Drugs Week 6-11 Flashcards
Which drug categories are considered ANTIHYPERTENSIVES? (7)(8)
- Diuretics
- Calcium Channel Blockers
- Beta Blockers
- ACEi Inhibitors
- ARB
- (Direct Renin Inhibitor)
- Central Acting Alpha Agonist
- Nitrates
What are diuretics used for?
-Limit water and sodium reabsorption, this causes increased excretion of NA+ and water by kidneys.
What is the recommended initial therapy for all HTN patients?
Diuretics
What are the three main classifications of diuretics?
Short explanation of each.
Loop diuretics:
- acts on ascending limb of loop of Henle - inhibits reabsorption of Na/K/2CL, thus preventing reabsorption of water that follows
Thiazide diuretics:
- acts on the early part of the distal convoluted tubes - inhibits mechanisms that favor Na+ reabsorption, resulting in Na and K excretion and reabsorption of Ca+
- Potassium-sparing diuretics
- acts on the late part of the distal convoluted tubes
- inhibits the sodium potassium pump, thus limiting the reabsorption of Na+ and excretion of K+
What is the biggest AE in all diuretics?
Dehydration
What are the other AE besides dehydration associated with Loop Diuretics?
- hypokalemia (K+)
- hyponatremia (Na+)
- hypocalcemia (Ca+)
- ototoxicity (ear)
- hyperglycemia
What is an example of a Loop Diuretic?
furosemide (Lasix)
What are the AE associated with Thiazide Diuretics?
- Same as loop diuretics except:
- hypercalcemia
- significant loss of K+
What is an example of a Thiazide Diuretic?
hydrochlorothiazide (HCTZ)
Why are Thiazide Diuretics helpful for older adults?
Thiazide diuretics reabsorb calcium unlike loop diureteics. This helps maintain bone density and prevent kidney stones.
What is the biggest AE associated with Potassium Sparing Diuretics?
Hyperkalemia
What is an example of a Potassium Sparing Diuretic?
What is different about this drug?
- spiranolactone
- It blocks aldosterone receptors which can produce:
- gynecomastia in males
- menstrual irregularities in females
Which diuretic is the most common?
Which diuretic is less effective in producing diuresis?
- Thiazide
- Potassium Sparing
All diuretics reduce plasma volume. What does this cause?
-hyperglycemia
What drugs counteract diuretics?
NSAIDs (Na+ retention)
What are calcium channel blockers used for?
Block Ca2+ entrance into vascular smooth muscles, thus disallowing excitability, which in return causes vasodilation.
What are the AE assoiated with all calcium channel blockers?
- HA
- dizziness
- hypotension
- bradycardia
- reflex tachycardia
What are the three classes of Ca+ Channel Blockers?
What do they each act on?
Dihydropyridines:
-reduce arteriolar tone
Phenylalkyamines:
-affect the heart
Benzothiazepines:
-affect heart and vasculature
When are Ca+ Channel Blockers useful?
When Beta Blockers are contraindicated.
What is an example of a dihydropyridine?
amlodipine
What is an example of a benzothiazepine?
diltiazem
How do Beta Blockers work?
What does this result in?
Block the effect of (nor)epinephrine. Act as a competitive antagonist of Beta adrenoceptors
Results in negative inotropic effect (SV)
Results in negative chronotropic effet (HR)
What does it mean when a Beta Blocker is nonselective?
It blocks both B1 and B2 adrenoceptors.
If it were selective it would only block B1.
Ultimately, Beta Blockers job is to reduce _________ influences. This in return means a reduce in what?
Sympathetic
Workload of the heart
What is an example of a NONSELECTIVE Beta Blocker drug?
-propranalol
What are the 2 cardioSELECTIVE (B1) Beta Blockers?
- metropolol
- carvedilol
When a patient is on a Beta Blocker, should we monitor exercise tolerance by HR?
No, must use a different rate
What do Beta Blockers usually end in?
“-lol”
How do ACEi drugs work?
They block the conversion of angiotensin I to angiotensin II
angiotensin II acts to constrict blood vessels, ACEi drugs inhibit this
What do ACEi drugs usually end with?
“-pril”
What are the AE associated with ACEi drugs?
Common
- Dry cough
- Hypotension
- Hyperkalemia
Rare, serious AE:
- Acute renal failure
- Angioedema
What patients would be on an ACEi drug for an extended amount of time?
Stroke victims
What are some examples of ACEi drugs?
- lisinopril
- enalapril
- ramipril
How do ARBs work?
Blocks the binding of angiotensin II at AT1 receptor
What are the AE of ARBs?
Same as ACEi but without the dry cough
What do ARBs end in?
“-sartan”
When are ARBs used?
When ACEi intolerant, or when a cough is developed while on ACEi
What are some examples of ARBs?
- losartan
- valsartan
What type of drug is the best tolerated of all HTN medications?
ARBs
What is considered the triply whammy?
ACEi, Diuretic, NSAID
How do Direct Renin Inhibitors work?
Block conversion of angiotensinogen to angiotensin I
What are the AE of Direct Renin Inhibitors?
Similar to ACEi/ARB
Should we take RAAS inhibitors in combination with other drugs?
No, due to increased AE
How do Central-Acting Alpha Agonists work?
Directly act on the CNS presynaptic neurons to cause a negative feedback loop resulting in less norepinephrine production.
What are the AE of Central-Acting Alpha Agonists?
- Dizziness
- Drowsiness
- Fatigue
- HA
What is an example of a Central-Acting Alpha Agonist drug?
What is it reserved for?
AE?
Route?
clonidine
- reserved for resistant HTN
- dry mouth, rash with patch
- PO or weekly patch
How do Nitrates work?
- Work directly on smooth muscle instead of a receptor (MOA unknown)
- Appears to decrease preload and afterload which in return reduces the workload of the heart
What are the forms of nitrate?
Which are long acting and which are short acting?
Long acting:
- oral
- transdermal
Short acting:
- sublingual
- chewable tablet
- IV
What are some examples of nitrates?
- nitroglycerin
- isosorbide mononitrate
What is different about ISMN (isosorbide mononitrate) and ISDN (isosorbide dinitrate)?
ISDN undergoes significant first-pass metabolism and has a half-life of 1 hour.
ISMN has a half-life of 4-6 hours
What is unique about the storage of nitrates?
- Limited light exposure (kept in brown bottle)
- Short shelf life (6m unopened, 3m opened)
- Tingling sensation as drug dissolves= active drug
Dosing of nitrates:
- After 1st dose, relief should occur in ____.
- 2nd dose if symptoms are still present after ___ (up to _ doses in __ minutes)
-1-2 minutes
5 minutes/ 3 doses in 15 minutes
What is possible if no relief occurs?
Possible MI