Comprehensive exams for Mental Health Q 99



Which of the following drugs should Nurse Mary prepare to administer to a client with a toxic acetaminophen (Tylenol) level?
  
     A. Deferoxamine mesylate (Desferal)
     B. Succimer (Chemet)
     C. Flumazenil (Romazicon)
     D. Acetylcysteine (Mucomyst)
    
    

Correct Answer: D. Acetylcysteine (Mucomyst)

The antidote for acetaminophen toxicity is acetylcysteine. It enhances conversion of toxic metabolites to nontoxic metabolites. Acetaminophen (N-acetyl-para-aminophenol, paracetamol, APAP) toxicity is common primarily because the medication is so readily available, and there is a perception that it is very safe. More than 60 million Americans consume acetaminophen on a weekly basis. All patients with high levels of acetaminophen need admission and treatment with N-acetyl-cysteine (NAC). This agent is fully protective against liver toxicity if given within 8 hours after ingestion.

Option A: Deferoxamine mesylate is the antidote for iron intoxication. Desferal is indicated for the treatment of acute iron intoxication and chronic iron overload due to transfusion-dependent anemias. Desferal is an adjunct to, and not a substitute for, standard measures used in treating acute iron intoxication, which may include the following: induction of emesis with syrup of ipecac; gastric lavage; suction and maintenance of a clear airway; control of shock with intravenous fluids, blood, oxygen, and vasopressors; and correction of acidosis.
Option B: Succimer is an antidote for lead poisoning. Succimer is an oral heavy metal chelating agent used to treat lead and heavy metal poisoning. Succimer has been linked to a low rate of transient serum aminotransferase elevations during therapy, but its use has not been linked to cases of clinically apparent liver injury with jaundice. Succimer does not significantly chelate essential metals such as zinc, copper, or iron, and its specificity, safety and oral availability make it preferable to other chelating agents for treating lead poisoning such as Ca-EDTA which must be given intravenously and dimercaprol (British anti-Lewisite [BAL) which requires intramuscular administration.
Option C: Flumazenil reverses the sedative effects of benzodiazepines. Flumazenil is a benzodiazepine antagonist. Flumazenil is also indicated for the management and treatment of benzodiazepine overdose in adults. It is useful in reversing coma due to benzodiazepine overdose. Flumazenil is more effective in reversing sedation or coma in patients with benzodiazepine intoxication rather than in patients with multiple drug overdoses.