Atropine Sulfate

ATROPINE SULFATE- atropine sulfate injection, solution
American Regent, Inc.

1 INDICATIONS AND USAGE

Atropine Sulfate Injection, USP, is indicated for temporary blockade of severe or life threatening muscarinic effects, e.g., as an antisialagogue, an antivagal agent, an antidote for organophosphorus or muscarinic mushroom poisoning, and to treat bradyasystolic cardiac arrest.

2 DOSAGE AND ADMINISTRATION

2.1 General Administration

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Do not administer unless solution is clear and seal is intact. Each vial is intended for single dose only. Discard unused portion.

For Intravenous administration.

Titrate based on heart rate, PR interval, blood pressure and symptoms.

2.2 Adult Dosage

Table 1: Recommended Dosage

Use	Dose (adults)	Repeat
Antisialagogue or other antivagal	0.5 to 1 mg	1 to 2 hours
Organophosphorus or muscarinic mushroom poisoning	2 to 3 mg	20 to 30 minutes
Bradyasystolic cardiac arrest	1 mg	3 to 5 minutes; 3 mg maximum total dose

2.3 Pediatric Dosage

Dosing in pediatric populations has not been well studied. Usual initial dose is 0.01 to 0.03 mg/kg.

2.4 Dosing in Patients with Coronary Artery Disease

Limit the total dose of atropine sulfate to 0.03 to 0.04 mg/kg [see Warnings and Precautions (5.1)].

3 DOSAGE FORMS AND STRENGTHS

Injection: supplied as a clear, colorless solution in a 1 mL glass vial in the following concentrations:

• 0.4 mg/mL: containing 0.4 mg of atropine sulfate monohydrate equivalent to 0.332 mg of atropine.
• 1 mg/mL: containing 1 mg atropine sulfate monohydrate equivalent to 0.83 mg of atropine.

4 CONTRAINDICATIONS

None.

5 WARNINGS AND PRECAUTIONS

5.1 Tachycardia

When the recurrent use of atropine is essential in patients with coronary artery disease, the total dose should be restricted to 2 to 3 mg (maximum 0.03 to 0.04 mg/kg) to avoid the detrimental effects of atropine-induced tachycardia on myocardial oxygen demand.

5.2 Acute Glaucoma

Atropine may precipitate acute glaucoma.

5.3 Pyloric Obstruction

Atropine may convert partial organic pyloric stenosis into complete obstruction.

5.4 Complete Urinary Retention

Atropine may lead to complete urinary retention in patients with prostatic hypertrophy.

5.5 Viscid Plugs

Atropine may cause inspissation of bronchial secretions and formation of viscid plugs in patients with chronic lung disease.

6 ADVERSE REACTIONS

The following adverse reactions have been identified during post-approval use of atropine sulfate. 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.

Most of the side effects of atropine are directly related to its antimuscarinic action. Dryness of the mouth, blurred vision, photophobia and tachycardia commonly occur. Anhidrosis can produce heat intolerance. Constipation and difficulty in micturition may occur in elderly patients. Occasional hypersensitivity reactions have been observed, especially skin rashes which in some instances progressed to exfoliation.

7 DRUG INTERACTIONS

7.1 Mexiletine

Atropine Sulfate Injection decreased the rate of mexiletine absorption without altering the relative oral bioavailability; this delay in mexiletine absorption was reversed by the combination of atropine and intravenous metoclopramide during pretreatment for anesthesia.

8 USE IN SPECIFIC POPULATIONS

8.1 Pregnancy

Pregnancy

Risk Summary

There are risks to the mother and fetus associated with untreated severe or life-threatening muscarinic events (see Clinical Considerations). Available data from published observational studies on atropine use in pregnant women are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes (see Data). Animal reproduction studies have not been conducted with atropine.

Clinical Considerations

Disease-associated maternal and/or embryo/fetal risk

Severe or life-threatening muscarinic events such as acute organophosphate poisoning and symptomatic bradycardia are medical emergencies in pregnancy which can be fatal if left untreated. Life-sustaining therapy for the pregnant woman should not be withheld because of concerns regarding the effects of atropine on the fetus.

Data

Human Data Atropine crosses the placenta [see Clinical Pharmacology (12.3)]. No adequate and well-controlled studies are available regarding use of atropine in pregnant women. In a cohort study of 401 pregnancies in the first trimester and 797 pregnancies in the second or third trimester, atropine use was not associated with an increased risk of congenital malformation. In a surveillance study, 381 newborns were exposed to atropine during the first trimester; 18 major birth defects were observed when 16 were expected. No specific pattern of major birth defects was identified. In another surveillance study of 50 pregnancies in the first trimester, atropine use was not associated with an increased risk of malformations. Methodological limitations of these observational studies including the inability to control for the dosage and timing of atropine exposure, underlying maternal disease, or concomitant maternal drug use, cannot definitively establish or exclude any drug associated risk during pregnancy.

8.2 Lactation

Risk Summary

Trace amounts of atropine have been reported in human milk after oral intake. There are no available data on atropine levels in human milk after intravenous injection, the effects on the breastfed infant, or the effects on milk production.

Clinical Considerations

Minimizing exposure The elimination half-life of atropine is more than doubled in children less than 2 years of age [see Clinical Pharmacology (12.3)]. To minimize potential infant exposure to Atropine Sulfate Injection, a woman may pump and discard her milk for 24 hours after use before resuming to breastfeed her infant.

8.4 Pediatric Use

Recommendations for use in pediatric patients are not based on clinical trials.