Nokea
A patient has a drug level of 50 units/mL and the drug's half-life is 1 hour. If concentrations above 25 units/mL are considered toxic and no more drug is given, how long will it take for the blood level to reach the nontoxic range?
- A. 30 minutes
- B. 1 hour
- C. 2 hours
- D. 3 hours
Correct Answer: C
Rationale: Half-life is the time required for the serum concentration of a drug to decrease by 50%. After 1 hour, the serum concentration would be 25 units/mL (50/2). After 2 hours, the serum concentration would be 12.5 units/mL (25/2) and reach the nontoxic range.
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A 70-year-old patient has just received a drug that can cause sedation. What would be the priority nursing diagnosis for this patient?
- A. Noncompliance: Cost of the drug
- B. Deficient knowledge: Unfamiliar with drug therapy
- C. Risk for injury: Related to adverse effects of the drug
- D. Ineffective health maintenance: Need for medication
Correct Answer: C
Rationale: Sedation increases the risk of falls or injury, making 'Risk for injury' the priority diagnosis over knowledge deficits or compliance issues.
The tricyclic antidepressants should be prescribed cautiously in patients with:
- A. Eczema
- B. Asthma
- C. Diabetes
- D. Heart disease
Correct Answer: D
Rationale: TCAs can cause cardiac arrhythmias, necessitating caution in heart disease.
Patients need to be instructed regarding the drug interactions with St John's wort, including:
- A. MAO inhibitors
- B. Serotonin reuptake inhibitors
- C. Over-the-counter cough and cold medications
- D. All of the above
Correct Answer: D
Rationale: St John's wort interacts with MAOIs, SSRIs (risk of serotonin syndrome), and OTC drugs via CYP450 induction.
A nurse is preparing a teaching plan for a female client who has Bipolar disorder and a new prescription for Carbamazepine. Which of the following instructions should the nurse include in the teaching? (Select one that does not apply.)
- A. This medication can safely be taken during pregnancy.
- B. Eliminate grapefruit juice from your diet.
- C. You will need to have a complete blood count and carbamazepine levels drawn periodically.
- D. You'll your provider if you develop a rash.
Correct Answer: A
Rationale: Grapefruit juice interacts, blood counts monitor toxicity, rash signals reaction, and driving caution addresses sedation.
James is a 52-year-old overweight smoker taking theophylline for his persistent asthma. He tells his provider he is going to start the Atkin's diet for weight loss. The appropriate response would be:
- A. Congratulate him on making a positive change in his life
- B. Recommend he discuss this with his provider since the Atkin's diet increases the risk of theophylline toxicity
- C. Tell him the Atkin's diet has no effect on theophylline
- D. Suggest adding a steroid inhaler to manage asthma during the diet
Correct Answer: B
Rationale: The Atkin's diet (high-fat, low-carb) can increase theophylline levels, risking toxicity ; simple congratulations or dismissal overlook this interaction.