2 Antihypertensive Drugs Flashcards
What is the mechanism of action for antihypertensive drugs?
- Increase the formation and exertion of urine
* Increase the renal excretion of water and sodium, decreasing the volume of fluid within the vascular system
What are the classifications of diuretics?
Thiazide diuretics
Loop diuretics
Potassium- sparing diuretics
What are thiazide diuretics?
act primarily on the
early portion of the distal tubule of the nephron, inhibiting sodium reabsorption, most frequently used drugs for HTN
What are loop diuretics?
act on the ascending limb
of the loop of Henle, inhibit the reabsorption
of sodium and chloride from the nephron
What are potassium- sparing diuretics?
prevent the secretion of potassium into the distal tubule, and sodium is excreted
What are the adverse effects of diuretics
- Fluid depletion
- Electrolyte imbalance
- Sodium depletion (hyponatremia)
- Potassium depletion (hypokalemia)
- Reflex increase in cardiac output
- Increase in peripheral vascular resistance
- Impaired glucose and lipid metabolism
- GI disturbance
- Weakness-fatigue
- Orthostatic hypotension
In the context of antiHTN, what is the mechanism of action of beta blockers?
– Decrease HR and force myocardial contraction
– Slows HR and reduces cardiac output
– Decrease in sympathetic tone
What is an example of a sympatholytic drug?
Beta blocker
In the context of antiHTN drugs, what are the side effects of beta blockers?
• Nonselective beta blockers( beta -1 and beta – 2 receptors) produce bronchoconstriction in pts with respiratory disorders • Depression of HR • Decreased myocardial contractility • Orthostatic hypotension • Depression • Fatigue • GI disturbance • Allergic reactions
What are the side effects of alpha blockers?
- Reflex tachycardia
- increase HR
- Orthostatic hypotension
- Increase risk of cardiac disease
- CHF
What are the mechanisms of action of ganglionic blockers?
- Decreases systemic sympathetic activity
- Block transmission at the junction between presynaptic and postsynaptic neurons in sympathetic and parasympathetic pathways
- Used sparingly because of the effect on both divisions of the ANS
- Used with acute aortic dissection and SCI
What are the adverse effects of ganglionic blockers?
- Nausea and constipation
- Urinary retention
- Visual disturbance
- Orthostatic hypotension
What is the mechanism of action of vasodilators?
- decrease peripheral vascular resistance
- inhibit smooth muscle contraction
What are the side effects of vasodilators?
- reflex tachycardia
- increased HR
- dizziness
- postural hypotension
- weakness
- nausea
- fluid retention
- headache
- increase hair growth on face, ears, forehead
In the context of antiHTN, what is the mechanism of action of calcium channel blockers?
- Block calcium inhibiting contraction
- Vasodilation
- Decreased vascular resistance
- Decrease myocardial contraction force
