Atropine and Pralidoxime Chloride Injection

Name: Atropine and Pralidoxime Chloride Injection

Side effects

Muscle tightness and sometimes pain may occur at the injection site.


The 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, tachycardia, palpitations, flushing, urinary hesitancy or retention, constipation, abdominal pain, abdominal distention, nausea and vomiting, loss of libido, and impotence. Anhidrosis may produce heat intolerance and impairment of temperature regulation in a hot environment. Dysphagia,

paralytic ileus, and acute angle closure glaucoma, maculopapular rash, petechial rash, and scarletiniform rash have also been reported.

Larger or toxic doses may produce such central effects as restlessness, tremor, fatigue, locomotor difficulties, delirium followed by hallucinations, depression, and, ultimately medullary paralysis and death. Large doses can also lead to circulatory collapse. In such cases, blood pressure declines and death due to respiratory failure may ensue following paralysis and coma.

Cardiovascular adverse events reported in the literature for atropine include, but are not limited to, sinus tachycardia, palpitations, premature ventricular contractions, atrial flutter, atrial fibrillation, ventricular flutter, ventricular fibrillation, cardiac syncope, asystole, and myocardial infarction. (See PRECAUTIONS)

Hypersensitivity reactions will occasionally occur, are usually seen as skin rashes, and may progress to exfoliation. Anaphylactic reaction and laryngospasm are rare.

Pralidoxime Chloride

Pralidoxime can cause blurred vision, diplopia and impaired accommodation, dizziness, headache, drowsiness, nausea, tachycardia, increased systolic and diastolic blood pressure, muscular weakness, dry mouth, emesis, rash, dry skin, hyperventilation, decreased renal function, and decreased sweating when given parenterally to normal volunteers who have not been exposed to anticholinesterase poisons.

In several cases of organophosphorous poisoning, excitement and manic behavior have occurred immediately following recovery of consciousness, in either the presence or absence of pralidoxime administration. However, similar behavior has not been reported in subjects given pralidoxime in the absence of organophosphorous poisoning.

Elevations in SGOT and/or SGPT enzyme levels were observed in 1 of 6 normal volunteers given 1200 mg of pralidoxime intramuscularly, and in 4 of 6 volunteers given 1800 mg intra muscularly. Levels returned to normal in about two weeks. Transient elevations in creatine kinase were observed in all normal volunteers given the drug.

Atropine and Pralidoxime Chloride

When atropine and pralidoxime are used together, the signs of atropinization may occur earlier than might be expected when atropine is used alone.

Inadvertant Injection

The DuoDote Auto-Injector should be administered by emergency medical services personnel to treat organophosphorous poisoning. However, an injection might be given by mistake to someone who is not poisoned.

Studies have been conducted to evaluate the effect of atropine and pralidoxime on individuals in the absence of poisoning.

Atropine 2 mg IM, roughly the equivalent of one DuoDote Auto-Injector, when given to healthy male volunteers, is associated with minimal effects on visual, motor, and mental functions, though unsteadiness walking and difficulty concentrating may occur. Atropine reduces body sweating and increases body temperature, particularly with exercise and under hot conditions.

Atropine 4 mg IM, roughly the equivalent of two DuoDote Auto-Injectors, when given to healthy male volunteers, is associated with impaired visual acuity, visual near point accommodation, logical reasoning, digital recall, learning, and cognitive reaction time. Ability to read is reduced or lost. Subjects are unsteady and need to concentrate on walking. These effects begin about 15 minutes to one hour or more post-dose.

Atropine 6 mg IM, roughly the equivalent of three DuoDote Auto-Injectors, when given to healthy male volunteers, is associated with the effects described above plus additional central effects including poor coordination, poor attention span, and visual hallucinations (colored flashes) in many subjects. Frank visual hallucinations, auditory hallucinations, disorientation, and ataxia occur in some subjects. Skilled and labor-intense tasks are performed more slowly and less efficiently. Decision making takes longer and is sometimes impaired.

It is unclear if the results of the above studies can be extrapolated to other populations. In the elderly and patients with co-morbid conditions, the effects of ≥ 2 mg atropine on the ability to see, walk and think properly are unstudied; effects may be greater in susceptible populations.

Symptoms of pralidoxime overdose may include: dizziness, blurred vision, diplopia, headache, impaired accommodation, nausea, and slight tachycardia. Transient hypertension due to pralidoxime may last several hours.

Patients who are mistakenly injected with DuoDote should avoid potentially dangerous overheating, avoid vigorous physical activity, and seek medical attention as soon as feasible.




Manifestations of atropine overdose are dose-related and include flushing, dry skin and mucous membranes, tachycardia, widely dilated pupils that are poorly responsive to light, blurred vision, and fever (which can sometimes be dangerously elevated). Locomotor difficulties, disorientation, hallucinations, delirium, confusion, agitation, coma, and central depression can occur and may last 48 hours or longer. In instances of severe atropine intoxication, respiratory depression, coma, circulatory collapse, and death may occur.

The fatal dose of atropine is unknown. In the treatment of organophosphorous poisoning, doses as high as 1000 mg have been given. The few deaths in adults reported in the literature were generally seen using typical clinical doses of atropine often in the setting of bradycardia associated with an acute myocardial infarction, or with larger doses, due to overheating in a setting of vigorous physical activity in a hot environment.


It may be difficult to differentiate some of the side effects due to pralidoxime from those due to organophosphorous poisoning. Symptoms of pralidoxime overdose may include: dizziness, blurred vision, diplopia, headache, impaired accommodation, nausea, and slight tachycardia. Transient hypertension due to pralidoxime may last several hours.


For atropine overdose, supportive treatment should be administered. If respiration is depressed, artificial respiration with oxygen is necessary. Ice bags, a hypothermia blanket, or other methods of cooling may be required to reduce atropine-induced fever, especially in children. Catheterization may be necessary if urinary retention occurs. Since atropine elimination takes place through the kidney, urinary output must be maintained and increased if possible; intravenous fluids may be indicated. Because of atropine-induced photophobia, the room should be darkened.

A short-acting barbiturate or diazepam may be needed to control marked excitement and convulsions. However, large doses for sedation should be avoided because central depressant action may coincide with the depression occurring late in severe atropine poisoning. Central stimulants are not recommended.

Physostigmine, given as an atropine antidote by slow intravenous injection of 1 to 4 mg (0.5 to 1.0 mg in children) rapidly abolishes delirium and coma caused by large doses of atropine. Since physostigmine has a short duration of action, the patient may again lapse into coma after one or two hours, and require repeated doses. Neostigmine, pilocarpine, and methacholine are of little benefit, since they do not penetrate the blood-brain barrier.

Pralidoxime-induced hypertension has been treated by administering phentolamine 5 mg intravenously, repeated if necessary due to phentolamine's short duration of action. In the absence of substantial clinical data regarding use of phentolamine to treat pralidoxime-induced hypertension, consider slow infusion to avoid precipitous corrections in blood pressure.

What is atropine and pralidoxime (duodote)?

Atropine blocks the action of chemical called acetylcholine (ah see til KO leen), which may exist in high levels in the body after a poisoning. Atropine also stimulates the heart and reduces the secretions of the nose, mouth, and lungs to improve breathing.

Pralidoxime reverses muscle weakness or paralysis caused by a poison or nerve agent.

The combination of atropine and pralidoxime is used as an antidote to treat poisoning by a pesticide (insect spray) or a chemical that interferes with the central nervous system, such as nerve gas.

This medication is not effective as an antidote for all types of pesticide poisonings. You may need medications or additional treatments.

Atropine and pralidoxime may also be used for purposes not listed in this medication guide.

What is the most important information i should know about atropine and pralidoxime (duodote)?

If possible, before you receive atropine and pralidoxime, tell your doctor if you have heart disease, coronary artery disease, a heart rhythm disorder, high blood pressure, narrow-angle glaucoma, kidney disease, enlarged prostate, urination problems, a breathing disorder such as asthma or COPD, if you are allergic to any medication, or if you have recently had a heart attack.

Also tell your doctor if you are pregnant or breast-feeding.

In an emergency situation it may not be possible before you are treated to tell your caregivers about your health conditions or if you are pregnant or breast-feeding. Make sure any doctor caring for you afterward knows that you have received this medication.

What should i discuss with my health care provider before receiving atropine and pralidoxime (duodote)?

If possible, before you receive atropine and pralidoxime, tell your doctor if you have:

  • an allergy to any medication;
  • heart disease, coronary artery disease;
  • high blood pressure;
  • kidney disease;
  • asthma, COPD (chronic obstructive pulmonary disorder), bronchitis, emphysema, or other breathing problem;
  • a heart rhythm disorder;
  • narrow-angle glaucoma;
  • an enlarged prostate or urination problems; or
  • if you have recently had a heart attack.

FDA pregnancy category C. It is not known whether atropine and pralidoxime will harm an unborn baby. Tell your doctor if you are pregnant.

Atropine and pralidoxime can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

In an emergency situation, it may not be possible before you are treated with atropine and pralidoxime to tell your caregivers if you are pregnant or breast-feeding. Make sure any doctor caring for your pregnancy or your baby knows you have received this medication.

What should i avoid after receiving atropine and pralidoxime (duodote)?

Avoid becoming overheated or dehydrated during exercise and in hot weather. Atropine can decrease sweating and you may be more prone to heat stroke for a short time after receiving this medication.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.