate concomitantly with each 0.04-mg/kg dose of neostigmine methylsulfate.^b

Children: 0.01- to 0.04-mg/kg dose of atropine sulfate concomitantly with each 0.025- to 0.08-mg/kg dose of neostigmine methylsulfate.^k

CPR and Cardiac Arrhythmias

Bradycardia and Pediatric Advanced Life Support

Current guidelines for ACLS no longer include recommendations for use in neonates.^{b 106} (See CPR and Cardiac Arrhythmias under Uses.)

Bradycardia may respond to adequate oxygenation and ventilation alone.¹⁰⁶

IV or Intraosseous†

Children and adolescents: 0.02 mg/kg, repeat once if needed; minimum pediatric dose is 0.1 mg and maximum single dose is 0.5 mg in children and 1 mg in adolescents.¹⁰⁶

Endotracheal

Children and adolescents: 0.03 mg/kg; repeat once if needed.¹⁰⁶

Follow each dose with a 5-mL flush of 0.9% sodium chloride injection; thereafter, apply 5 manual ventilations to promote absorption.¹⁰⁶

Pesticide Poisoning

Organophosphate Anticholinesterase Pesticides

Preferably should be administered IV, especially the initial dose.^b

A cholinesterase reactivator (pralidoxime) is administered concomitantly.^{b l m}

Some degree of atropinism should be maintained for at least 48 hours; prolonged therapy (e.g., for several weeks) may be necessary in severe cases.^{l m}

IV or IM

Children: 0.05 mg/kg IV (preferable) or IM up to an adult dose, repeated every 2–30 minutes until muscarinic signs and symptoms disappear.^{b l}

Alternatively, infuse IV† at a rate of 0.025 mg/kg per hour; continuous infusions have been maintained for up to several weeks in severe cases.^l

Adolescents: 1–2 mg IV (preferable) or IM, repeated every 2–60 minutes until muscarinic symptoms disappear.^{b e f l}

For severe cases, 2–6 mg may be given initially, repeating doses every 2–60 minutes.^{b e f l}

IM Self-administration

For self-administration using a prefilled auto-injector (e.g., AtroPen), dose is based on body weight and symptom severity.¹⁰⁵

Mild symptoms include miosis, blurred vision, tearing, runny nose, hypersalivation, drooling, wheezing, muscle fasciculations, nausea/vomiting.¹⁰⁵

Severe symptoms include behavioral changes, severe breathing difficulty, severe respiratory secretions, severe muscle twitching, involuntary defecation or urination, seizures, unconsciousness.¹⁰⁵

Children <7 kg: Inject 0.25 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 0.25-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children <7 kg who present with severe symptoms or are unconscious: Inject three 0.25-mg IM doses in rapid succession.¹⁰⁵

Children <7 kg: Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Children 7–18 kg: Inject 0.5 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 0.5-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children 7–18 kg who present with severe symptoms or are unconscious: Inject three 0.5-mg IM doses in rapid succession.¹⁰⁵

Children 7–18 kg: Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Children 18–41 kg: Inject 1 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 1-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children 18–41 kg who present with severe symptoms or are unconscious: Inject three 1-mg IM doses in rapid succession.¹⁰⁵

Children 18–41 kg: Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Children >41 kg: Inject 2 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 2-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children >41 kg who present with severe symptoms or are unconscious: Inject three 2-mg IM doses in rapid succession.¹⁰⁵

Children >41 kg: Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Carbamate Anticholinesterase Pesticides

Carbamate poisoning is treated with the same doses of atropine sulfate as for organophosphate poisoning and IM self-administration can be employed when necessary.^{105 l} (See Organophosphate Anticholinesterase Pesticides under Dosage.)

Concomitant cholinesterase reactivator (pralidoxime chloride) therapy may not be necessary and atropine therapy generally is less prolonged (e.g., only 1 or 2 days) and symptoms usually do not recur once asymptomatic.^l

Chemical Warfare Agent Poisoning

Organophosphate Anticholinesterase Nerve Agents

Administer IM in out-of-hospital setting or emergency department.^{101 105 b}

A cholinesterase reactivator (pralidoxime chloride) is administered concomitantly.^{b l m}

Give diazepam for seizure control.¹⁰¹

Total atropine sulfate doses usually are much less than those required for organophosphate anticholinesterase pesticide poisoning.^l

IM

Minimum dose in children is 0.1 mg.^l

Children 0–2 years of age with mild to moderate symptoms: Usual initial IM dose is 0.05 mg/kg.^{101 b}

Children 0–2 years of age with severe symptoms: Usual initial IM dose is 0.1 mg/kg.^{101 b}

Children 2–10 years of age with mild to moderate symptoms: Usual initial IM dose is 1 mg.^{101 b}

Children 2–10 years of age with severe symptoms: Usual initial IM dose is 2 mg.^{101 b}

Children older than 10 years of age with mild to moderate symptoms: Usual initial IM dose is 2 mg.^{101 b}

Children older than 10 years of age with severe symptoms: Usual initial IM dose is 4 mg.^{101 b}

Repeat doses every 2–10 minutes as needed until muscarinic toxicity resolves (e.g., secretions have diminished and breathing is comfortable or airway resistance has returned to near normal).^{101 b l}

IM Self-administration

For self-administration using a prefilled auto-injector (e.g., AtroPen), dose is based on body weight and symptom severity.¹⁰⁵

Mild symptoms include miosis, blurred vision, tearing, runny nose, hypersalivation, drooling, wheezing, muscle fasciculations, nausea/vomiting.¹⁰⁵

Severe symptoms include behavioral changes, severe breathing difficulty, severe respiratory secretions, severe muscle twitching, involuntary defecation or urination, seizures, unconsciousness.¹⁰⁵

Children <7 kg: Inject 0.25 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 0.25-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children <7 kg who present with severe symptoms or are unconscious: Inject three 0.25-mg IM doses in rapid succession.¹⁰⁵

Children <7 kg: Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Children 7–18 kg: Inject 0.5 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 0.5-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children 7–18 kg who present with severe symptoms or are unconscious: Inject three 0.5-mg IM doses in rapid succession.¹⁰⁵

Children 7–18 kg: Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Children 18–41 kg: Inject 1 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 1-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children 18–41 kg who present with severe symptoms or are unconscious: Inject three 1-mg IM doses in rapid succession.¹⁰⁵

Children 18–41 kg: Additional doses (i.e., >3) may be given every 5–10 minutes^l but only under the supervision of trained medical personnel.¹⁰⁵

Children >41 kg: Inject 2 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 2-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Children >41 kg who present with severe symptoms or are unconscious: Inject three 2-mg IM doses in rapid succession.¹⁰⁵

Children >41 kg: Additional doses (i.e., >3) may be given every 5–10 minutes^l but only under the supervision of trained medical personnel.¹⁰⁵

IV

Children 0–2 years of age with mild, moderate, or severe symptoms: May receive 0.02 mg/kg IV, if treated in an emergency department.^{101 b}

Mushroom Poisoning

Muscarine-containing Clitocybes and Inocybes

IV

If needed for severe symptoms, 0.02 mg/kg IV (minimum of 0.1 mg), repeated and titrated as needed according to response.^l

Bronchospasm

Treatment of Acute Exacerbations of Asthma

Oral Inhalation

Children: 0.05 mg/kg 3 or 4 times daily via nebulization;^b individual dose may be based on the patient’s weight as suggested in the following table, and may be adjusted according to the patient’s response and tolerance.^b

Weight	Pediatric Dose
15–25.8 kg	1 mg
25.9–37.6 kg	1.5 mg
37.7–63.2 kg	2.5 mg

Adults

Usual Dosage

Oral

Usual oral dosage is 0.4–0.6 mg (range: 0.1–1.2 mg) every 4–6 hours.^b

IV, IM, or Sub-Q

Usual IV, IM, or sub-Q dose is 0.4–0.6 mg (range: 0.3–1.2 mg); if necessary, this dose may be repeated every 4–6 hours.^b

Surgery

Preoperatively to Decrease Secretions and Block Cardiac Vagal Reflexes

IV, IM, or Sub-Q

0.4 mg (range: 0.2–1 mg) given 30–60 minutes before anesthesia.^{b e f}

Muscarinic Blockade during Anticholinesterase Reversal of Curariform Neuromuscular Blockade

IV

0.6–1.2 mg for each 0.5–2.5 mg of neostigmine methylsulfate or 10–20 mg of pyridostigmine bromide given.^b

Administer concurrently with (but in a separate syringe) or a few minutes before the anticholinesterase agent.

If bradycardia is present, administer before the anticholinesterase agent to increase pulse to 80 bpm.^b

CPR and Cardiac Arrhythmias

Selection of dosing interval (3–5 minutes) requires the clinician’s judgment about the severity of the patient’s symptoms; the shorter dosing intervals should be used in the more distressed patients (e.g., those with ventricular asystole).^{108 b f}

Endotracheal

Can administer via an endotracheal tube when atropine cannot be administered IV for bradycardia or ACLS during CPR.^{b 106 j}

Optimum dose for bradycardia and ACLS not established.¹⁰⁶ Doses 2–2.5 times usual IV doses have been recommended.^{b 106}

One manufacturer recommends a dose of 1–2 mg.^f

Intraosseous†

Can administer by intraosseous† infusion when atropine cannot be administered IV for ACLS during CPR.^{b 106}

Intraosseous doses usually have been the same as those administered IV, although some evidence suggests that intraosseous doses should be higher than those administered IV.^b

Asystole

IV

Usually, 1 mg; the dose may be repeated in 3–5 minutes if asystole persists up to a total of 3 doses (or up to 3 mg).¹⁰⁶

Slow Pulseless Electrical Activity

IV

Usually, 1 mg; the dose may be repeated in 3–5 minutes if necessary up to a total of 3 doses (or up to 3 mg).¹⁰⁶

Bradycardia

IV

0.5 mg; may repeat dose at 3- to 5-minute intervals up to a total dose of 3 mg.¹⁰⁶

Pesticide Poisoning

Organophosphate Anticholinesterase Pesticides

Preferably should be administered IV, especially the initial dose.^b

A cholinesterase reactivator (pralidoxime chloride) is administered concomitantly.^{b l m}

Some degree of atropinism should be maintained for at least 48 hours; prolonged therapy (e.g., for several weeks) may be necessary in severe cases.^{l m}

IV or IM

1–2 mg IV (preferable) or IM, repeated every 2–60 minutes until muscarinic symptoms disappear.^{b e f l} For severe cases, 2–6 mg may be given initially, repeating doses every 2–60 minutes.^{b e f l}

Alternatively, infuse IV at an initial rate of 0.5–1 mg/hour, adjusting rate according to response.^l

Mildly symptomatic poisoning may respond to 1–2 mg for reversal of muscarinic toxicity whereas moderate poisoning commonly requires total doses up to 40 mg.^l

For severe poisoning, 5-mg doses may be repeated every 2–3 minutes for stabilization.^l

Cumulative doses up to 1 g in 24 hours or 11 g over a course of treatment have been used.^l

IM Self-administration

For self-administration using a prefilled auto-injector (e.g., AtroPen), dose is based on body weight and symptom severity.¹⁰⁵

Mild symptoms include miosis, blurred vision, tearing, runny nose, hypersalivation, drooling, wheezing, muscle fasciculations, nausea/vomiting.¹⁰⁵

Severe symptoms include behavioral changes, severe breathing difficulty, severe respiratory secretions, severe muscle twitching, involuntary defecation or urination, seizures, unconsciousness.¹⁰⁵

Adults >41 kg: Inject 2 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 2-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Adults >41 kg who present with severe symptoms or are unconscious: Inject three 2-mg IM doses in rapid succession.¹⁰⁵

Additional doses (i.e., >3) should only be administered under the supervision of trained medical personnel.¹⁰⁵

Adults <41 kg: Pediatric doses can be used.¹⁰⁵ (See Pediatric Patients: Pesticide Poisoning, under Dosage.)

Oral

Oral therapy can replace parenteral therapy for maintenance as needed.^b

0.5–1 mg may be administered orally at intervals of several hours as maintenance therapy until signs and symptoms completely subside.^b

Carbamate Anticholinesterase Pesticides

Carbamate poisoning is treated with the same doses of atropine sulfate as for organophosphate poisoning and IM self-administration can be employed when necessary.^{105 l} (See Organophosphate Anticholinesterase Pesticides under Dosage.)

Concomitant cholinesterase reactivator (pralidoxime chloride) therapy may not be necessary and atropine therapy generally is less prolonged (e.g., only 1 or 2 days) and symptoms usually do not recur once asymptomatic.^l

Chemical Warfare Agent Poisoning

Organophosphate Anticholinesterase Nerve Agents

Administered IM in out-of-hospital setting or emergency department.^{101 105 b}

A cholinesterase reactivator (pralidoxime chloride) is administered concomitantly.^{b l m}

Give diazepam for seizure control.¹⁰¹

Total atropine sulfate doses usually are much less than those required for organophosphate anticholinesterase pesticide poisoning.^l

IM or IV

Mild to moderate symptoms: Usual initial IM dose is 2–4 mg.^{101 b l}

Severe symptoms: 5–6 mg.^{101 b l}

Frail geriatric patients with mild to moderate symptoms: 1 mg.^{101 b}

Frail geriatric patients with severe symptoms: 2–4 mg.^{101 b}

Repeat doses every 2–10 minutes as needed until muscarinic toxicity resolves (e.g., secretions have diminished and breathing is comfortable or airway resistance has returned to near normal).^{101 b l}

Up to 15–20 mg may be required within the first 3 hours,¹⁰⁴ but most patients respond to <20 mg usually during the initial 24 hours.^l In a report of sarin poisoning, <20% of moderately symptomatic patients required more than 2 mg.^l Pralidoxime chloride is administered concomitantly with atropine.¹⁰¹

IM Self-administration

For self-administration using a prefilled auto-injector (e.g., AtroPen), dose is based on body weight and symptom severity.¹⁰⁵

Mild symptoms include miosis, blurred vision, tearing, runny nose, hypersalivation, drooling, wheezing, muscle fasciculations, nausea/vomiting.¹⁰⁵

Severe symptoms include behavioral changes, severe breathing difficulty, severe respiratory secretions, severe muscle twitching, involuntary defecation or urination, seizures, unconsciousness.¹⁰⁵

Adults >41 kg: Inject 2 mg IM initially for mild symptoms.¹⁰⁵ If severe symptoms develop, inject 2 additional 2-mg IM doses in rapid succession 10 minutes after the initial dose.¹⁰⁵

Adults >41 kg who present with severe symptoms or are unconscious: Inject three 2-mg IM doses in rapid succession.¹⁰⁵

Additional doses (i.e., >3) may be given every 5–10 minutes^l but only under the supervision of trained medical personnel.¹⁰⁵

Adults <41 kg: Pediatric doses can be used.¹⁰⁵ (See Pediatric Patients: Pesticide Poisoning, under Dosage.)

Mushroom Poisoning

Muscarine-containing Clitocybes and Inocybes

IV

If needed for severe symptoms, 1–2 mg IV (minimum of 0.1 mg), repeated and titrated as needed according to response.^l

Radiographic Uses

Hypotonic Radiograph of the GI Tract

IM

1 mg IM.^{b e}

Bronchospasm

Treatment of Acute Exacerbations of Asthma

Oral Inhalation

0.025 mg/kg (usually up to 2.5 mg) 3 or 4 times daily via nebulization;^b individual dose may be based on the patient’s weight as suggested in the following table, and may be adjusted according to the patient’s response and tolerance.^b

Adult Weight	Adult Dose
30.5–50.8 kg	1 mg
50.9–75.8 kg	1.5 mg
75.9–126.4 kg	2.5 mg

Prescribing Limits

Pediatric Patients

CPR and Cardiac Arrhythmias

Bradycardia and Pediatric Advanced Life Support

IV or Intraosseous†

Children: Maximum single dose is 0.5 mg; maximum total dose is 1 mg.^{b 106}

Adolescents: Maximum single dose is 1 mg; maximum total dose is 2 mg.^{b 106}

Other Uses

Oral

Generally, not exceeding 0.4 mg.^b

IV

Generally, not exceeding 0.4 mg.^b

IM

Generally, not exceeding 0.4 mg.^b

Adults

CPR and Cardiac Arrhythmias

Asystole, Slow Pulseless Electrical Activity, and Bradycardia

IV

Total dose usually should not exceed 3 mg (0.04 mg/kg) in asystole, slow pulseless electrical activity, or bradycardia because complete vagal blockade (total vagolytic dose) generally occurs.^{b f 106}

Pesticide Poisoning

Organophosphate Anticholinesterase Pesticides

Maximum up to 1 g in 24 hours (with a cholinesterase activator [pralidoxime chloride]), depending on muscarinic severity.^l

Total cumulative doses up to 11 g (with a cholinesterase activator [pralidoxime chloride]) during a course of treatment, depending on muscarinic severity.^l

Chemical Warfare Agent Poisoning

Organophosphate Anticholinesterase Nerve Agents

IM or IV

Total atropine sulfate doses usually are much less than those required for organophosphate anticholinesterase pesticide poisoning.^l

Up to 15–20 mg may be required within the first 3 hours,¹⁰⁴ but most patients respond to <20 mg during the initial 24 hours.^l

Bronchospasm

Treatment of Acute Exacerbations of Asthma

Oral Inhalation

Usually, up to 2.5 mg per dose via nebulization;^b minimally increased efficacy but increased adverse effects with higher doses.^b

Special Populations

Hepatic Impairment

No specific hepatic dosage recommendations.^{105 e g}

Renal Impairment

No specific renal dosage recommendations.^{105 e g}

Geriatric Patients

Similar response between geriatric and younger patients.^f In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.^{101 f}

Cautions for Atropine

Contraindications

• No absolute contraindications to use in life-threatening conditions (e.g., poisoning by organophosphate nerve agents and pesticides).¹⁰⁵

• Relative contraindications include:

  • known hypersensitivity to atropine or any ingredient in the formulation^{105 b}

  • angle-closure glaucoma^{105 b c e f g}

  • obstructive uropathy (e.g., bladder neck obstruction secondary to prostatic hypertrophy)^c

  • obstructive GI disease (e.g., pyloroduodenal stenosis, achalasia)^c

  • paralytic ileus^c

  • intestinal atony (especially in geriatric and debilitated patients)^c

  • severe ulcerative colitis^c

  • toxic megacolon^c

  • tachycardia secondary to cardiac insufficiency or thyrotoxicosis

  • acute hemorrhage when cardiovascular status is unstable^c

  • myasthenia gravis (unless used to reduce adverse muscarinic effects of an anticholinesterase agent such as neostigmine)^c

Warnings/Precautions

Warnings

Overdosage

Avoid overdosage, especially with IV administration.^f

Pediatric patients are particularly susceptible to overdosage.^f

Pesticide and Chemical Warfare Agent Poisoning

Use in patients with a history of anaphylactic reaction to atropine and mildly symptomatic organophosphate pesticide or nerve agent poisoning only when there is adequate medical supervision.¹⁰⁵

Severe breathing difficulty requires artificial respiration because atropine alone is not dependable in reversing respiratory muscle weakness or paralysis.¹⁰⁵

Administer with extreme caution when the symptoms of nerve agent poisoning are less severe in patients with disorders of heart rhythm (e.g., atrial flutter), substantial renal insufficiency, or a recent MI.¹⁰⁵

No more than 3 doses should be self-administered IM; additional doses require medical supervision.¹⁰⁵

Sensitivity Reactions

Parabens present in multiple-dose preparations may cause hypersensitivity reactions.^c

Anaphylaxis, urticaria, rash (e.g., scarlatiniform) that may progress to exfoliation, delayed hypersensitivity reactions, and various dermal manifestations.^{c 105 e}

Major Toxicities

Cardiovascular Effects

Caution in tachyarrhythmias, CHF, or CAD because antimuscarinics block vagal inhibition of the SA nodal pacemaker.^c

CNS Disturbances

Large or toxic doses or usual doses in patients with excess susceptibility may produce marked CNS disturbances (e.g., ranging from marked excitement, ataxia, hallucination, depression, and/or disorientation to active delirium to coma to death [secondary to respiratory failure]).^{105 f g}

Marked somnolence in susceptible patients.^c

Mental confusion and/or excitement, especially in geriatric patients.^c

GI Disturbances

Extreme caution in known or suspected GI infections because of decreased GI motility and retention of causative organism and/or toxins.^c

Extreme caution in mild to moderate ulcerative colitis because of suppressed intestinal motility and resultant paralytic ileus and toxic megacolon.^c

Extreme caution in diarrhea (especially in patients with ileostomy or colostomy) because it may be an early sign of intestinal obstruction.^c

Caution in gastric ulcer because of delayed gastric emptying and possible antral stasis.^c

Caution in esophageal reflux and hiatal hernia because of decreased gastric motility and lower esophageal sphincter pressure leading to gastric retention and reflux aggravation.^c

GU Disturbances

Extreme caution in patients with partial obstructive uropathy because of decreased tone and amplitude of contractions of ureters and bladder and resultant urinary retention.^c (See Contraindications under Cautions)

Respiratory Effects

Caution with systemically administered atropine in debilitated patients with chronic pulmonary disease because a reduction in bronchial secretions may lead to inspissation and formation of bronchial plugs; however, has been used effectively as bronchodilator when administered via oral inhalation.

Thermoregulatory Effects

Exposure to high environmental temperatures may result in heat prostration due to decreased sweating.^c Increased risk of hyperthermia in patients who are febrile.^c

General Precautions

Neuropathy

Extreme caution in patients with autonomic neuropathy.^c

Down’s Syndrome, Spastic Paralysis, and Brain Damage

Increased sensitivity to antimuscarinic effects (e.g., mydriasis, positive chronotropic effect).^c

Hypertension

Caution in hypertensive patients.^c

Hyperthyroidism

Caution in hyperthyroid patients.^c

Seizure Management in Anticholinesterase Poisoning

Use barbiturates cautiously to manage seizures because the drugs are potentiated by anticholinesterases.¹⁰⁵ Diazepam is preferred for seizure control.¹⁰¹

Specific Populations

Pregnancy

Category C.^{105 c f g}

Lactation

Atropine is found in human milk in trace amounts; use caution when administered to a nursing woman.¹⁰⁵

Pediatric Use

Safety and efficacy in the setting of organophosphate pesticide poisoning established in children of all ages.¹⁰⁵

Increased susceptibility to the effects of atropine.^{105 c f} More susceptible than adults to toxic effects; deaths at doses as low as 10 mg.^c

May produce fever through inhibition of heat loss by evaporation.^{e g}

Infants, patients with Down’s syndrome (mongolism), and children with spastic paralysis or brain damage may be hypersensitive to antimuscarinic effects (e.g., mydriasis, positive chronotropic effect).^c

Geriatric Use

Increased susceptibility to the effects of atropine.^{105 c} Mental confusion and/or excitement are especially likely in geriatric patients.^c

Use with caution in all patients >40 years of age.^f

Monitor closely for urine retention^{PDH e} in elderly men with BPH.^{c PDH}

Constipation and difficulty in micturition in elderly patients.^f

Hepatic Impairment

Use with caution in hepatic disease.^c

Renal Impairment

Use with caution in renal disease.^c

Common Adverse Effects

Most adverse effects are manifestations of pharmacologic effects at muscarinic-cholinergic receptors and usually are reversible when therapy is discontinued.^c

Severity and frequency of adverse effects are dose related and individual intolerance varies greatly; adverse effects occasionally may be obviated by a reduction in dosage but this also may eliminate potential therapeutic effects.^{c e}

Frequent effects include xerostomia (dry mouth), dry skin, blurred vision, cycloplegia, mydriasis, photophobia, anhidrosis, urinary hesitancy and retention, tachycardia, palpitation, xerophthalmia, and constipation,^{105 c e f g} which may appear at therapeutic or subtherapeutic doses.^c Xerostomia is the dose-limiting effect.^c

Other common effects include increased ocular tension (especially in patients with angle-closure glaucoma), loss of taste, headache, nervousness, restlessness, drowsiness, weakness, dizziness, flushing, insomnia, nausea, vomiting, bloated feeling, anhidrosis (especially in hot environments),^{105 e f} fever,^e mild to moderate pain at the injection site,^{105 c} loss of libido, and erectile dysfunction (via block of cholinergically mediated vasodilation).^{105 c}

Interactions for Atropine

Drugs with Anticholinergic Effects

Additive adverse effects resulting from cholinergic blockade (e.g., xerostomia, blurred vision, constipation).^c Advise of possibility of increased anticholinergic effects and monitor carefully.^c

Effects on GI Absorption of Drugs

By inhibiting the motility of the GI tract and prolonging GI transit time, antimuscarinics have the potential to alter GI absorption of various drugs.^c

Specific Drugs

Drug	Interaction	Comments
Amantadine	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Antacids	Decreased GI absorption of atropinec	Administer oral atropine at least 1 hour before antacidsc
Anticholinergic drugs	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Antihistamines (anticholinergic)	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Antiparkinsonian (antimuscarinic) agents	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Corticosteroids	Increased IOPc	Caution; monitor IOPc
Digoxin (slow dissolving)	Increased serum digoxinc	Use digoxin oral solution (elixir) or rapidly dissolving tablets (e.g., Lanoxin)c
Disopyramide	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Ketoconazole	Increased gastric pH decreases ketoconazole absorptionc	Administer atropine at least 2 hours after ketoconazolec
Levodopa	Increased GI metabolism of levodopa & decreased systemic concentrationsc	Adjust levodopa dosage if atropine is started or discontinuedc
Meperidine	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Mexiletine	Decreased GI absorption rate of mexiletine; no effect on bioavailabilityf
Muscle (anticholinergic) relaxants	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Phenothiazines	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Potassium chloride	Slowed GI transit potentiates adverse GI effects of oral potassium chloride (especially wax-matrix tablets)c	Caution if used concomitantly; monitor for possible GI mucosal lesionsc
Procainamide	Increased anticholinergic effectsc	Inform patient and monitor carefullyc
Pralidoxime	Increased rate of atropinizationc
Tricyclic antidepressants	Increased anticholinergic effectsc	Inform patient and monitor carefullyc

Atropine Pharmacokinetics

Absorption

Bioavailability

Well absorbed (90%) from the GI tract, principally from upper small intestine.^b

Rapidly and well absorbed after IM injection.^b Physical exercise, either prior to or immediately following IM injection, increases absorption due to muscle perfusion and decreases clearance.^f

Well absorbed following endotracheal administration.^{c 106 108} Water dilution increases endotracheal absorption^{106 108} but adversely affects arterial oxygen pressure (PaO₂) relative to sodium chloride dilution.¹⁰⁸

Well absorbed following oral inhalation,^b but only small amounts reach systemic circulation.^c

Onset

Inhibition of salivation occurs within 30 minutes or 30–60 minutes and peaks within 1–1.6 or 2 hours after IM or oral administration, respectively.^b

Increase in heart rate occurs within 2–4 minutes after IV injection.^b

Increase in heart rate occurs within 5–40 minutes or 0.5–2 hours and peaks within 20–60 minutes or 1–2 hours after IM or oral administration, respectively.^b

Ocular effects are delayed following systemic administration.^b

Bronchodilation (as determined by forced expiratory volume in 1 second [FEV₁]) occurs within 15 minutes and is maximal within 0.25–1.5 hours after oral inhalation.^b

Duration

Inhibition of salivation persists for up to 4 hours.^b

Plasma Concentrations

Peak plasma concentrations are reached within 1 hour following oral administration.^b

Following IM administration, peak plasma concentrations are reached within 30 minutes.^b

Following oral inhalation, appears in serum within 15 minutes and peaks within 1.5–4 hours.^b

Distribution

Extent

Rapidly and well distributed throughout the body, including the CNS.^{105 b c}

Traces are found in various secretions, including milk.^f

Crosses the placental barrier and enters fetal circulation^{b f} but is not found in amniotic fluid.^f

Plasma Protein Binding

Binds poorly (about 44%); mainly to α₁-acid glycoprotein.^f

Elimination

Metabolism

Via the liver to several metabolites including tropic acid, atropine (or a chromatographically similar compound), and, possibly, esters of tropic acid and glucuronide conjugates.^b

Elimination Route

About 30–50% of a dose is excreted in urine unchanged.^b

Excreted mainly through the kidneys;^{b PDH} however, small amounts may be excreted in the feces and expired air.^b

Half-life

2–3 hours.^b

Biphasic following IM injection; 2–3-hours initially followed by a terminal half-life of 12.5 hours or longer.^{b PDH}

Special Populations

Elimination half-life is more than doubled in children <2 years and the elderly (>65 years of age) compared with other age groups.^f

No gender effect on pharmacokinetics and pharmacodynamics.^f

Stability

Storage

Effloresces on exposure to dry air and is slowly affected by light.^b

Oral

Tablets

Well-closed containers.^b

Parenteral

Injection

25°C (may be exposed to 15–30°C).^{105 e f}

Protect from freezing and light.^{105 b}

Compatibility

For information on systemic interactions resulting from concomitant use, see Interactions.

Parenteral

Solution Compatibility^HID

Compatible
Sodium chloride 0.9%

Drug Compatibility

Admixture CompatibilityHID

Compatible
Dobutamine HCl
Furosemide
Meropenem
Sodium bicarbonate
Verapamil HCl
Incompatible
Floxacillin sodium

Y-Site CompatibilityHID

Compatible
Abciximab
Amiodarone HCl
Argatroban
Etomidate
Famotidine
Fenoldopam mesylate
Fentanyl citrate
Heparin sodium
Hydrocortisone sodium succinate
Hydromorphone HCl
Inamrinone lactate
Meropenem
Methadone HCl
Morphine sulfate
Nafcillin sodium
Potassium chloride
Sufentanil citrate
Tirofiban HCl
Vitamin B complex with C
Incompatible
Thiopental sodium
Variable
Propofol

Compatibility in SyringeHID

Compatible
Butorphanol tartrate
Chlorpromazine HCl
Cimetidine HCl
Dimenhydrinate
Diphenhydramine HCl
Droperidol
Fentanyl citrate
Glycopyrrolate
Heparin sodium
Hydromorphone HCl
Hydroxyzine HCl
Hydroxyzine HCl with meperidine HCl
Meperidine HCl
Meperidine HCl with hydroxyzine HCl
Meperidine HCl with promethazine HCl
Metoclopramide HCl
Midazolam HCl
Milrinone lactate
Morphine HCl
Morphine sulfate
Nalbuphine HCl
Ondansetron HCl
Papaveretum
Pentazocine lactate
Perphenazine
Prochlorperazine edisylate
Promethazine HCl
Promethazine HCl with meperidine HCl
Ranitidine HCl
Scopolamine HBr
Sufentanil citrate
Incompatible
Cimetidine HCl with pentobarbital sodium
Pentobarbital sodium with cimetidine HCl
Variable
Pentobarbital sodium

Actions

• Competitively inhibits acetylcholine or other cholinergic stimuli at autonomic effectors innervated by postganglionic cholinergic nerves and, to a lesser extent, on smooth muscles that lack cholinergic innervation.^c At usual doses, principally antagonizes cholinergic stimuli at muscarinic receptors and has little or no effect on cholinergic stimuli at nicotinic receptors.^c

• Antimuscarinics also have been referred to as anticholinergics (cholinergic blocking agents), but this term is appropriate only when it describes the antagonism of cholinergic stimuli at any cholinergic receptor, whether muscarinic or nicotinic.^c

• Also have been referred to as parasympatholytics because the antagonized functions principally are under the parasympathetic division of the nervous system.^c

• Receptors at various sites are not equally sensitive to inhibition of muscarinic effects.^c Relative sensitivity of physiologic functions (proceeding from the most sensitive) is as follows: secretions of the salivary, bronchial, and sweat glands; pupillary dilation, ocular accommodation, and heart rate; contraction of the detrusor muscle of the bladder and smooth muscle of the GI tract; and gastric secretion and motility.^c Doses used to decrease gastric secretions are likely to cause dryness of the mouth (xerostomia) and interfere with visual accommodation, and possibly cause difficulty in urinating.^c

• Various antisecretory effects in the GI tract, including reduction of salivation (producing xerostomia) and gastric secretions (only partial reduction in gastric acid secretion).^c Prolonged inhibitory effects on the motility of the esophagus, stomach, duodenum, jejunum, ileum, and colon.^c

• Relaxes lower esophageal sphincter with a resultant decrease in lower esophageal sphincter pressure.^c

• Decreases the tone and amplitude of contractions of the ureters and bladder.^c May cause urinary retention (e.g., in patients with urinary obstruction).^c In patients with uninhibited or reflex neurogenic bladder, the amplitude and frequency of uninhibited contractions are reduced and bladder capacity is increased.^c

• Positive chronotropic effect (increased SA node automaticity), accelerating sinus rate by direct parasympathetic blockade.^c Stimulates the AV functional pacemaker.^c Facilitates AV nodal conduction in a normal AV node.^c

• Can reverse reflex vagal cardiac slowing or asystole such as that induced by inhalation of irritant vapors or by vagal stimulation (e.g., carotid sinus stimulation, pressure on the eyeball).^c

• May cause cutaneous vasodilation, especially at toxic doses (atropine flush).^c

• Reduces secretions from the nose, mouth, pharynx, and bronchi.^c Relaxes smooth muscles of the bronchi and bronchioles with a resultant decrease in airway resistance.^c Potent bronchodilation, particularly in large bronchial airways; especially effective in reversing bronchoconstriction induced by parasympathetic stimulation.^c

• Stimulates the medulla and higher cerebral centers and exhibits CNS effects similar to those produced by antimuscarinics used in the treatment of parkinsonian syndrome (e.g., trihexyphenidyl).^c

• Blocks the responses of the sphincter muscle of the iris and the ciliary muscle of the lens to cholinergic stimulation, producing mydriasis and cycloplegia and a resultant decrease in ocular accommodation.^c Little effect on IOP except with angle-closure glaucoma where IOP may increase.^c

• Reduces the volume of perspiration by inhibiting sweat-gland secretions.^c May suppress sweating sufficiently to increase body temperature.^c

Advice to Patients

• Seek immediate medical attention after injection with an atropine injection auto-injector.¹⁰⁵

• Advise to report serious adverse reactions promptly.^PDH

• Advise that dry mouth may occur.^{105 b e f g}

• Advise of risk of hyperthermia and heat prostration; avoid exposure to high environmental temperatures and avoid use when febrile.^c

• Advise patients receiving chronic therapy of possible blurred vision with the drug; activities that require good, clear vision should be avoided.^{105 b e f g}

• Risk of dizziness or drowsiness; avoid driving or operating machinery until effects on individual are known.^c

• For IM self-administration in nerve gas and pesticide poisoning, proper techniques for storage, attention to expiration dating (replacing before expiration), use, and disposal of the prefilled auto-injector (e.g., AtroPen) and for administration of the drug.¹⁰⁵

• For IM self-administration in nerve gas and pesticide poisoning, importance of understanding the indications for use and the symptoms of poisoning.¹⁰⁵

• For IM self-administration in nerve gas and pesticide poisoning, importance of ensuring adequate understanding of the recognition and treatment of such poisoning and when concomitant cholinesterase reactivator (pralidoxime chloride) therapy may be necessary.¹⁰⁵

• For IM self-administration in nerve gas and pesticide poisoning, importance of not exceeding 3 doses unless under medical supervision.¹⁰⁵

• For IM self-administration in nerve gas and pesticide poisoning, importance of seeking immediate medical attention once the initial dose(s) is administered because respiratory and other supportive care and prolonged atropinization may be needed.¹⁰⁵

• For IM self-administration in nerve gas and pesticide poisoning, importance of recognizing that inadvertent administration when such poisoning is not present could result in atropine toxicity and temporary incapacitation (inability to walk properly, see clearly, or think clearly for several hours or longer).¹⁰⁵

• For self-administration in nerve gas and pesticide poisoning, importance of not contaminating other individuals (e.g., medical and emergency personnel) by clothing exposure; aggressive and safe decontamination by trained personnel is strongly suggested.¹⁰⁵

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.^{105 b}

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.¹⁰⁵

• Importance of informing patients of other important precautionary information.^{105 b} (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Atropine

Routes	Dosage Forms	Strengths	Brand Names	Manufacturer
Bulk	Powder
Parenteral	Injection	equivalent to Atropine Sulfate 0.5 mg/0.7 mL	AtroPen Auto-Injector (“green label”)	Meridian
		equivalent to Atropine Sulfate 1 mg/0.7 mL	AtroPenAuto-Injector (“dark red label”)	Meridian
		equivalent to Atropine Sulfate 2 mg/0.7 mL	AtroPenAuto-Injector (“blue label”)	Meridian

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Atropine Sulfate

Routes	Dosage Forms	Strengths	Brand Names	Manufacturer
Bulk	Powder*
Oral	Tablets	0.4 mg	Sal-Tropine	Hope
Parenteral	Injection	0.05 mg/mL*	Atropine Sulfate Injection
		0.1 mg/mL*	Atropine Sulfate Injection
		0.4 mg/mL*
		0.5 mg/mL*	Atropine Sulfate Injection
		1 mg/mL*

Comparative Pricing

This pricing information is subject to change at the sole discretion of DS Pharmacy. This pricing information was updated 02/2013. Actual costs to patients will vary depending on the use of specific retail or mail-order locations and health insurance copays.

Diphenoxylate-Atropine 2.5-0.025MG/5ML Liquid (ROXANE): 60/$20.60 or 180/$56.65

Diphenoxylate-Atropine 2.5-0.025MG Tablets (MYLAN): 30/$15.99 or 90/$45.97

Lomotil 2.5-0.025MG/5ML Liquid (PFIZER U.S.): 60/$35.99 or 180/$89.97

Lomotil 2.5-0.025MG Tablets (PFIZER U.S.): 30/$45.99 or 90/$115.97