Antihypertensive Flashcards
Baroreceptor Reflex
1) system senses pressure
2) parasympathetic bradycardia
3) sympathetic tachycardia
4) sympathetics increase epi and norepi from adrenals
(not useful for controlling blood pressure)
Filtration Properties
120ml/min 1-2ml/min lost 98% Na+ re absorption -70%in Proximal Tubule -25% in Thick ascending limb -5% in Distal Tubule
Loop Diuretic Mechanism
Blockade of Na+ transport in thick ascending limb
Increase waterloss
POWERFUL diuresis
can reset impaired renal function
venodilation
generally TOO POWERFUL but useful in RENAL PROBLEMS
Loop Diuretic Drugs
Ethacryinic Acid (rare and only non-sulphonamide)
Furosemide
Bumetanide
Torsemide
Furosemide
Loop Diuretic: most common, oral, short duration
Bumetanide
Loop Diuretic: similiar to Furosemide with increased potency
Torsemide
Loop Diuretic: similiar to Furosemide with increased potency
Thiazide Diuretic Mechanism
block reabsorption in distal tubule
SLIGHT diuresis
active orally
sustained action
USEFUL in people with NORMAL RENAL FUNCTION
(poor efficacy in impaired renal function)
African Americans have best response
Thiazide Diuretic Drugs
Chlorthiazide Hydrochlorthiazide Clorthalidone Metolazone Indapamide
Chlorthiazide
Thiazide Diuretic: low bioaviliability
Hydrochlorthiazide
Thiazide Diuretic: commonly used
Clorthalidone
Thiazide Diuretic: slowly absorbed, long duration
Metolazone
Thiazide Diuretic: can be used in reduced renal function
Indapamide
Thiazide Diuretic: prominent vasodilation
Thiazide Diuretic Side Effects
hypokalemia + metabolic acidosis
Hyponatremia
increased serum glucose, cholesterol, triglycerides
Potassium Sparing Diuretic Mechanism
WEAK diuresis
No potassium excretion
No hypokalemia
Aldosterone Antagonists and Na+ permeability inhibitors
Aldosterone Antagonists
Block alderstone receptors
DECREASE MORTALITY
can cause hyperkalemia
Spironolactone, Eplerenone
Spironolactone
Aldosterone Antagonists: can cause gynecomastia
Eplerenone
Aldosterone Antagonists: no gynecomastia
Na+ Permeability Inhibitors
block reabsorption in end of distal tubulecan cause hyperkalemia
Triamterene
Amiloride, Triamterene
Amiloride
Na+ Permeability Inhibitor: Renal metabolism
Triamterene
Na+ Permeability Inhibitor: Hepatic metabolism
Angiotensin II
Increased peripheral resistance, increased blood volume, increased sympathetic activity
Bradykinin
increased vasodilation through increased NO and increased prostaglandins
ACE Inhibitor Mechanism
Blocks angiotensin converting enzyme (decreased Angiotensin II and increased Bradykinin)
In LV failure NO decreased BP w/ increased CO
In normal heart decreased BP w/ NO change in CO
Improves pulmonary congestion
ACE Inhibitor Drugs
- Anything ending in april
ex: Benzapril, Quinaprill
ACE Inhibitor Side Effects
DRY COUGH, hyperkalemia, renal insufficiency, hypotension from volume depletion
ACE Receptor Blockers
- Blocks angiotensin converting enzyme but NO bradykinin
- Use if cough from ACE Inh is prohibitive
- anything ending in artan
ex: Valsartan, Irbesartan
ACE Receptor Blocker Side Effects
Same as ACE Inh.
a2-adrenergic agonist mechanism
- Blocks sympathetic response from spinal cord to ganglia
- NOT FREQUENTLY USED
a2-adrenergic agonist drugs
Methyldopa
Clonidine
a2-adrenergic agonist side effects
dry mouth
sedation
-VERY COMMON EFFECTS LIMITING DRUG USE
a1-blocker mechanism
blocks a1 adrenergic receptors
a1-blocker drugs
Prazosin
Terazosin
Doxazosin
a1-blocker side effects
POSTURAL HYPOTENSION
increased in adverse outcomes vs thiazide
Hydralazine
- Opens up arteries
- Fall in pressure, but reflex increase in HR
- Must be given in tandem with drug to slow HR
- Rarely Used
Minoxidil
- Open up potassium channels, causing a decrease in pressure
- reflex HR increase
- used in people who fail standard treatment
Nitroprusside
- dilates arteries and veins
- rapid action and high potency
- reflex tachycardia
- only used in emergency situations
Don’t forget about B-Blockers and Ca+2 blockers
The best and most beautiful things in the world cannot be seen or even touched - they must be felt with the heart.
Helen Keller
Sildenafil
If your results last more than 3 awesome hours please call you doctor. Wait, that’s not right.
Sildenafil
- decreases vascular resistance
- mainly used in pulmonary hypertension
- SEVERE HYPOTENSION if used with NITRATES
Hypertension Beginning Treatment Plan
1) Control underlying condition and factors
2) Thiazide
Hypertension Treatment Plan with Cardiac Factors
Thiazide + B-blocker or ACE or mineralocorticoid
Hypertension Treatment Plan with Diabetic Factors
Thiazide + ACE or Ca+2 blocker
Hypertension Treatment Plan with Kidney Factors
Thiazide + ACE
