Final answer:
The effectiveness of carvedilol (Coreg) in an African-American patient might be compromised due to its effects on vascular resistance, with varying responses to beta-blockers in different populations due to genetic factors related to the renin-angiotensin-aldosterone system.
Step-by-step explanation:
The nurse understands that a medication such as carvedilol (Coreg) may not be effective in an African-American patient because of its effects on vascular resistance. Carvedilol is a type of beta-blocker which works by blocking beta receptors, leading to decreased cardiac output due to a slower heart rate and reduced myocardial contractility.
In some studies, African-American patients may respond differently to beta-blockers possibly due to genetic factors that influence the renin-angiotensin-aldosterone system ultimately affecting vascular resistance differently. It is important to note that while the effectiveness of beta-blockers can vary among individuals, carvedilol and other medications in the same class remain a vital part of treatment for conditions like hypertension and heart failure. Health care professionals should tailor treatment plans to individual patient needs considering evidence-based practices and patient-specific factors, including race and the potential for variations in drug efficacy.