Hypertension Pharmacology & Management (JNC-8)

Vocabulary flashcards covering definitions, mechanisms, drug classes, adverse effects, and clinical considerations related to hypertension management per JNC-8 guidelines.

Hypertension

Chronically elevated arterial blood pressure that increases cardiovascular risk.

JNC-8 BP Threshold (≥60 y)

Initiate drug therapy when BP is 150/90 mm Hg or higher in patients aged 60 years or older.

JNC-8 BP Threshold (<60 y or CKD/Diabetes)

Begin treatment at 140/90 mm Hg for adults under 60 years or any age with CKD or diabetes.

Blood Pressure (BP) Formula

BP = Cardiac Output (CO) × Systemic Vascular Resistance (SVR).

Primary (Essential) Hypertension

High BP with no identifiable cause; accounts for ~90 % of cases.

Secondary Hypertension

Elevated BP due to an identifiable condition (e.g., renal disease); ~10 % of cases.

Cardiac Output (CO)

Volume of blood the heart pumps per minute; component of BP.

Systemic Vascular Resistance (SVR)

Resistance blood encounters in systemic circulation; component of BP.

Diuretics

Drugs that reduce plasma/extracellular fluid volume to lower BP; thiazides are most common.

Adrenergic Drugs

Agents that modify sympathetic nervous system activity to decrease BP.

Vasodilators

Drugs that directly relax vascular smooth muscle, lowering SVR and afterload.

ACE Inhibitors (-pril)

Block angiotensin-converting enzyme, preventing angiotensin II formation and aldosterone release.

Angiotensin II Receptor Blockers (ARBs, ‑sartan)

Block angiotensin II receptors, inhibiting vasoconstriction and aldosterone secretion.

Calcium Channel Blockers (CCBs)

Prevent calcium entry into vascular smooth muscle, causing vasodilation and reduced BP.

Direct Renin Inhibitors

Agents that block renin activity, suppressing the RAAS cascade to lower BP.

Alpha2 Receptor Agonists

Central agents (e.g., clonidine) that reduce sympathetic outflow and norepinephrine release.

Alpha1 Receptor Blockers

Peripheral drugs (e.g., doxazosin) that dilate arteries/veins and relieve BPH symptoms.

Beta Receptor Blockers

Agents (e.g., metoprolol) that decrease heart rate and renin secretion via β1 blockade.

Dual-Action Alpha1/Beta Blockers

Drugs (e.g., labetalol) combining vasodilation with heart-rate reduction.

Orthostatic Hypotension

Drop in BP upon standing; common adverse effect of adrenergic drugs.

First-Dose Syncope

Transient fainting after initial antihypertensive dose, especially with alpha blockers.

Rebound Hypertension

Acute BP rise when antihypertensives are stopped abruptly.

Dry, Nonproductive Cough

Classic, reversible adverse effect of ACE inhibitors.

Hyperkalemia

Elevated serum potassium; risk with ACE inhibitors and less often with ARBs.

Angioedema

Rare, potentially fatal facial/airway swelling linked to ACE inhibitors.

Captopril

ACE inhibitor that is not a prodrug; useful in liver impairment.

Enalapril

Only ACE inhibitor available in both oral and intravenous forms.

Renin-Angiotensin-Aldosterone System (RAAS)

Hormonal cascade that raises BP via vasoconstriction and sodium/water retention.

Thiazide Diuretics

First-line diuretic class for hypertension; lowers preload and CO.

Sodium Nitroprusside

IV vasodilator reserved for hypertensive emergencies.

Preload

Volume/pressure in ventricles at end-diastole; ACE inhibitors reduce it.

Afterload

Resistance the heart must overcome to eject blood; vasodilators lower it.

Postural Hypotension

Synonym for orthostatic hypotension; instruct patients to rise slowly.

Medication Adherence

Taking antihypertensive drugs exactly as prescribed to prevent complications.

Lifestyle Modification

Diet, weight control, exercise, stress reduction, smoking cessation to aid BP control.