pharm module 6: HTN

what is the first line therapy for hypertension?

• diuretics: hydrochlorothiazide 

• angiotensin converting enzyme inhibitors 

• angiotenson receptor blockers 

• calcium channel blockers 

second line of therapy for hypertension

• beta blockers

• alpha 2 agonists

• direct vasodilators

what is primary hypertension?

• no identifiable cause, > 90% have this type

what is secondary hypertension?

• cause identified

  • cushings syndrome

  • hyperthyroidism

  • chronic renal disease

  • certain drugs (corticosteroids, caffeine, oral contraceptives, decongestants)

what are some ace inhibitors?

• captopril (capoten)

• enalapril, lisinopril

MOA Ace inhibitors

• inhibvits angiotensin 1 conversion to 2 (active)

• helps with formation of vasodilation, substances bradykinins and prostaglandins

• role in kidney protection: preferentially dilate efferent arterioles relieves intraglomerular pressure

What are ace inhibitors used for disease wise?

• hypertension

• heart failure

what is the black box warning of ace inhibitors 

• fetal injury and death may occur when ACE inhibitors or ARBs are taken during pregnancy 

ACE inhibitors adverse effects

• orthostatic hypotension

• persistent cough (due to bradykinin, which is a proinflammatory substance)

• hyperkalemia (due to the decrease in aldosterone production)

• fetal injury (category X)

• angioedema (swellng around lips, eyes, throat - watch for airway)

wat should you assess before giving ACE inhibitors?

• assess potassium level prior to starting

what should you assess while giving ACE inhibitors?

• monitor for cough and monitor for angioedema

pt teaching for ACE inhibitors?

• report swelling in the facial area immediately

• do not become pregnant while taking 

• do not consume salt substitutes 

• rise slowly from seated positions 

what are some ARB inhibitors?

• Losartan (cozaar)

• valsartan (diovan)

MOA for ARB inhibitors?

• blocks the action of angiotensin 2 - blood vessels, adrenal glands, and other tissues 

black box warning for ARB inhibitors

• fetal injury and death may occur when ACE inhibitors or ARBs are taken during pregnancy. renal artery stenosis

ARB inhibitor adverse effects

• orthostatic hypotension

• elevated potassium

• angioedema

• fetal injury

arb inhibitors what should you assess for?

• evaluate potassium level (3.5-5)

• assess for angioedema

• instruct pt to avoid pregnancy while taking

what are the types of non-selective calcium channel blockers?

• verapamil

• diltiazem 

MOA of non-selective calcium channel blockers

• block the movement of calcium in a nonselective way 

• non-selective = affect arterioles (which is the target we are treating) and slow the cardiac conduction system (largely used for the heart, but found that it can also decrease BP)

what are some drug-drug interactions for non-selective calcium channel blockers?

• other antihypertensives 

• HCTZ

• NSAIDs

adverse effects of non-selective calcium channel blockers?

• constipation (due to relaxing the muscle of the gut)

• bradycardia (due to its affect on the cardiac muscle)

what should you assess when giving non-selective calcium channel blockers?

• monitor HR for bradycardia

• assess peripheral edema 

• instruct pt about risks of constipation

what are some selective calcium channel blockers?

• amlodipine

• nifedipine

where do selectiv ecalcium channel blockers target?

• they target in arterioles 

MOA of selective calcium channel blockers

• selectively block the movement of calcium only in the arterioles (which is the target)

• can activate the baroreceptor reflex (bc CCBs result in a decrease in BP, the baroreceptor reflex often initiated a reflexive increase in sympathetic activity leading to increased HR and contractility)

What should selective calcium channel blockers be used for?

• angina 

• HTN 

adverse effects of selective calcium channel blockers?

• reflex tachycardia

• hypotension 

• peripheral edema 

• nausea 

• flushing 

• dizziness

• lightheadedness

drug-drug for selective calcium channel blockers

• digoxin can cause digi tox

• beta blcokers can counteract reflex tachycardia 

  • can cause increase risk for HF

nursing care/pt teaching for calcium channel blockers selective

• instruct pt to report dizziness

• change position slowly 

• assess for reflex tachycardia 

• assess for edema 

beta blockers MOA

• bind to receptors located in cardiac nodal tissue, conduction tissue and mycocytes 

• slows nerve impulses that travel through the heart. as a result, your heart does not have to work as hard because it needs less blood and oxygen. beta-blockers also block the impulses that can cause arrhythmias (slows down the HR)

what are the 2 main beta receptors?

• beta 1 (cardiac/vascular tissue)

• beta 2 (lungs and smooth muscles)

selective beta blockers

• atenolol

• metoprolol

• nebivol (bystolic)

  • they primarily block beta 1

non-selective beta blockers

• propanolol (inderal)

• carvedilol (coreg)

• labetolol 

  • exert beta 1 and bets 2 receptors 

  • this categary also impacts smooth muscles (ex: lungs)

what are beta blockers used for?

• proven ability to reduce complications of HTN 

• low incidence of severe adverse effects 

what specifically are beta blockers used to target/ease?

• angina (Eases sx by decreasinf hearts workload) post MI

• dysrhythmias (by slowing conduction to the myocardium)

• tremors, anxiety, stage fright (slows down HR, decreases s/s fights or flight)

• hyperthyroid (slows down HR), pheochromocytoma (decreases BP, this is due to tumor in kidney)

adverse effect of selective beta blockers

• these are beta 1 = heart only

  • cardiac effects - bradycardia 

  • hypotension 

  • hypoglycemia unawareness (Can mask signs of hypoglycemia) - educate diabetics

adverse effects of non-selective beta blockers

• cardiac effects - breadycarida, AV block 

• hypotension 

• bronchial effects - wheezing 

• hyperglycemia - specifically propanolol 

• hypoglycemia unawareness

some drug interactions with beta blockers

• calcium channel blockers (could cause an additional effect on BP)

what should you assess for when giving beta blockers?

• assess for contraindications (decreases HR, asthma, COPD) - it can worsen breathing problems 

• assess HR and BP 

• monitor for bronchoconstriction with non-selective 

• monitor for CNS effects (depression, insomnia, nightmares)

pt instructions for beta blockers

• early signs of heart failure 

• not to abruptly discontinue (could result in rebound HTN, HF, and angina)

doxazosin trade name

cardura

doxazosin (Cardura) - alpha 1 blocker MOA

• receptors in vascular smooth muscle, it has few adverse effects on other autonomic organs and is preferred over non-selective beta blockers 

• doxazosin dilates arteries and veins and is capable of causing a rapid fall in BP 

• alsu used for BPH 

adverse effects for doxazosin (cardura)

• dizzy 

• dyspnea 

• asthenia 

• headache 

• hypotension/orthostatic 

• somnolence

what to assess when gicing doxazosin?

• first doses - moniot for profound hypotension and possible syncope during 2-6 doses (causes rapid decrease in BP)

• swallow cardura XL whole: do not crush, chew, or split the tablet 

hydralazine trade name

apresoline

what is hydralazine NOT?

not a diuretic

MOA of hydralazine (apresoline) - direct vasodilator/CCb

• direct arteriole relaxation, causes reflex sympathetic effects (reflex tachycardia) - nervous system acts fast bc of this 

• hypotensice effects diminish over time 

• reserved as 3rd or 4th line therapy in resistant HTN 

• should be administered with food

what route do you take hydralazine?

• oral 

• IV

what do you have to consider when giving hydralazine to different pts?

• how they metabolize the medicine thus questioning when to give the next dose 

hydralazine why is it given?

• HTN not controlled by other meds 

adverse effects of hydralazine (apresoline)

• increases sodium and water retention 

• palpitations, reflex tachycardia (used with beta blocker) temporary agranulocytosis

• N/D

• postural instability

• systemic lupus erythematosus like syndrome

what should you monitor when giving hydralazine?

• HF

• urinary output 

• lupus like syndrome 

pt instructions for hydralazine (apresoline)

• make position changes slowly 

• avoid hot baths/showers

What meds should you avoid when taking HTN meds?

• psuedoephidrine (sudafed)

  • sympathominmetic 

• NSAIDs (motrin, aleve)

  • prostaglandin blocker 

Get approvel from physician, even otc durgs