Vasodilators Flashcards
LB: Inhibition of L-type calcium channels causes
Decreased HR (lower SA firing)
AV velocity block
Decreased contractility of cardiovascular muscles
LB: Rank the effectiveness of the three calcium channel blockers on L-type calcium channels
Verapamil>Diltiazem>Amlodipine
LB: On what two phases of the cardiomyosite cycle do the calcium channel blockers have their effects
Phase 0 (decreases SA firing rate) Phase 2 (Plateau, reduces Myocyte contractility)
LB: ***What are the side effects of calcium channel blockers, and which drug has a higher incidence of each?
Hypotension - Amlodopine CHF - Verapamil AV Block - Verapamil Edema - Amlodopine Constipation - Amlodopine Headaches - Verapamil
LB: What is the most commonly used K-channel opener and what does it target?
Minoxidil - Very potent arterial vasodilator, results in compensatory increase in HR and cardiac output, as well as fluid retention.
LB: What is an interesting alternative use of minoxidil?
It can be used to treat male pattern baldness because a side effect is hypertrichosis (Rogaine)
LB: Guanylyl Cyclase activators have what mechanism of action?
Increase production of cGMP, which results in ***equal venodilation and arteriodilation.
LB: What is the net effect of guanylyl cyclase activators?
Decrease of TPR and Cardiac Output, causing a decrease in BP and compensatory increase in HR
LB: Which guanylyl cyclase activator class can not be given P.O.?
Nitroprussides
LB: What type of calcium channel blocker has the largest vasodilator effect, and what type of vessel does this have the most effect?
DHPs (like Amlodipine) - Arteriodilation
LB: Organic nitrates effect both types of blood vessels. What types of blood vessels are dilated in low and in high doses?
Low doses will cause venodilation, high doses will add arteriodilation effects as well. HR increases as compensation in both cases.
LB: Aside from hypotension, what is an important factor to keep in mind when prescribing organic nitrates?
Patients can develop a tolerance - only use it for certain parts of the day (patch on during day, patch off at night)
LB: What route is Nitric Oxide given?
Inhalational, results in very low half life (3-6 seconds)
LB: The guanylyl cyclase activator hydralazine has a unique side effect:
ANA: A lupus like syndrome that is reversible on cessation of the medicine. More common at higher doses and in slow acetylators
LB: Fenoldopam is what class of drug and has what effects
D1 receptor agonist that causes decreased BP and increased HR. Given IV.
LB: Sildenafil, Vardenafil, and Tadalifil
Inhibit PDE type 5 resulting in vasodilation, can aid in erection
LB: Sudenafil, vardenafil, and tadalifil should be used in care with patients who use what drugs?
Beta blockers
Organic nitrates
CYP3A4 interacting drugs
LB: ACE inhibitors inhibit the production of what, and cause what net effects on the body?
Decreased angiotensin II leading to decreased TPR, decreased sodium and fluid retention, decreased BP, and increased HR
LB: What are adverse effects of inhibitors to the renin/angiotensin/aldosterone system?
Hyperkalemia
***Fetotoxicity
Hypersensitivity
LB: What side effect is common with all Vasodilators?
Hypotension
LB: When using an ACE Inhibitor, a patient sometimes has a dry cough. What causes this dry cough and what can you use to avoid it?
Bradykinin can lead to a cough, and blocking of ACE can lead to increased bradykinin concentrations
LB: What three diseases are Vasodilators and inhibitors of the renin/angiotensin/aldosterone system generally used for?
CHF
Hypertension
Angina/Ischemia
LB: What class of R/A/A effective drugs effects each part of the Renin/Angiotensin/Aldosterone pathway?
Angiotensinogen -> Angiotensin I - Aliskirin (Renin inhibitor)
Angiotensin I -> Angiotensin II - ACE Inhibitor
Angiotensin II receptors in body - AT-Receptor antagonists
LB: Match the drug or suffix to the drug class:
AT-Antagonist—————————————————Verapamil
Calcium channel blocker (dihydropyridine)—————Aliskirin
Calcium channel blocker (non-dihydropyridine)———Amlodipine
ACE Inhibitor—————————————————-Nitro
Phosphodiesterase inhibitor———————————(lo)sartan
Renin inhibitor—————————————————(lisin)opril
K channel blocker———————————————-(tadal)afil
Guanylyl cyclase activator————————————Minoxidil
AT-Antagonist—————————————————(lo)sartan
Calcium channel blocker (dihydropyridine)—————Amlodipine
Calcium channel blocker (non-dihydropyridine)———Verapamil
ACE Inhibitor—————————————————-(lisin)opril
Phosphodiesterase inhibitor———————————(tadal)afil
Renin inhibitor—————————————————Aliskirin
K channel blocker———————————————-Minoxidil
Guanylyl cyclase activator————————————nitro
