Atropine/Pralidoxime

Atropine/pralidoxime is used for the treatment of poisoning by organophosphorus nerve agents as well as organophosphorus insecticides in adults and pediatric patients weighing more than 41 kg (90 pounds).

Atropine/pralidoxime is available under the following different brand names: ATNAA and DuoDote.

Dosages of Atropine/Pralidoxime:

Dosage Forms and Strengths

Intramuscular (IM) Autoinjector

• atropine (2.1mg/0.7mL) plus pralidoxime chloride (600mg/2mL) in 2 separate chambers; when activated, sequentially administers both drugs IM through a single needle

Dosage Considerations – Should be Given as Follows:

Organophosphate Poisoning

• Indicated for the treatment of poisoning by organophosphorus nerve agents as well as organophosphorus insecticides in adults and pediatric patients weighing more than 41 kg (90 pounds)
• Adults and children weighing over 41 kg: 2.1 mg atropine/0.7 mL + 600 mg pralidoxime/2 mL intramuscularly (IM)
• Maximum dose: Not to exceed 3 injections unless medical care support is available
• 3 autoinjectors should be available for use in each patient (including healthcare providers) at risk for organophosphorus poisoning; use 1 for mild symptoms plus 2 more for severe symptoms

Mild symptoms

• 2 or more mild symptoms: 1 injection IM; if after 10-15 min there are no severe symptoms experienced, no further injections are necessary
• Additional doses: If, at any time following the first injection, the patient develops any of the severe symptoms, administer 2 additional IM injections in rapid succession
• Mild symptoms: Slow heart rate, chest tightness, breathing difficulties, blurred vision, increased salivation (e.g., sudden drooling), constricted pupils, nausea or vomiting, runny nose, stomach cramps (acute onset), salivation, teary eyes, wheezing/coughing, tremors/muscular twitching, airway secretions increased

Severe symptoms

• Any severe symptom listed below: 3 injections IM in rapid succession
• Severe symptoms: Confused/strange behavior, involuntary urination/defecation, muscular twitching/generalized weakness (severe), severe breathing difficulties or copious secretion from lung or airway, convulsions, unconsciousness
• Children weighing less than 41 kg: Safety and efficacy not established

Dosing Modifications

• Renal impairment
• Pralidoxime can cause decreased renal function
• Patients with severe renal impairment may require less frequent doses after the initial dose
• Hepatic impairment
• Patients with severe hepatic impairment may require less frequent doses after the initial dose

Dosing Considerations

• Three autoinjectors should be available for use in each patient (including healthcare providers) at risk for organophosphorus poisoning; one (1) for mild symptoms plus two (2) more for severe symptoms; note that individuals may not have all symptoms included under mild or severe symptom category
• Only administer the drug to patients experiencing symptoms of organophosphorus poisoning in a situation where exposure is known or suspected; autoinjector is intended as an initial treatment of symptoms of organophosphorus nerve agent or insecticide poisonings as soon as symptoms appear; definitive medical care should be sought immediately
• The autoinjector should be administered by healthcare providers with adequate training in recognition and treatment of nerve agent or insecticide intoxication
• Close supervision of all treated patients is indicated for at least 48 to 72 hours
• Older individuals may be more susceptible to atropine effects

Side effects of atropine/pralidoxime include:

• Injection site reactions (muscle tightness, pain)
• Atropine
• Dry mouth
• Blurred vision
• Dry eyes
• Sensitivity to light (photophobia)
• Confusion
• Headache
• Dizziness
• Pralidoxime
• Vision changes
• Dizziness, headache
• Drowsiness
• Nausea
• Fast heart rate
• Increased blood pressure
• Muscular weakness
• Dry mouth
• Vomiting
• Rash
• Dry skin
• Hyperventilation
• Decreased renal function
• Manic behavior
• Transient elevation of liver function tests

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.

• Atropine/pralidoxime has no listed severe interactions with other drugs.

Serious interactions of atropine/pralidoxime include:

• pramlintide

Atropine/pralidoxime has moderate interactions with at least 90 different drugs.

Mild interactions of atropine/pralidoxime include:

• dimenhydrinate
• donepezil
• galantamine

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

Warnings

This medication contains atropine/pralidoxime. Do not take ATNAA or DuoDote if you are allergic to atropine/pralidoxime or any ingredients contained in this drug.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.

Contraindications

• None

Effects of Drug Abuse

• No information is available

Short-Term Effects

• See "What Are Side Effects Associated with Using Atropine/Pralidoxime?”

Long-Term Effects

• See "What Are Side Effects Associated with Using Atropine/Pralidoxime?”

Cautions

• Caution in patients with known cardiovascular disease or cardiac conduction problems
• May inhibit sweating and lead to hyperthermia; avoid excessive exercise and heat exposure
• Caution in susceptible individuals at risk for acute glaucoma
• Caution in patients with bladder outflow obstruction owing to the risk of urinary retention
• Caution with partial pyloric stenosis because of risk of complete pyloric obstruction
• May cause inspiration of bronchial secretions and formation of dangerous viscid plugs in individuals with chronic lung disease; monitor respiratory status
• Individuals should not rely solely upon atropine and pralidoxime to provide complete protection from chemical nerve agents and insecticide poisoning (e.g., primary protection is the wearing of protective garments)
• Elderly individuals may be more susceptible to the effects of atropine
• Patients with organophosphorus nerve agent or organophosphorus insecticide poisoning who have received atropine/pralidoxime may exhibit accelerated reversal of the neuromuscular blocking effects of succinylcholine and mivacurium; monitor for neuromuscular effects with concomitant succinylcholine or mivacurium use

Pregnancy and Lactation

Atropine readily crosses the placental barrier and enters the fetal circulation. There are no adequate data on developmental risks associated with the use of atropine, pralidoxime, or the combination of the two in pregnant women. Consult your doctor.

Atropine has been reported to be excreted in human milk. It is unknown whether pralidoxime is excreted in human milk. Consult your doctor before breastfeeding.