9-3-13 Flashcards
How do calcium channel blockers work?
Calcium flows in to muscle cells resulting in smooth muscle contraction and cardiac myocyte contraction.
Calcium channel blockers block calcium from entering muscle cells to reduce smooth muscle contraction and reduce myocyte contraction.
Cause reduced blood pressure!
What are the calcium channel blockers to remember?
Amlodipine - Norvasc
Nicardipine - Cardene
Where do calcium channel blockers differ?
Pharmacokinetics.
Effect on cardiac conduction.
Adverse drug reactions.
-Dihydropyridines - vascular side effects
-Non-dihydropyridines - cardiac conduction effects.
Indications for Amlodipine
Treatment of HTN
Treatment of symptomatic chronic stable angina, vasospastic angina.
Prevention of hospitalization due to angina with documented CAD.
Indications for Nicardipine (oral and intervenous)
Management of hypertension (immediate and sustained release products) - parenteral only for short-term use when oral treatment is not feasible.
Chronic stable angina (immediate-release product only).
Indications for Diltiazem (oral)
Primary HTN
Chronic stable angina or angina from coronary artery spasm.
Indications for Verapamil
Treatment of Hypertension
Angina pectoris (vasospastic, chronic, stable, unstable).
Supraventricular tachyarrhythmia (PSVT, atrial fibrillation/flutter)
What are examples of dyhydropyridines?
Amlodipine - Norvasc Clevidipine - Cleviprex Felodipine - Plendil Isradipine - Dynacirc CR Nicardipine - Cardene Nifedipine - Procardia Nimodipine - Nimotop
What is an example of phenylakylamine?
Verapamil - Isoptin
What is an example of a benzothiazepine?
Diltiazem - Cardizem
What are the advantages of calcium channel blockers?
No metabolic effects
No increase in lipid levels and safe in mild-to-moderate renal failure.
What are are the first line agents in newly diagnosed HTN patients with no other cardiovascular disease?
Diuretics
Then a choice of: ACEI; Calcium Channel Blocker, or Beta Blocker.
What are the adverse drug reactions of calcium channel blockers?
The AV node effect causing Bradycardia or tachyarrythmias (verapamil)
AV block.
The vascular effect:
- Excessive hypotension
- Dizziness
- Peripheral edema
Amlodipine
Amlodipine
10 mg
one tablet daily
Nircardipine Infusion
Nircardipine Infusion
Start at 5 mg/hour and titrate to effect every 15 minutes up to a maximum of 15 mg/hour
What drugs potentially interact with Verapamil?
Alpha-1 Blockers Amiodarone Dofetilide HMG-CoA reductase Inhibitors Midazolam
What is the lowest dose of Amlodipine?
2.5 mg per day
What is the max dose of Amlodipine?
10 mg per day
What drugs have potential interactions with all calcium channel blockers?
Beta Blockers
CYP34A Inhibitors
General Anesthetics
What drugs have potential interactions with Diltiazem?
Amiodarone
HMG-CoA Reductase Inhibitors
Midazolam
What is the usual maitainance dose of Nicardipine?
3mg/hour
How do ACE Inhibitors work?
Block the conversion of angiotensin I to angiotensin II which:
lowers arteriolar resistance,
increases venous capacity,
increases cardiac output and cardiac index, stroke work and volume,
lowers renovascular resistance
Reduce the progress of diabetic neuropathy.
Onset of Captopril
1-1.5 hours
Duration of Captopril
Dose Related
Half-Life of Captopril
1.9 hours
Protein Binding of Captopril
25-50%
Onset of Enalapril
1 hour
Duration of Enalapril
12 to 24 hours
Half Life of Enalapril
2 hours
Protein Binding of Enalapril
50%
Onset of Lisinopril
1 hour
Duration of Lisinopril
24 hours
What are the ACE Inhibitors to remember?
Lisinopril - Zestril
Captopril - Capoten
Ramipril - Altace
Half-Life of Lisinopril
11 to 12 hours
Protein Binding of Lisinopril
25%
Onset of Ramipril
1 to 2 hours
Duration of Ramipril
24 hours
Half-Life of Ramipril
13 to 17 hours
Protein Binding of Ramipril
73%
Does only Ramipril have a decease in mortality?
No! All ACEI have this effect.
Indications for Captopril
Management of hypertension.
Treatment of heart failure.
Left ventricular dysfunction after myocardial infarction.
Diabetic nephropathy.
Indications for Enalapril
Treatment of hypertension.
Treatment of symptomatic heart failure.
Treatment of asymptomatic left ventricular dysfunction.
Indications for Lisinopril
Treatment of hypertension, either alone or in combination with other antihypertensive agents.
Adjunctive therapy in treatment of heart failure.
Treatment of acute MI within 24 hours in hemodynamically-stable patients to improve survival.
Treatment of left ventricular dysfunction after MI
Indications for Ramipril
Treatment of hypertension, alone or in combination with a thiazide diuretic.
Treatment of left ventricular dysfunction after MI.
To reduce risk of MI, stroke, and death in patients at increased risk for these events.
Characteristics of ALL ACEI:
Have similar antihypertensive efficacy (Captopril is a short-acting agent as opposed to all other agents).
Reduce mortality in post-MI patients and help prevent the development of heart failure.
Contraindicated in pregnancy
Common side effects of ACEI
Cough Hyperkalemia Renal Impairment Hypotension Headache, dizziness, fatigue
Contraindications of ACEI
Bilateral renal artery stenosis
Previous angioedema associated with ACEI therapy.
What causes the nagging cough with ACEI?
increased levels of bradykinins
Lisinopril
Lisinopril
20 mg
one tablet daily
Captopril
Captopril
50 mg
one tablet three times a day
What are the angiotensin receptor blockers?
Losartan - Cozaar
Valsartan - Diovan
MOA of ARBs
Block the receptor site where angiotensin II activates all of the “bad” effects.
Blockade results in drop in blood pressure.
What is the max dose for Lisinopril?
40 mg (up to 80!)
What must you watch with Lisinopril therapy?
Potassium levels
Renal function
What is the max dose for Captopril?
100 mg
What are the differences in ARBs?
Dosing - all once per day dosing except for Losartan and Eposartan which can be once or twice per day.
For Heart Failure - only two are approved (Valsartan - Diovan, Candesartin-Atacand)
No differences in hypertension or potency.
Indications for Lorsatan
Treatment of HTN
Treatment of diabetic nephropahty in patients with type II diabetes mellitus and a history of HTN
Stroke risk reduction in patients with HTN and left ventricular hypertrophy.
Indications for Valsartan
Alone or in combination with other antihypertensive agents in the treatment of primary hypertension.
Reduction of cardiovascular mortality in patients with left ventricular dysfunction post -MI
Treatment of heart failure (NYHA Class II-IV)
Indications for Azilsartan
Treatment of hypertension; may be used alone or in combination with other antihypertensives.
What are positive characteristics of ARBs?
Dry cough incident rate drops.
What are ARBs adverse drug reactions?
Same as ACEIs
Cancer???
Are ARBs first-line drugs?
No!!! Not cost effective.
How do you choose an ARB?
The const efficient agent.
Interchangeability for hypertension versus heart failure.
What are the injectable ARBs?
None!
Valsartan
Valsartan
160 mg
one tablet daily
Max dose for Valsartan
320 mg
Losartan
Losartan
50 mg
one tablet daily
MOA of renin antagonists
Blockade of conversion of angiotensinogen to angiotensin I
What are the ADRs of renin agonists?
Same as ARBs and ACEIs
Who uses renin antagonists?
Patients who benefit from an ACEi or ARB and have become refractory.
EXPENSIVE!!
What is a renin antagonist?
Tekturna
Tekturna
Tekturna
300 mg
one tablet daily
What are good HTN combinations?
ACEIs and thiazides
ARBs and thiazides
ARBs and calcium channel blockers
calcium channel blockers and statins
When do you use “combos”?
Resist using unless patient struggles to adhere to drug therapy or when combination product is less expensive than taking the drugs separately.
