While ATNAA can be administered to all individuals with a life-threatening exposure to organophosphorous nerve agents, it should be administered with extreme caution to individuals with the following disorders when the symptoms of nerve agent poisoning are less severe: individuals who are hypersensitive to any component of the product, disorders of heart rhythm such as atrial flutter, severe narrow angle glaucoma, pyloric stenosis, or prostatic hypertrophy.
More than one dose of ATNAA, to a maximum of three doses, may be necessary, especially when exposure is massive or symptoms are severe (see DOSAGE AND ADMINISTRATION). Children are more susceptible than adults to the toxic effects of anticholinergic agents.
Severe difficulty in breathing requires artificial respiration in addition to the use of the ATNAA.
Pralidoxime is not effective in the treatment of poisoning due to phosphorus, inorganic phosphates, or organophosphates not having anticholinesterase activity.
General: The desperate condition of the organophosphorous-poisoned patient will generally mask such minor signs and symptoms of atropine and pralidoxime treatment as have been noted in normal subjects.
Because pralidoxime is excreted in the urine, a decrease in renal function will result in increased blood levels of the drug.
The ATNAA should be used with caution in all individuals over 40 years of age. Conventional systemic doses may precipitate acute glaucoma in susceptible patients, convert partial organic pyloric stenosis into complete pyloric obstruction, precipitate urinary retention in patients with prostatic hypertrophy, or cause inspiration of bronchial secretions and formation of dangerous viscid plugs in patients with chronic lung disease.
Information for Patients: Appropriate steps must be taken to insure that personnel understand the indications for, and use of, the ATNAA, including review of symptoms of poisoning and operation of the ATNAA (see DOSAGE AND ADMINISTRATION and Patient Instruction Sheet).
Drug Interactions: When atropine and pralidoxime are used together, the signs of atropinization (flushing, mydriasis, tachycardia, dryness of the mouth and nose) may occur earlier than might be expected when atropine is used alone because pralidoxime may potentiate the effect of atropine.2,3,4
The following precautions should be kept in mind in the treatment of anticholinesterase poisoning, although they do not bear directly on the use of atropine and pralidoxime. Since barbiturates are potentiated by the anticholinesterases, they should be used cautiously in the treatment of convulsions. Morphine, theophylline, aminophylline, succinylcholine, reserpine, and phenothiazine-type tranquilizers should be avoided in treating personnel with organophosphorous poisoning.
Carcinogenesis, Mutagenesis, Impairment of Fertility: No reports regarding the potential of atropine or pralidoxime chloride for carcinogenesis, mutagenesis, or impairment of fertility have been published in the literature. Since the ATNAA is indicated for short-term emergency use only, no investigations of these aspects have been conducted.
Pregnancy: Teratogenic Effects - Pregnancy Category C: Adequate animal reproduction studies have not been conducted with atropine, pralidoxime,or the combination. It is not known whether pralidoxime or atropine can cause fetal harm when administered to a pregnant woman or if these agents can affect reproductive capacity. The ATNAA should be administered to a pregnant woman only if clearly needed.
Nursing Mothers: It is not known whether these drugs are excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when the ATNAA is administered to a nursing woman.
Pediatric Use: Safety and effectiveness in pediatric patients have not been established.