Ca Channel Blockers Flashcards
What effect will Ca channel blockers have on the myocardium?
Negative inotropy and negative chronotropy.
For what condition would Ca channel blockers’ effects on the hear be detrimental?
CHF
What effect will Ca channel blockers have on the vasculature?
Vasodilation –> dec BP
Classify the four Ca channel blockers by their myocardial and vascular effects.
Verapamil: 95% heart and 5% vasculature (1st CCB)
Diltiazem: 50% heart and 50% vasculature
Nifedipine: 5% heart and 95% vasculature
Amlodipine: 1% heart and 99% vasculature
What is the primary use of verapamil and diltiazem?
Rate control in atrial fibrillation
What is the primary use of nifedipine and amlodipine?
Anti-hypertensives
What is a major adverse effect of verapamil and why does it occur?
constipation –> blocks Ca channels in colon
When prescribing verapamil or diltiazem, what three things are important to monitor?
HR, BP, ECG
How is verapamil dosed and distributed?
Immediate release –> TID
Sustained release –> qHS (circadian dosing)
What is important to instruct patients on when prescribing sustained release medications?
Do not crush or break tablets
What are three forms in which diltiazem is available and how is each dosed?
Immediate release: QID
Sustained release: BID
Continuous dosing: QD
What is the most significant adverse effect of nifedipine?
non-cardiogenic peripheral edema
Aside from its most significant adverse effect, what are two other adverse effects of nifedipine?
flushing/rash gingival hyperplasia (overgrowth of gums --> rare
What are two forms in which nifedipine is available and how is each dosed?
Immediate release: TID
Sustained release: QD
Why is immediate release nifedipine rarely used?
Increased cardiovascular morbidity and mortality
