Antihypertensives Flashcards
What is the mechanism of action for the ACE-Inhibitors?
Angiotensin converting enzyme - Inhibitor
- Inhibits conversion of angiotensin-1 to angiotensin-2
- Causes vasodilation, decreased aldosterone levels, Na+ and fluid wasting and K+ retention
What is considered a normal BP?
SBP = <80
What BP would be considered to be prehypertension?
SBP = 120 - 139 or DBP = 80 - 89
What BP is considered to be Stage I HTN?
SBP = 140 - 159 or DBP = 90 - 99
What BP is considered to be Stage II HTN?
SBP = > or = to 160 or DBP = > or = to 100
What is the BP goal for a patient without co-morbid conditions?
< 140/90
What is the BP goal for a patient with diabetes, CKD, MI, angina, stroke, or heart failure?
< 130/80
What is the goal BP for a patient with proteinuria?
< 125/75
What is the goal BP for a patient with left ventricular hypertrophy?
< 120/80
What is the goal BP for a patient with isolated systolic HTN?
Treat with usual BP goals…
For patients with SBP >180, first goal is to reduce to <160 and monitor closely for hypotension. Then, attempt to reduce BP to target goal.
What are some drugs that may worsen HTN?
- Corticosteroids
- Oral contraceptives
- NSAIDs and COX-2 Inhibitors
- Erythropoietin
- Oral Decongestants
- Some antidepressants
- Cocaine and withdrawal from cocaine
- Nicotine and withdrawal from nicotine
- Amphetamines
What are some lifestyle modifications that can be done to reduce BP in patients?
- Weight reduction
- Dietary approaches to stop HTN
- Physical activity
- Dietary sodium reductions
- Reduce consumption of alcohol
What is the mechanism of action for the Alpha-2 Adrenergic Agonists?
Stimulates Alpha-2 receptors of the brain stem associated with autonomic regulation of CV system. Activation of Alpha-2 receptors causes neurons to quit releasing norepinephrine.
- Decreased sympathetic output
- Decreased BP
- Mildly decreases HR
What are some therapeutic uses for Alpha-2 Adrenergic Agonists?
Not 1st line for HTN, does not reduce M/M
- Clonidine tabs effective for HTN urgencies
- Clonidine used in treatment of withdrawal symptoms of nicotine, opiates, benzos, and alcohol.
- Methyldopa is DOC in pregnancy induced HTN
What are some adverse effects of the Alpha-2 Adrenergic Agonists?
- Orthostatic hypotension and dizziness, headache, and impaired ejaculation
- Anticholinergic: sedation, dry mouth, constipation, urinary retention, blurred vision
- Rebound fluid retention - add diuretic
- WARNING: Abrupt withdrawal causes severe rebound HTN. Taper over 3 - 4 days
What is the mechanism of action for the Alpha-1 Blockers?
Competitive blocking of the alpha-1 receptors.
HTN: lowers BP by causing vasodilation. Relaxes both arterial and venous smooth muscle surrounding some blood vessels.
BPH: Relax smooth muscle of the bladder neck & prostate, which improves urine flow in BPH
What are some therapeutic uses for Alpha-1 Blockers?
Not 1st line for HTN: does not reduce M/M
- Reduces BP well
- BPH: treats symptoms of urinary retention
- Raynaud’s disease
What are some adverse effects of Alpha-1 Blockers?
- Orthostatic hypotension: FIRST DOSE EFFECT - syncope following 1st dose…give at bedtime
- Reflex tachycardia
- Sodium and water retention
- Dizziness, lack of energy, drowsiness, nasal congestion, headache, decreased libido
What are some drug interactions of Alpha-1 Blockers?
- Use with vardenafil and sildenafil causes hypotension
- Alfuzosin is contraindicated with potent CYP3A4 inhibitors
What are the Alpha-2 Agonist drugs?
- clonidine
- methyldopa
What are the Alpha-1 Blocker drugs?
- doxazosin HTN/BPH
- alfuzosin BPH
- terazosin HTN/BPH
- tamsulosin BPH
- prazosin HTN
What are the Beta-1 Blocker drugs?
A - O in alphabet
- acebutolol
- atenolol
- betaxolol
- bisoprolol
- metoprolol
- nebivolol
What is the mechanism of action for the Beta-1 Blockers?
- Selectively block the Beta-1 receptors
- Higher affinity for Beta-1 receptors than Beta-2 receptors
- Decreased HR, decreased force of contraction
- Block juxtaglomerular cells - block renin release
What are the therapeutic uses for Beta-1 Blockers?
Preferred drug for HTN in pts. with cardiac co-morbidities such as:
- chronic unstable angina
- acute coronary syndrome
- post-MI
- systolic and diastolic CHF to improve M/M
- Atrial fibrillation and tachycardia
What are some other, non-cardiac therapeutic uses for Beta-1 Blockers?
- Hyperthyroidism to protect heart from excess adrenaline in patients with poorly controlled hyperthyroidism.
- Essential tremor
- Autonomic nervous system overload (stage fright; PTSD)
What are some adverse effects of Beta-1 Blockers?
- Hypotension
- sexual impairment
- nightmares
- Transient decreased HDL & increased Tg
- Acute heart failure, reduced cardiac output
- Bradycardia and AV block
- May mask S/S or hypoglycemia in diabetics
- WARNING: risk of fatal rebound HTN, tachycardia, angina, and MI with abrupt withdrawal. Taper over 1 - 2 weeks
Which patients must you use caution in when prescribing Beta-1 blockers in?
- Uncompensated heart failure
- AV block
- Diabetes
- Cardioselective Beta-blockers are safer than non-selective agents in pts with diabetes, peripheral vascular disease, asthma, and COPD
What are some drug interactions of Beta-1 Blockers?
- Additive AV blocking when given with digoxin, verapamil, or diltiazem
Which drugs may have intrinsic sympathomimetic activity?
Beta-1 blockers
- These have partial agonist activity
- Have little effect on resting HR, cardiac output, and Tg levels.
- Do not reduce CV risk like other Beta-blockers and may be detrimental post-MI.
What are the non-selective Beta-blockers?
Pinched Paul’s Nads
- propanolol
- nadolol
- pindolol
What is the mechanism of action for the non-selective Beta-blockers?
Same as Beta-blockers
- Selectively block the Beta-1, Beta-2, receptors
- Decreased HR, decreased force of contraction
- Block juxtaglomerular cells - block renin release
What are some therapeutic uses for the non-selective beta-blockers?
- chronic unstable angina
- acute coronary syndrome
- post-MI
- systolic and diastolic CHF to improve M/M
- Atrial fibrillation and tachycardia Cartelol and timolol are used as eye drops to treat glaucoma
- Hyperthyroidism to protect heart from excess adrenaline in patients with poorly controlled hyperthyroidism.
- Essential tremor
- Autonomic nervous system overload (stage fright; PTSD)
Which class of drugs may be used for migraine prophylaxis?
Non-selective beta-blockers
Which drugs may treat the following conditions?
- Hyperthyroidism to protect heart from excess adrenaline in patients with poorly controlled hyperthyroidism.
- Essential tremor
- Autonomic nervous system overload (stage fright; PTSD)
- chronic unstable angina
- acute coronary syndrome
- post-MI
- systolic and diastolic CHF to improve M/M
- Glaucoma
- Beta-1 Blockers
- non-selective Beta-blockers
What are some adverse effects that may be seen with Non-selective beta-blockers?
- Hypotension
- sexual impairment
- nightmares
- Transient decreased HDL & increased Tg
- Acute heart failure, reduced cardiac output
- Bradycardia and AV block
- May mask S/S or hypoglycemia in diabetics
- WARNING: risk of fatal rebound HTN, tachycardia, angina, and MI with abrupt withdrawal. Taper over 1 - 2 weeks
- Peripheral vasoconstriction
- Bronchoconstriction
- Hypoglycemia
- USE CAUTION: in asthma, COPD, PVD, decompensated heart failure, AV-block or fragile diabetes