Antihypertensives B Flashcards
What are eight antihypertensive agents?
- Diuretics
- Central-acting Sympatholytics
- Peripheral-acting Sympatholytics
- Beta blockers
- ACE inhibitors
- Angiotensin II antagonists (ARBs)
- Calcium-channel blockers (CCBs)
- Direct vasoldilators
True or False:
Most diuretics are fairly inexpensive.
True
True or False:
Diuretics have a lower side effect profile than other antihypertensives.
False
(They have a higher side effect profile)
True or False:
Diuretics are often used in combination with other antihypertensives.
True
True or False:
When using diuretics, the higher the dose, the more it will lower blood pressure.
False
(BP lowering effects not necessarily dose related)
Which diuretic is most commonly used for blood pressure?
Thiazides
What is the MOA for thiazide diuretics?
- Inhibit Na+ and Chloride reabsorption at distal tubule
- Promotes Na+ and H2O loss
- Decreases blood volume
- Decreases preload
- Lowers BP
What is the thiazide prototype?
Hydrochlorothiazide
What is the route for Hydrochlorothiazide?
PO
What is the usual dose for Hydrochlorothiazide?
12.5 - 50 mg qd
What are three common indications for Hydrochlorothiazide?
- Htn
- Peripheral edema
- HF
How is Hydrochlorothiazide metabolized?
There is no metabolization
(excreted unchanged)
How is Hydrochlorothiazide excreted?
Renal
What are the four side / adverse effects of Hydrochlorothiazide?
- Hypokalemia
- Hypomagnesemia
- Hyperuricemia
- Hyperglycemia
- Hyper-pee-emia
What are six precautions for Hydrochlorothiazide?
- Volume depletion
- Electrolyte abnormalities
- Severe renal impairment
- Arrythmias
- History of gait
- Diabetes
True or False:
Hydrochlorothiazide is generally safe and well-tolerated.
True
What kind of drug is Dofetilide (Tikosyn)?
Dysrhythmic
When Hydrochlorothiazide interacts with Dofetilide (Tikosyn), what happens?
Prolonged QT / other arrythmias
What are the four central-acting sympatholytics?
- Guanfacine (Tenex)
- Clonidine (Catapres)
- Guanabenz (Wytensin)
- Methyldopa (Aldomet)
Which central-acting sympatholytic is the drug of choice for Htn in pregnancy?
Methyldopa (Aldomet)
What is the route for Guanfacine (Tenex)?
PO
(Central-Acting Sympatholytic)
What is the route for Clonidine (Catapres)?
PO
(Central-Acting Sympatholytic)
What is the route for Guanabenz (Wytensin)?
PO
(Central-Acting Sympatholytic)
What is the route for Methyldopa (Aldomet)?
PO
(Central-Acting Sympatholytic)
What is the MOA for central-acting sympatholytics?
- Stimulate alpha-2 receptors in the brain (agonist)
- Repeated stimulation of receptors shuts down release of NE to
- Heart
- Kidneys
- Peripheral Vascular
- Reduces total PVR ⇢ Lowered BP
What is the centrally-acting sympatholytic prototype?
Methyldopa (Aldomet)
What is the usual dosage for Methyldopa (Aldomet)?
250 - 500 mg bid
What are the two indications for Methyldopa (Aldomet)?
- Moderate to severe HTN
- Hypertensive states in PG
How is Methyldopa (Aldomet) metabolized?
Liver
How is Methyldopa (Aldomet) excreted?
Primarily renal (some feces)
What are the eight select adverse / side effects of Methyldopa (Aldomet)?
- Sedation
- Bradycardia
- HA
- GI upset
- Dry mouth
- Depression
- Orthostatic hypotension
- Rebound hypertension
True or False:
Rebound hypertension from sudden withdrawal from Methyldopa (Aldomet) may be higher than pre-treated blood pressure
True
What are the four significant drug interactions of Methyldopa (Aldomet)?
- MAOIs (Monoamine oxidase inhibitors)
- Oral Fe+
- In pregnant ladies, separate doses by 2 hours
- Caution with levodopa
- General anesthetics
What is Methyldopa (Aldomet) contraindicated to?
Active hepatic disease
What are the four peripheral-acting sympatholytics?
- Doxazosin (Cardura)
- Prazosin (Minipress)
- Terazosin (Hytrin)
- Reserpine (Serpasil)
What is the route for Doxazosin (Cardura)?
PO
(Peripheral-Acting Sympatholytic)
What is the route for Prazosin (Minipress)?
PO
(Peripheral-Acting Sympatholytics)
What is the route for Terazosin (Hytrin)?
PO
(Peripheral-Acting Sympatholytic)
What is the route for Reserpine (Serpasil)?
PO
(Peripheral-Acting Sympatholytic)
Which peripheral-acting sympatholytic is currently unavailable in the US but will probably be back soon?
Reserpine (Serpasil)
What are peripheral-acting sympatholytics also known as?
Alpha-1 Blockers
What is a possible side effect for peripheral-acting sympatholytics, especially on the first dose?
Orthostatic hypotension
Besides Htn, some peripheral-acting sympatholytics are also used for what?
Benign Prostatic Hyperplasia (BPH)
What is the MOA for peripheral sympatholytics?
- Block alpha-1 receptors in arterioles and veins
- Prevents NE from binding to receptors
- Decreases CO and / or PVR
- Lowers BP
How do alpha-1 blockers treat benign prostatic hyperplasia (BPH)?
- Blocks alpha-1 receptors found in smooth muscle lining of prostate gland bladder neck
- Relaxation of smooth muscle in prostate gland and bladder neck
- Improved urine flow and decreased BPH symptoms
What is the Alpha-1 blocker prototype?
Doxazosin (Cardura)
What is the route for Doxazosin (Cardura)?
PO
What is the usual dose for Doxazosin (Cardura)?
-
Htn:
- Initially 1 mg qd - may titrate up over several weeks
- Max 16 mg/day
-
BPH:
- 4-8 mg/d
- Max 8 mg/day
What are the two indications of Doxazosin (Cardura)?
- Htn
- BPH
How is Doxazosin (Cardura) metabolized?
Liver
How is Doxazosin (Cardura) excreted?
Primarily feces (some part renal)
What are the five adverse / side effects of Doxazosin (Cardura)?
- Syncope
- Orthostatic hypotension
- Arrythmias
- HA
- Priapism
What is / are the contraindication(s) for Doxazosin (Cardura)?
Prostate cancer
What is / are the precaution(s) for Doxazosin (Cardura)?
Impaired liver function
What are the four significant interactions of Doxazosin (Cardura)?
- Cimetadine (Tagamet)
- Verapamil (Calan)
- Sildenafil (Viagra)
- Tamsulosin (Flomax)
What are the four indications for calcium channel blockers (CCBs)?
- Htn
- Angina
- Dysrhythmias
- Headache prohlyaxis
Calcium channel bloackers have variable effects on what two things?
- HR
- AV node conduction
What are the eight dihydropyridine CCBs?
- Nifedipine (Procardia)
- Amlodipine (Norvasc)
- Felodipine (Plendil)
- Isradipine (DynaCirc)
- Nicardipine (Cardene)
- Nisoldipine (Sular)
- Clevidipine (Cleviprex)
- Nimodipine
What are the three dihydropyridine CCBs that have in angina indication?
- Nifedipine (Procardia)
- Amlodipine (Norvasc)
- Nicardipine (Cardene)
Which dihydropyridine CCB is not used for Htn but instead is used for subarachnoid hemorrhage?
Nimodipine
What is the route for Nifedipine (Procardia)?
PO
(Dihydropyridine CCB)
What is the route for Amlodipine (Norvasc)?
PO
(Dihydropyridine CCB)
What is the route for Felodipine (Plendil)?
PO
(Dihydropyridine CCB)
What is the route for Isradipine (DynaCirc)?
PO
(Dihydropyridine CCB)
What is the route for Nicardipine (Cardene)?
PO / IV
(Dihydropyridine CCB)
What is the route for Nisoldipine (Sular)?
PO
(Dihydropyridine CCB)
What is the route for Clevidipine (Cleviprex)?
IV
(Dihydropyridine CCB)
What is the route for Nimodipine?
PO
(Dihydropyridine CCB)
What are the two non-dihyrdropyridine CCBs?
- Verapamil (Calan)
- Diltiazem (Cardizem)
What are the two non-dihydrophyridine CCBs indicated for?
- Verapamil (Calan)
- Diltiazem (Cardizem)
Angina
What is the route for Verapamil (Calan)?
PO
(Non-Dihydropyridine CCB)
What is the route for Dilitiazem (Cardizem)?
PO / IV
(Non-Dihydropyridine CCB)
What is the MOA of CCBs?
- Inhibit Ca++ influx into vascular smooth muscle and cardiac myocytes
- Dilates peripheral arterioles (vasodilation)
- Dilates coronary arteries (increase oxygen supply to heart)
- Decreases cardiac contractility ( - Inotrope)
In addition to
- vasodilation
- increase oxygen supply to heart
- negative inotrope
what are two more effects of CCBs’ MOA?
What is the net effect on BP?
- Decreases SA node automaticity
- Decreases AV node conduction
Decreases PVR which lowers BP
Which drug is the least selective of the CCBs? What does this mean in terms of adverse / side effects?
Verapamil (Calan)
Verapamil (Calan) has significant action on what two things?
- Heart
- Vessels