Calcium Channel Blockers

Every question here, with the answer

1. A client taking amlodipine for hypertension tells the nurse, "I feel much better, so I plan to stop my blood pressure pill today." What should the nurse explain?

   1. Stopping it will only cause mild constipation.
   2. Stopping a calcium channel blocker abruptly may cause chest pain, so talk to your provider first.
   3. You can stop it if you switch to grapefruit juice each morning.
   4. Stopping suddenly is safe once blood pressure is normal.

   Answer: Stopping a calcium channel blocker abruptly may cause chest pain, so talk to your provider first.

   The section warns that abrupt discontinuation of calcium channel blockers may cause chest pain, so the client should not stop the drug on their own. Grapefruit juice affects these drugs rather than replacing them, and constipation is an adverse effect of taking the drug, not of stopping it.

2. A client starting a calcium channel blocker asks how to prevent the stomach upset they had with the first dose. What should the nurse teach?

   1. Take the medication with food.
   2. Skip the dose on days you feel nauseated.
   3. Take the medication with grapefruit juice.
   4. Take the medication only at bedtime on an empty stomach.

   Answer: Take the medication with food.

   Client teaching says to take the medication with food to avoid GI upset, nausea, and vomiting. Grapefruit juice can affect the action of certain calcium channel blockers, and an empty stomach or skipping doses is not recommended.

3. A nurse is teaching a client who is taking a calcium channel blocker. Which side effects should the client report to the health care provider? Select all that apply.

   1. Leg swelling
   2. Severe headaches
   3. Flushing
   4. Improved exercise tolerance
   5. Lightheadedness

   Answer: Leg swelling, Severe headaches, Flushing, Lightheadedness

   The client should report severe headaches, dizziness, lightheadedness, flushing, nausea, and leg swelling. Improved exercise tolerance is not an adverse effect.

4. The nurse reviews the history of a client with a new prescription for a calcium channel blocker. Which findings are contraindications? Select all that apply.

   1. History of pulmonary congestion
   2. Stage 1 hypertension
   3. Sick sinus syndrome without an artificial pacemaker
   4. Severe hypotension
   5. History of myocardial infarction

   Answer: History of pulmonary congestion, Sick sinus syndrome without an artificial pacemaker, Severe hypotension, History of myocardial infarction

   Contraindications include sick sinus syndrome (unless the client has an artificial pacemaker), severe hypotension, and a history of myocardial infarction or pulmonary congestion. Hypertension is what the drug treats.

5. During a medication history, a client on diltiazem mentions taking an herbal supplement for mood. Which supplement should the nurse flag for a possible interaction?

   1. St. John's wort
   2. Food taken with each dose
   3. A daily multivitamin with no herbs
   4. Plain water with meals

   Answer: St. John's wort

   Many medications and herbal supplements, such as St. John's wort, interact with calcium channel blockers, so the nurse monitors for interactions. Taking the drug with food is recommended, not a concern.

6. A client asks why verapamil, a nondihydropyridine, is used to control their fast heart rate. Which explanation is accurate?

   1. It increases calcium entry into heart cells.
   2. It inhibits the SA and AV nodes, slowing conduction and heart rate.
   3. It speeds up conduction through the AV node.
   4. It works only on the blood vessels of the legs.

   Answer: It inhibits the SA and AV nodes, slowing conduction and heart rate.

   Nondihydropyridines inhibit the sinoatrial and AV nodes, slowing cardiac conduction and heart rate and decreasing oxygen demand. Calcium channel blockers block calcium from entering cells rather than increasing it, and they slow conduction rather than speeding it.