Dihydropyridines (amlodipine, nifedipine) primarily cause peripheral vasodilation and may produce reflex tachycardia and peripheral edema.
Before you read
Test yourself first: 5 questions
Question 1 of 5
A client is prescribed a calcium channel blocker and reports constipation. The nurse teaches:
Answer: B. Constipation is a common side effect of some calcium channel blockers (e.g., verapamil) — increase fiber, fluids, and activity, and use a stool softener if needed. Do not stop the drug abruptly.
Question 2 of 5
A client with hypertension is prescribed amlodipine, a calcium channel blocker. The nurse should teach the client to report which common side effect?
Answer: A. Dihydropyridine calcium channel blockers such as amlodipine cause peripheral vasodilation, which commonly produces peripheral edema (especially ankle swelling), flushing, and headache. The client should report swelling of the ankles and feet. Amlodipine does not typically cause a productive cough, increased urine output, or significant bradycardia (unlike non-dihydropyridines).
Question 3 of 5
A client taking a calcium channel blocker (e.g., amlodipine) should avoid:
Answer: B. Grapefruit juice inhibits metabolism of many calcium channel blockers, increasing drug levels and the risk of hypotension. Teach to avoid grapefruit.
Question 4 of 5
A client with a subarachnoid hemorrhage from a ruptured aneurysm is prescribed nimodipine. The nurse understands this drug is given to:
Answer: A. Nimodipine is a calcium channel blocker used after subarachnoid hemorrhage to reduce cerebral vasospasm, which can cause delayed ischemia and stroke. The nurse monitors blood pressure because nimodipine can cause hypotension. It is not given to dissolve clots, to directly stop seizures, or to increase intracranial pressure.
Question 5 of 5
The nurse is administering IV verapamil to a client with a rapid supraventricular tachycardia. Which assessment is most important during administration?
Answer: B. Verapamil is a non-dihydropyridine calcium channel blocker with strong negative chronotropic and dromotropic effects; it can cause bradycardia, heart block, and hypotension. Continuous cardiac monitoring and frequent blood pressure assessment are essential during IV administration. Monitoring deep tendon reflexes, pupil size, or bowel sounds is not the priority for this drug.
Keep the streak going with more questions like these, each with a full rationale.
What is calcium channel blockers?
They treat hypertension, angina, and certain dysrhythmias. Memory aid: dihydropyridines (-dipine) mainly relax vessels, while diltiazem and verapamil also slow the heart.
Key points to remember
- Dihydropyridines (amlodipine, nifedipine) primarily cause peripheral vasodilation and may produce reflex tachycardia and peripheral edema.
- Verapamil and diltiazem (non-dihydropyridines) slow the heart rate and AV conduction and can cause bradycardia.
- Verapamil commonly causes constipation.
- Grapefruit juice raises blood levels and increases toxicity risk.
- Combining non-dihydropyridine agents with beta blockers increases the risk of profound bradycardia and heart block.
- Common effects include hypotension, headache, dizziness, and flushing.
Signs & symptoms
- Peripheral edema, flushing
- Headache, dizziness, ↓ HR
Nursing priorities
- Check apical pulse and blood pressure before administration; hold for bradycardia or hypotension per parameters.
- Monitor for peripheral edema, especially with amlodipine and nifedipine.
- Assess for constipation with verapamil and encourage fluids and fiber.
- Monitor for additive bradycardia when given with beta blockers or digoxin.
- Implement fall precautions due to hypotension and dizziness.
Patient teaching
- Avoid grapefruit and grapefruit juice while taking this medication.
- Rise slowly to prevent dizziness, and report ankle swelling.
- Increase fiber and fluids to prevent constipation if you take verapamil.
Red flags: report now
- Bradycardia, new heart block, or symptomatic hypotension, especially with verapamil or diltiazem.
- Signs of worsening heart failure such as crackles, edema, and shortness of breath.
- Profound bradycardia when combined with a beta blocker.
- Severe hypotension after administration.
References
Clinical references for this topic
