Hypertension and Anti-Hypertensive Drug Pharmacology Flashcards
What is stage 1 hypertension?
140/90
ABPM - 135/85
What is stage 2 hypertension?
160/100
ABPM - 150/95
What is severe hypertension?
When either
S is >180
D is >110
What would you look for in a history to assess the risk of hypertension in the patient?
Smoking
Family history
Diabetic
Hypercholesterolaemia
What would you look for in the examination?
Assess if there is end organ damage
How would you look for LVH?
ECG and echocardiograms
How would you look for renal failure?
Renal ultrasounds
Estimated GFRs
Proteinuria (urine tests)
What is the step 1 treatment for a <55?
ACEI/ARBs
What is the step 1 treatment for >55s OR Afro-Caribbean OR of child bearing age?
CCBs
Step 2?
Add thiazide type diuretic
Step 3?
Add all three in
Step 4 if blood K+ is UNDER 4.5mmol/l?
Low dose SPIRONOLACTONE - 25mg/once daily. Can cause hyperkalaemia so careful in patients with a reduced GFR
Step 4 if blood K+ is OVER 4.5mmol/l
Use a higher dose thiazide type diuretic
Step 5?
Add a beta blocker
Step 6?
Use a “less common agent”
What is ramipril or perindopril and how do they work?
ACEIs - work by inhibiting ACE converting Angiotensin I to Angiotensin II
What does Angiotensin II do?
Makes aldesterone which retains Na+ therefore retaining fluid and increasing BP
Is also a vasoconstricor also increasing BP
What else can Angiotensin II do regarding organs?
Causes end organ damage - example is LVH as A2 is a hypertrophic agent
What is Conns and why does it produce HT as a symptom?
Excess aldesterone is made - increases BP
Contraindications of ACEIs?
Renal artery stenosis
Renal failure
Hyperkalaemia
Adverse drug reactions of ACEIs?
Cough main one
1st dose HYPOtension a risk
Renal impairment
Drug-drug interactions of ACEIs?
NSAIDS - precipitate acture renal failure
K+ supplements or K+ sparing diuretics - spironolactone
Why is using ACEIs when hyperkalaemic bad?
Aldesterone used to remove K+ - if already got too much and you inhibit this removal response messes things up
Name some ARBs
Losartan
Valsartan
Candesartan
Irbesartan
(SARTAN)
What receptor does ARBs block?
AT1
Do ARBS produce a cough?
No
What 2 types of CCBs we got?
Vasodilators and Rate limiting
Name the rate limiting CCBs.
Verapamil or diltiazem
How do the rate limiting CCBs limit the rate?
Block the L type channels - negative inotropic effect
Also relax arteries which reduces TPR and CO - reduced myocardial O2 demand
Name some vasodilating CCBs
Amlodipine and Felodipine
When are vasodilating CCBs used?
In over 55s or women of child bearing age
CCBS contraindications?
Rapid vasodilators can precipitate stroke or MI so NEVER use in at risk patients
Adverse drug reactions of all CCBs?
Flushing
Headache
Ankle Oedema
Adverse drug reactions of Rate limiting?
Bradycardia and Constipation
Name some thiazide type diuretics?
Indapemide
How to thiazides Ds work?
Block Na+ reabsorption (antinaurtic) and cause you to pee
How long can thiazides take to show antiHT effects?
Weeks
Adverse effects of thiazide Ds?
Gout
Impotence
These not common
What are the “less commonly used” agents?
Alpha-1-adrenoreceptor antagonists
Centrally acting agents
Vasodilators
Name a A1-adrenoreceptor antagonist.
Doxazosin
How does doxazosin work?
Blocks the receptor and opposes smooth muscle contraction in arteries
Adverse drug reactions of doxazosin?
1st dose HYPOtension
Dizziness
Headache
Dry mouth
When should doxazosin be used?
Young patients who cannot tolerate other drugs
Name a centrally acting agent, how does this drug work?
Methyldopa - alpha-2 receptor agonist causing vasodilation
When is methyldopa used?
HT in pregnancy
Adverse drug reactions of methyldopa?
Sedation
Dry mouth
Postural hypotension
What is postural hypotension?
Rapid fall of BP when you stand up
Name 2 vasodilators?
Hydralazine
Minioxidil
