Week 7: Calcium Channel Blockers

Question 1

Dihydropyridine - Nifedipine (Procardia) and Amlodipine (Norvasc) MOA and indication

Answer 1

• inhibit calcium ions from entering cell membranes in the peripheral vascular system
• no effect on the heart (no depression of SA/AV nodes)
• potent vasodilators
• relaxes the smooth muscles (directly affects muscle tone) - makes vessels more leaky

indication: hypertension, CAD/ exertional angina

Question 2

Dihydropyridines cautions/contraindications

Answer 2

• Never use in patients with heart failure, peripheral edema, unstable angina
• Ok to use in pregnancy

Question 3

Dihydropyridine ADRs

Answer 3

• Headache & peripheral edema most common
• gingival hyperplasia, nausea
• 1st dose effect: flushing, dizziness, H/A, hypotension, reflex tachycardia

Question 4

Why are calcium channel blockers (and possibly ARBs) more appropriate HTN drugs to use in African American patients?

Answer 4

African Americans:

• have less angiotensin II
• RAAS system is not as efficient
• have higher levels of intracellular calcium
• have a higher risk for angioedema

Question 5

Non-Dihydropyridine - Verapamil & Diltiazem (Cardizem) MOA

Answer 5

Inhibit calcium ions from entering the cell membranes
- affect the smooth muscle/myocardial cells in the heart
- has a highly negative ionotropic effect and slightly negative chronotropic effect
Also affects smooth muscle in the GI tract, which can lead to decreased peristalsis

Question 6

Non-Dihydropyridines Indications for use

Answer 6

• Atrial fibrillation (with HTN)
• SVT
• Angina (stable & exertional)
• class 4 antiarrhythmic because of its ionotropic and chronotropic effects

Question 7

Non-dihydropyridine (Verapamil/Diltiazem) cautions/ contraindications

Answer 7

• avoid use in heart failure/edema (more cardiac depression/negative effects on SA/AV nodes= reduces HR and contractility)
• avoid in ventricular dysfunction and in SA/AV nodal conduction disturbances (2nd degree block)
• contraindicated in < 90 Systolic BP
• NO preg/lactation

Question 8

Dihydropyridine and Non-Dihydropyridine ADRs

Answer 8

• edema
• headache
• gingival hyperplasia
• constipation (verapamil)
• bradycardia

Question 9

Verapamil/Diltiazem Patient Education:

Answer 9

• avoid NSAIDS, alcohol use, being in a jacuzzi alone
• GI reflux disease symptoms can get worse after starting this medication
• call doc for signs of HF (dyspnea, dizz, nausea, swelling hands/feet, dec UO)