CVS part 1 hypertension & diuretics Flashcards
What 3 things does NA affect to control BP?
- Alpha 1 receptors on venules & arterioles - vasoconstriction
- Beta 1 receptors on the heart - increase CO
- Beta 1 receptors on kidneys - increase renin secretion, activates RAAS
What 2 effects does angiotensin 2 have?
It acts on angiotensin 1 in the arterioles - causing vasoconstriction
It causes aldosterone secretion - increased salt & H2O retention in kidneys
In what 5 ways can we target high BP?
- decrease blood volume
- decrease vasoconstriction
- decrease heart rate
- decrease sympathetic outflow
- decrease angiotensin effects
What is secondary hypertension?
Hypertension caused by a specific pathology in the body. Eg. Kidney failure
What are 4 complications of hypertension?
- Left ventricular hypertrophy
- CVA
- Ischemic heart disease
- Heart failure
what types of medications can be used to treat angina?
- Beta-blockers OR
- Long-acting calcium channel blocker
what types of medications can be used for prior myocardial infarction?
Beta-blocker &
ACE-inhibitor
What medications can be used for heart failure?
ACE-inhibitor &
Carvedilol OR
Spironolactone
-if significant volume overload: loop diuretic used
What medication is used for left-ventricular hypertrophy?
ACE-inhibitor
What medication is used for secondary stroke prevention?
Hydrochlorothiazide &
ACE-inhibitor
what type of medication is used for diabetes type 1 & 2?
ACE-inhibitor, usually with diuretic
what medication type is used for chronic kidney disease?
ACE-inhibitor, usually with diuretic
What medication is used for systolic hypertension?
Hydrochlorothiazide OR
Long-acting calcium channel blocker
What medication is used for hypertension in pregnancy?
Methyldopa
what is methyl-dopa’s MOA?
It’s a prodrug. Converted to methyl NA in the CNS. Stimulation of central alpha-adrenoreceptors. Increased stimulation leads to decreased sympathomimetic output (less NA released)
what is the half-life & dosage of methyl dopa?
2 hrs
Dosage: 250mg bi-daily. Max 3g/d
what is the clinical use of methyl dopa?
hypertension in pregnancy
what are the side effects of methyl dopa?
Sedation
Haemolytic anemia
what are interactions with methyl dopa?
Parkinson’s disease
Geriatrics (fall risk)
Depression
what is the MOA of Clonidine(off-label)? & Moxonidine?
Direct stimulation of alpha-adrenoreceptors
what is the half life & dosage of Moxonidine & Clonidine?
2-3h
Moxonidine dosage: 0.2-0.4mg/d
Clonidine: 25 micrograms bi-daily (opioid withdrawal/menopausal flushes)
what are Moxonidine & Clonidine used for?
Mild to moderate hypertension
What are side effects of Moxodine & Clonidine?
Dry mouth, sleep disturbances, sedation, dizziness
what are interactions of Moxodine & Clonidine?
CNS depressants (eg. alcohol)
Geriatrics, glaucoma, epilepsy
Depression
What is the MOA of Doxazosin & terazosin
Alpha-1 antagonist, prevents NA from binding leading to reduced vasoconstriction
What is the time of onset and half-life for Doxazosin & terazosin?
Onset: 1-2h
Half-life: 19-22h
what is the dosage for Doxazosin & terazosin?
Hypertension: 4-8mg controlled release
BPH(benign prostate hyperplasia): 1-4mg/d at night
what is Doxazosin & terazosin used to treat?
Hypertension, BPH, phaeochromocytoma hypertension
What are side effects of Doxazosin & terazosin?
Hypotension (1st dose), vertigo, dizziness, palpitations, tachycardia, peripheral oedema, nervousness, somnelence
What are the interactions of Doxazosin & terazosin?
GIT & oesophagal obstructions
Never used as monotherapy
what is the MOA of hydralazine?
Induces arteriolar vasodilation by preventing oxidation of NO (nitric oxide) & therefore lowering BP
what is the half life & dosage of Hydralazine?
2-4h
20-25mg bi-daily
what are the 3 uses of Hydralazine?
Hypertension, BPH, phaeochromocytoma hypertension
what are the side effects of hydralazine?
Hypotension (1st dose); reflex tachycardia, headache, lupus-like syndrome, fluid retention
what are the interactions of hydralazine? (lots that’s why it’s a 4th line drug)
Aortic stenosis
Hypertrophic obstructive cardio myopathy
Tachycardia
Lupus
Other anti-hypertensives
What is the MOA of nitroprusside?
Direct, causes vasodilation via release of NO
what is the clinical use of nitroprusside?
Hypertensive emergencies
what is the half-life & dosage of nitroprusside?
1-10min
0.3-1.5 micrograms/kg/min
what is the side-effect of nitroprusside?
Severe hypotension
what are the interactions with nitroprusside?
Tachycardia
Other anti-hypertensives
what is Diazoxide used for?
Hypertensive emergencies
Hypoglycemia
what is the MOA of Diazoxide?
Activates potassium channels, causing arteriolar dilation
Side effects of Diazoxide?
Hyperglycemia, hypotension, sodium & water retention
How do Dihydropyridines work?
Block calcium channels, calcium can’t enter muscle cells, causing vasodilation & decreased BP
Amlodipine, Felodipine, Lercanidipine, Nifedipine, Nimodipine are all examples of what type of drug?
Calcium channel blockers
what are indications for Amlodipine?
Hypertension, angina, Raynaud’s syndrome
what are the side effects of Amlodipine?
Peripheral oedema, dizziness, headache, flushing & hypotension
what is the onset time & dosage of Amlodipine?
6-12hrs (long-acting)
2.5-10mg/d (single dose)
what are the interactions of Amlodipine?
CYP3A4 inhibitors increase levels (eg. grapefruit)
Simvasatin (not above 20mg/d) will cause
oedema, fatigue, constipation.
Other anti-hypertensives
What are indications for Felodipine?
Hypertension & angina
what are the side effects of Felodipine?
Headache, dizziness, flushing, peripheral oedema
what is the onset time & dosage of Felodipine?
Onset time: 2-5hrs
5-20mg/d (single dose)
what are the interactions with Felodipine?
similar to Amlodipine, avoid grape juice
what is the indication for Lercanidipine?
Hypertension
What are the side effects of Lercanidipine?
Peripheral oedema, headache, dizziness, flushing
what is the onset time & dosage for Lercanidipine?
1.5-3hrs
10-20mg/day (single dose)
what are the interactions with Lercanidipine?
Strong CYP3 metabolism - avoid grapefruit juice & strong inhibitors (ketoconazole & clarithromycin)
what are indications for Nifedipine?
Hypertension, angina, Raynaud’s syndrome
what are side effects of Nifedipine?
Reflex tachycardia, oedema, flushing, gingival hyperplasia- gums become thicker
what is the onset time & dosage of Nifedipine?
30-60min (IR), 6hrs (ER)
30-90mg/d (ER formulation)
what are the interactions with Nifedipine?
Avoid immediate-release formulation for chronic hypertension
CYP3A4 metabolism
what are the indications for Nimodipine?
Nimo= Nemo = special
Subarachnoid hemorrhage (prevention of vasospasm)
what are the side effects for Nimodipine?
Hypotension, headache, nausea, flushing
what is the onset time & dosage for Nimodipine?
1 hour
60mg every 4hrs for 21 days (oral)
what is the interactions for nimodipine?
Avoid IV use (risk of severe hypotension)
Strong CYP3A4 interactions
what are the effects of beta-1 receptors on the heart?
Positive ionotropic & chronotropic effects, increase automaticity
which 3 drugs are non-selective beta-blocking agents?
Propranolol, Sotalol, Timolol
which drugs are beta-1 selective?
Atenolol, Bisoprolol, Metoprolol, Nebivolol
which drug is a vasodilatory non-beta-1 selective?
Carvedilol
