L 33-35 Flashcards Preview

Pharmacology Fall 2015 > L 33-35 > Flashcards

Flashcards in L 33-35 Deck (30):
1

4 Main categories of drugs used for hypertension

1) Diuretics
2) Drugs affecting SNS (sympatholytics): alpha-2 agonists, alpha-1 blockers, beta blockers
3) Vasodilators: NO, K+ channel, D-1 receptor, Ca channel
4) RAAS inhibitors: ACEI, ARB's (ang receptor blockers), Renin inhibitor

2

Anti-hypertension drugs in diuretics category

Hydrochlorothiazide (prototype)
Furosamide

3

Anti-hypertension drugs in sympatholytic category that are alpha-2 agonists

Clonidine
Methyldopa

4

Anti-hypertension drugs in sympatholytic category that are alpha-1 blockers

Prazosin
Doxazosin
Terazosin

5

Anti-hypertension drugs in in sympatholytic category that er beta-blockers

Propranolol, Timolol, Nadolol (non-specific)
Metoprolol, Atenolol, Nebivolol (beta-1 specific)
Acebutolol (beta-1, with ISA)
Pindolol (with ISA)
Carvedilol (alpha and beta blocker)

6

Anti-hypertension drugs in vasodilator category that act through NO

Hydralazine
Sodium nitroprusside

7

Anti-hypertension drugs in vasodilator category that open K+ channels

Minoxidil
Diazoxide

8

Anti-hypertension drugs in vasodilator category that stimulate D-1 receptors

Fenoldopam

9

Anti-hypertension drugs in vasodilator category that are Ca channel blockers

Verapamil
Diltiazem
Nifedipine

10

Anti-hypertension drugs in RAAS inhibitor category

Captopril (-pril's)–ACE inhibitors
Losartan (-sartan's)–ARB's=angiotensin receptor blockers
Aliskiren–Renin inhibitor

11

Specific causes of Hypertension

Renal artery constriction
Coarctation of aorta
Pheochromocytoma
Cushing's disease
Primary aldosteronism

12

Common complications of hypertension

CAD
Stroke
Renal failure

13

Sympathetic receptor that stimulates renin secretion

beta-1

14

4 ways SNS affects blood pressure

1) Resistance arterioles
2) Capacitance venules
3) Heart output
4) Renin secretion

All increase BP, this is why sympatholytics are used for HT

15

Explain Baroreceptor reflex

1) Baroreceptor in carotid sinus senses MAP
2) Signal sent to nucleus of tractus solitarius onto inhibitory neurons that fire into the vasomotor center
3) Vasomotor center sends signal down spine to autonomic ganglia
4) Autonomic Ganglia send motor fibers out to sympathetic nerve endings that act on alpha/beta receptors

Increased baroreceptor firing => inhibition of vasomotor center=> decreases SNS tone=> decreased BP

All happens within 3-4 beats

16

What should be done before initiating drug therapy for HT?

Life-style modification before drugs:
Exercise
Lose weight
Limit dietary salt, fat, alcohol
Stop smoking

17

Why must BP be dropped slowly, especially in elderly?

To prevent damage to vital organs.
In elderly, coronary perfusion may become inadequate=>morbidity and mortality

18

In patients over 50, which part of BP is more significant in terms of cardiac risk factor?

Systolic matters more than diastolic in persons over 50

19

What is initial drug treatment for all HT patients, and what is the most significant contraindication?

Thiazides are first line for most patients
Except for those with a sulfa allergy
Or those with high-risk conditions like: DM, kidney disease, ischemic heart dis., HF, cerebrovascular disease.

20

Thiazide mech of action to lower BP

Thiazides act in distal convoluted tubule to block Na/Cl co-transport.
Dec Na reabsorption=>decrease in blood volume and decrease in CO=>dec BP
Over time, dec Na in smooth muscle cells=>dec muscle sensitivity to vasopressors. Also with time cause K channel opening=>vasodilation

21

Indapamide

Thiazide type diuretic that also is a direct vasodilator

22

Common side-effects of thiazide diuretics used to reduce BP

Impotence
Gout–competes for transporter in kidney
Hypokalemia
Muscle cramps
Dec insulin production=> increased plasma lipids, reduced glucose tolerance

23

In what populations are Thiazides more effective?

African-American
Elderly

24

Name 2 main centrally acting Sympatholytics

Clonidine
Methyldopa

25

Mech of action for centrally acting Sympatholytic agents

Alpha-2 agonists in Medulla that reduce peripheral sympathetic activity=>vasodilation and reduced renin secretion

26

Differences in action between Clonidine and Methyldopa

Clonidine lowers HR and CO more than Methyldopa
Methyldopa is a prodrug that is converted to methylnorepinephrine

27

Mech for xerostomia with sympatholytics

Activation of alpha-2 receptors blocks function of most preganglionic nerves throughout the body, high doses will inhibit cholinergic activation of PSNS to salivary glands

28

Sudden withdrawal of Clonidine will cause:

Hypertensive crisis because of down regulation of alpha-2 receptors

29

Side effects of Methyldopa

Hemolytic anemia with pos Coombs test
Gynecomastia and lactation

30

Most common side-effects of sympatholytics

Sedation
Nausea, dizziness, nightmares, depression