Hypertension Drugs Flashcards by Maya Noiles

Name some of the risks assosiated with hypertension…

Increased Stroke Risk
Increased Risk of Ischemic heart disease (angina, MI)
Other cardiovascular problems

morbidity/mortality

How well did you know this?

Not at all

Perfectly

What level of blood pressure is considered high enough to treat?

Sustained Systolic about 160mm
Sustained Diastolic above 100mm

But if know cardiovascular disease:
sustained systolic 140-159 mm Hg and/or
diastolic BP 90-99 mm Hg

How well did you know this?

Not at all

Perfectly

What things do you need to reduce in order to treat blood pressure?

Reduce cardiac output by reducing:
heart rate stroke volume plasma volume

Reduce total peripheral resistance by dilating arterioles

How well did you know this?

Not at all

Perfectly

Name some antihypertensives and their basic mode of action

Diuretics- Reduce plasma volume then gradually TPR

vasodilators- Directly lower TPR

b-blockers- Reduce cardiac output & kidney renin secretion

ACE inhibitors- Inhibit endogenous vasoconstrictor production

a-blockers - Reduce TPR by inhibiting noradrenaline action

angiotensin antag -Reduce TPR by inhibiting angiotensin action

How well did you know this?

Not at all

Perfectly

Where do diuretics act?

And what is there action?

They act on the kidney to increase urine output.

They method of action is to:
Increase Na+ excretion
reduce salt re-absorption from glomerular filtrate 
water loss follows 
reduce plasma volume
reduce cardiac output

How well did you know this?

Not at all

Perfectly

Name some types of diuretics…

Thiazides
Loop diuretics
Potassium Sparing Diuretics

How well did you know this?

Not at all

Perfectly

What is the most POTENT type of diuretic?

Loop Diuretics

They can make you go ‘loopy’ they’re so strong

How well did you know this?

Not at all

Perfectly

What’s the most widley used diuretic?

Thiazide Diuretics.

ie
– chlorothiazide
– hydrochlorothiazide
– bendrofluazide

How well did you know this?

Not at all

Perfectly

Where is the sight of action for Thiazide Diuretics?

The Distal Tubule

They inhibit Na and Cl co-transport in the distal tubule. Also have vasodilation properties which have an unknown mechanism.

How well did you know this?

Not at all

Perfectly

True or false:

Thiazides Increase Renin release.

True
Thiazide diuretics do increase renin release.
Which may conteract BP as it can increase BP.

How well did you know this?

Not at all

Perfectly

What potency are Thiazide Diuretics?

They are moderate potency, so suitable for most patients.

How well did you know this?

Not at all

Perfectly

Name some Thiazides:

Derived from Benzothiadiazine:

And Thiazide like structures:

Derived from bensothiadiazine:
– chlorothiazide
– hydrochlorothiazide
– bendrofluazide

Thiazide Like structures:

Chlorthalidone
metolazone

How well did you know this?

Not at all

Perfectly

Name some Thiazide Side effects…

More frequent urination
Hypokalemia
Diuretic properties reduce over time but vasodilation propeties remain

How well did you know this?

Not at all

Perfectly

In what situation would you give loop diuretics over thiazides

If an emergency
Patients with renal insufficiency
Patients with resistant hypertension or heart failure

How well did you know this?

Not at all

Perfectly

True or false:

Loop diuretics are more effective at lowering BP than thiazides

FALSE

Loop diuretics are no more effective than thiazides at reducing BP

How well did you know this?

Not at all

Perfectly

Name some Vasodilator Drugs in the treatment of BP

Calcuim Antagonists (Calcium Channel Blockers) MAIN ONE
Alfa-blockers

Special Circumstances:

Angiotensin Agonists
Potassium Channel Activators
Sodium Notroprusside
Hydralazine

How well did you know this?

Not at all

Perfectly

What is the sight for vasodilator action?

And how do they work?

The sight of action is the Smooth Muscle Cells surrounding the artery.

Action:
Lower intracellular calcium concentration. Cause muscle cell relaxation= vasodilation

How do Calcium Antagonists work?

They block Calcium from entering voltage operated calcium channels in arterial smooth muscle cells.

What categories are there within Calcium Channel Blockers (Calcium Antagonist)? And Name some…

Dihydrophyridines:

Nifedipine
amlodipine
nicardipine

Benzothiazepine
-Diltiazem

Which Calcium Antagonist also blocks calcium channels in conducting tissue of the Heart?

Benzothiazepine
(Diltiazem)

Which can slow the heart down and also potentiate Beta Blocker action

Which Calcium Antagonise is a once daily dose?

Amlodipine

As it’s longer acting

What are some advers effects of Calcium Channel Blockers (Calcium Antagonists)

All:

Flushing (due to dilation of facial vessles)
Ankle Oedema

Diltiazem

Cardiac Depression
Interaction with Beta Blockers

What is the mechanism of action of Diltiazem?

Blocks voltage-operated calcium channels in cardiac muscle

Oedema (swollen ankles) is a common side-effect of which of the following classes of anti-hypertensive drug?

Calcium channel blockers

True or false... Alfa 2 receptors are in the Smooth muscle and are a target for Antihyperintensives...

FALSE!!! Alfa 2 receptors are in nerve endings. Alfa1 receptors are targets for BP lowering drugs as they are in smooth muscle cells

What are the targets and mode of action for Alfa 1 blocker antihyperintensives?

They act on G proteins within the smooth muscle cells. They are selective blockers for alfa 1 adrenoceptors Prevent Vasoconstrictor action of endogenous noradrenaline

Examples of Alfa Blockers | hint SIN

Doxazosin 1xdaily Terazosin 1xdaily Prazosin 3xdaily

Name some SE of Alfa Blockers

-Postural Hypotension (dizzyness/lightheaded) -Possible severe lowBP after first dose but generally well tolerated

Name some Beta Blockers

Atenolol | Metoprolol

True or False: Beta Blockers bind to B1 adrenoceptors in the heart?

TRUE- they bind to sino atrial node + Ventricular muscle in the heart. **B2 receptors are for the airways**

How do B1 Blockers Treat high BP?

They block action of Noradrenaline release from the sympathetic Nerves and circulating adrenaline. Do this by binding and blocking B1 adrenoceptors in the heart.

Inital and long term affects of BBlockers....

Initial: reduces rate&force of heart beat. After Continued Treatment: Cardiac output returns to normal but BP remains low. (Total Periferal resistance resets at lower level)

SE of BBlockers

- Cold Hands - Fatigue & Difficulty excercisng Less common - can provoke asthma attack - heart failure - conduction block in heart - Could affect blood lipids

TRUE or FALSE Can BB provoke asthma attacks ?

Yes, but only if the patient is asthmatic to begin with

Name some ACE Inhibitors

Catopril 2xdaily Enalapril 1xdaily Lisinopril (lysine analogue of enalapril) Ramipril

Action of ACE Inhibitors

-prevent Conversion of Angiotensin 1 -> Angiotensin 11 (which is a potent vasoconstrictor and inhibits H20 excretion) -Causes Vasodilation -Reduces Plasma volume

Name some effects of Angiotensin 11 (the thing that ACE inhibitors block)

Angiotensin 11 is a potent vasoconstrictor and it also stimulates aldosterone secretion (which inhibits salt and H20 excretion)

Some SE of ACE Inhibitors

- Dry Cough - Hypotension initially, especially if given with diuretic These effects wear off with time

Losartan is often preferred to enalapril in the treatment of hypertension because it...

Because it ... does not cause a dry cough Like ACE Inhibitors do!

Name some Angiotensin 11 receptor antagonists | Tan

Losartan Candesartan Eprosartan Valsartan

What do Angiotensin 11 antagonists do?

Block Action of Angiotensin 11 at it's receptors, therefore blocking the effects of it (Vasoconstriction + Aldosterone secrion)

When are Angiotensin 11 receptor antagonists used?

- They're used in combo with ACE inhibitors as they improve the mortality and morbidity compared to ACE inhibitors alone - They provide an alternative to ACE inhibitors when patients are intolerant (or have SE ie dry cough)