3. Hypertension Flashcards
What are the actions of angiotensin-II?
Vasoconstriction
Stimulation of aldosterone which acts at distal renal tubule
Cardiac and vascular muscle cell growth
ADH release from posterior pituitary
What do ACE-i do?
Limit conversion of angiotensin-I o angiotensin-II by inhibiting circulating and tissue ACE
What does a reduction in angiotensin-II activity result in?
Vasodilation Reduction in aldosterone release Reduced AD release Reduced cell growth and proliferation All contributing to antihypertensive effects
What are the most common ACEi?
LisinoPRIL
RamiPRIL
What are some adverse affects to ACEi?
Hypotension Dry cough (bradykinin association) Hyperkalaemia (low aldosterone) Cause or worsen renal failure Angioedema
What are the contradictions of ACEi?
Renal artery stenosis AKD Pregnancy CKD Idiopathic angioedema
What are the important drug interactions with ACEi?
Hyperkalaemic drugs
NSAIDs
Other antihypertensive agents
What are the most common angiotensin-II and receptor antagonists (ARBs) prescribed?
CandeSARTAN
LoSARTAN
What are some adverse effects with ARBs?
Hypotension
Hyperkalaemia
Cause or worsen renal failure
What are the contraindications for ARBs?
Renal artery stenosis
AKD
Pregnancy
CKD
What are some important drug interactions with ARBs?
Hyperkalaemic drugs
NSAIDs
What are L-type calcium channels?
Allow inward Ca2+ flux into cells - voltage operated calcium channel
Expressed throughout the body, including vascular smooth muscle cells and cardiac myocytes plus SA and AV node
What is the role of calcium channel blockers?
Target calcium initiated smooth muscle contraction
What are the 2 main categories of calcium channel blockers?
Dihydropyridines
Non-dihydropyridines (phenylalkylamines and benzothiazepines)
What is the role of dihydropyridines?
Selective for peripheral vasculature
Little chronotropic or inotropic effects
What is the role of phenylalkylamines?
Depresses SAN and slows AV conduction, negative inotropy
When are CCBs usually given?
Primary choice antihypertensive in low renin patients
Gives some examples of dihydropyridines?
AmlodIPINE
NifedIPINE
NimodIPINE
What is nimodipine useful for?
Selectivity for cerebral vasculature so useful for ischaemic effects of subarachnoid haemorrhage
What are the adverse effects of dihydropyridine drugs?
Ankle swelling
Flushing
Headaches
Palpitations
What are the contraindications for dihydropyridine drugs?
Unstable angina
Severe aortic stenosis
What are some important drug interactions with dihydropyridine drugs?
Amlodipine + simvastatin (increased effect of statin)
Name the phenylalkylamines drug
Verapamil
What is phenylalkylamines used for?
Arrhythmia
Angina
Hypertension
What are the adverse effects of phenylalkylamines?
Constipation
Bradycardia
Heart block
Cardiac failure
What are the contraindications for phenylalkylamines?
Poor LV function
AV nodal conduction delay
What are the important drug interactions with phenylalkylamines?
Beta blockers
Other antihypertensive and antiarrhythmic agents
Name a benzothiazapine
Diltiazem
Name a thiazide diuretic
Bendroflumethiazide
Name a thiazide-like diuretic
Indapamide
What do thiazide and thiazide-like diuretics do?
Inhibit Na+/Cl- co-transporter in distal convoluted tubule
Decrease Na+ and H2O reabsorption
What are the adverse effects of thiazide and thiazide-like diuretics?
Hypokalaemia Hyponatraemia Hyperuricemia (gout) Arrhythmia Increased glucose Small increase in cholesterol and triglyceride
What are the contraindications for thiazide and thiazide-like diuretics?
Hypokalaemia
Hyponatraemia
Gout
What are the important drug interactions with thiazide and thiazide-like diuretics?
NSAIDs
Decrease K+ drugs such as loop diuretics
What drug is given in resistant hypertension?
Spironolactone - aldosterone receptor antagonist
What are the adverse effects of spironolactone?
Hyperkalaemia
Gynaecomastia
What are the contraindications of spironolactone?
Hyperkalaemia
Addison’s
What are the important drug interactions with spironolactone?
Increased K+ drugs
Pregnancy
What is the role of beta-adrenoceptor blockers?
Decrease sympathetic tone by blocking NA and reducing myocardial contraction resulting in reduced cardiac output
Decreased renin secretion
What are the adverse effects of beta-adrenoceptor blockers?
Bronchospasm Heart block Raynaud’s Lethargy Impotence Mask tachycardia
What are the contraindication for beta-adrenoceptor blockers?
Asthma
COPD
Haemodynamic instability
Hepatic failure
What are the important drug interactions with beta-adrenoceptor blockers?
Non-dihydropyridine CCBs verapamil and diltiazem
Name some beta-adrenoceptor blockers
LabetaLOL
BisoproLOL
MetoproLOL
Name a alpha-adrenoceptor blocker
DoxazOSIN
What is the role of alpha-adrenoceptor blockers?
Reduce peripheral vascular resistance
Selective antagonism of alpha-1 adrenoceptors
What are the adverse effects of alpha-adrenoceptor blockers?
Postural hypotension Dizziness Syncope Headache Fatigue
What are the contraindications for alpha-adrenoceptor blockers?
Postural hypotension
What are the important drug interactions with alpha-adrenoceptor blockers?
Dihydropyridine CCBs - oedema
