A patient taking a calcium channel blocker is seen in the clinic and diagnosed with drug toxicity. When collecting the nursing history, what finding would indicate the likely cause of this drug toxicity?

Question

A) Intake of alcohol
B) The use of eggs in the diet
C) The ingestion of grapefruit juice
D) Intake of aged cheese

Answer 1

C
Feedback:
The calcium channel blockers are a class of drugs that interact with grapefruit juice. When grapefruit juice is present in the body, the concentrations of calcium channel blockers increase, sometimes to toxic levels. Advise patients to avoid drinking grapefruit juice taking a calcium channel blocker. If a patient on a calcium channel blocker reports toxic effects, ask whether he or she is drinking grapefruit juice. Use of alcohol could be important if the patient was ingesting large amounts, but that would not be the most likely cause of drug toxicity. Eggs and cheese should not exert any food–drug interaction.