Hypertension Flashcards
Give some examples of ACEi:
-ramipril
-lisinopril
Limit conversion of angiotensin 1 to angiotensin 2
-reduced angiotensin 2 means vasodilation, reduced aldosterone release, reduced ADH release and less cell proliferation and growth
Function of angiotensin 2:
- vasoconstriction
- increase ADH release from posterior pituitary
- increased aldosterone release from adrenal cortex (zone glomerulosa) which acts on distal tubule
- increased cardiac and vascular cell proliferation and growth
What is Ag2 also produced by?
Chymases regardless of ACE
Adverse effects for ACEi
- hypotension
- dry cough (due to bradykinin potentiation)
- hyperkalaemia
- cause or worsen renal failure
- angioedema
Contraindications for ACEi
- renal artery stenosis
- aki/ckd
- pregnancy
- idiopathic angioedema
Drug interactions for ACEi
- drugs that increase K+
- NSAIDs (as these stop prostaglandin synthesis which are powerful vasodilators)
- other antihypertensive agents
Examples of ARBs
Candesartan and Losartan
-directly target AT1 receptors, more effective at inhibiting Ag11 mediated vasoconstriction than ACEi due to chymases
Adverse effects of ARBs
- hypotension
- hyperkalaemia
- cause/worsen renal failure
Contraindications for ARBs
- renal artery stenosis
- pregnancy
- aki/ckd
Drug interactions for ARBs
- K+ increasing drugs
- NSAIDs
Action of CCBs
Target calcium initiated smooth muscle contraction (LTCC expressed in vascular smooth muscle and cardiac myocytes)
3 classes of CCBs
-1st choice antihypertensive in low renin patients
Act on different sites of the alpha1 subunit of LTCC
- dihydropyridines: act on peripheral vasculature, no chronotropic/inotropic effects
- non-dihydropyridines: phenylalkylamines and benzothiazipines
Examples of dihydropyridines
-amlodipine (long half life), nifedipine, nimodipine (selectivity for cerebral vasculature-usueful for ischaemic effects of subarachnoid haemorrhage)
Adverse effects of dihydropyridines
- ankle swelling
- flushing
- headaches
- palpitations (compensatory tachycardia due to low BP)
Drug interactions of dihydropyridines
amlodipine with simvastatin- increases effect of statin
Contraindications of dihydropyridines
- unstable angina
- severe aortic stenosis
Example of phenylakylamines
Verapamil
-class 4 anti-arhythmic agent
–ve chronotropic and ionotropic effect
Used for arrythmias/angina/hypertension
Adverse effects of phenylakylamines
- constipation
- bradycardia
- heart block
- cardiac failure
Contraindications of phenylakylamines
- poor LV function
- Av nodal conduction delay
Drug interactions of phenylakylamines
- B blockers
- other anti-hypertensives/antiarrythmic agents
Example of benzothiazepine
Diltiazem
