E1: Agonist Drugs Flashcards
Phenylephrine
Indication
MOA
Pharm Effects
ADR
Indication: IV: hypotension/shock
MOA: Selectively binds to alpha-1 adrenergic receptors post-synaptically in effector cells
Pharm Effects
-Vascular smooth muscle receptor stimulation = vasoconstriction in blood vessels/arteries
-Vagal afferent induced decrease in HR
ADR
-CV: incres BP
-CNS: Nervousness, excitability, insomnia
-endocrine: hyperglycemia (alpha1 receptors in liver incres glucose production and decrease insulin secretion)
Clonidine
Indication
MOA
Pharm Effects
ADR
Indication:
-Hypertension (not first line)
-ADHD (ER-Kapavay)
MOA: Alpha-2a receptor stimulation pre-synaptically (autoreceptor)/ post-synaptically (CNS) decrease sympathetic tone; overall decrease sympathetic impulses in CNS
Pharm Effects:
-mostly CNS acting
-central inhibition of sympathetic tone (decrease #SNS impulses from brainstem) (decrease impulses to heart and blood vessels)
-decrease HR, SV, and decreased blood vessel constriction
-binds imidazoline (I1) receptors to decrease NE release
ADR:
-CNS: excessive sedation, fatigue, headache
-orthostatic/ postural hypotension ( avoid in elderly)
-anticholinergic side effects
Methyldopa (Aldomet)
Indication
MOA
Pharm Effects
ADR
Indication:
-HTN in pregnancy
MOA
Alpha-2 receptor stimulation presynaptically (autoreceptor)/postsynaptically (CNS) decrease sympathetic impulses (DECREASE NE release)
Pharm effects
-prodrug
-active metabolite: alpha methyl norepinephrine), active in CNS
-alpha2 agonist
-no beta activity
-decreased vasoconstriction w/less effect on heart than clonidine
ADR:
-Drowsiness (common)
-decreased mental alertness, lapses of memory
-anticholinergic ADR: sedation/dry mouth
Pseudoephedrine-Sudafed
Indication
MOA
Pharm Effects
ADR
Indication: Nasal rhinitis
MOA:
indirect agonist
-inhibit NET
-releasing agent: causes the release of NE from vesicles in presynaptic neurons (displaced NE released into synapse)
Pharm Effects:
-nasal blood vessels: decrease sections and decrease vasodilation in nose
- vascular smooth muscle NE receptor stimulation à vasoconstriction in blood vessel arteries
-vagal afferent induced decrease in HR and CO
ADR
-CV: increased BP
- CNS: nervousness, excitability, insomnia
-endocrine: hyperglycemia
Dobutamine (Dobutrex)
Indication
MOA
Pharm Effects
ADR
Indication: IV short term use in cases of heart failure to support cardiac function
MOA
-Beta-1 stimulation of cardiac cells»_space; beta2, alpha1
-increase cAMP –> PKA –> [Ca++]
-Ca++ induced Ca++ release from SR
Actin + myosin shortening of cardiac muscle fibers –> contraction
Pharm Effects
Inotropic agent (increase force of contraction)
Less chronotropic actions (rate)
** alpha1, beta2 stimulation only observed at higher doses that are not commonly used
ADR
CV: extension of effect
-↑HR
↑SBP
↑premature ventricular contractions (PVCs)
Isoproterenol
Indication
MOA
Pharm Effects
ADR
Indication:
-heart block/bradycardia
-cardiogenic shock
-bronchospasm
MOA
Binds non-selectively to beta-1 and beta-2 adrenergic receptors
Pharm Effects
-positive inotropic (force) and chronotropic (rate) effects in heart
-lowers peripheral vascular resistance and diastolic pressures
-prevents/relieves bronchoconstriction
-BP typically falls
ADR
CV: syncope, tachyarrhythmia
Neurological: confusion, headache, tremor
Norepinephrine-Levophed IV
Indication
MOA
Pharm Effects
ADR
Indication: Maintain BP in acute hypotensive states
MOA: Stimulates both alpha and beta receptors (alpha1, alpha2, beta1»_space;> beta2)
Pharm Effects
-Vasoconstriction → ↑ BP
-inotropic and chronotropic effects on heart → ↑ BP
-compensatory vagal reflex slows HR overcoming direct beta-1 stimulating effects
ADR
Bradycardia
Ischemia and necrosis at site of injection
Epinephrine
Indication
MOA
Pharm Effects in eye
ADR
Indication
-shock: ↑BP (IV 1mg/ml soln)
-anaphylaxis/ allergic reaction (Epipen)
-Reversal of acute hypersensitivity reaction
-Adrenalin nasal soln 0.1%
- epi and lidocaine-xylocaine (Dental SQ); local vasoconstriction to ↑ duration of anesthetic and allow for lower anesthetic dose
MOA
Binds non-selectively to all adrenergic receptors (alpha-1, alpha-2, beta-1, beta-2, beta-3)
Pharm Effects
-stimulation is dose dependent
Beta-2 occupied first, then beta-1.. then alpha-1
-eye
–pupil: alpha-1 transient mydriasis
– ↓IOP
—- alpha2 ↓aq production
—-beta1 ↑ aq production
—- beta2 ↑ aq outflow
–ocular decongestant: alpha1 constriction of blood vessels
ADR:
CV: HTN, tachycardia, arrhythmias, stroke, cardiac ischemia –> MI
CNS: anxiety, apprehension, dizziness
Endocrine: ↑blood glucose (alpha-2 inhibits insulin secretion)
*sympathomimetic s also stimulate the liver to secrete glucose
Epinephrine
Indication
MOA
Pharm Effects in arteries and veins
ADR
Indication
-shock: ↑BP (IV 1mg/ml soln)
-anaphylaxis/ allergic reaction (Epipen)
-Reversal of acute hypersensitivity reaction
-Adrenalin nasal soln 0.1%
- epi and lidocaine-xylocaine (Dental SQ); local vasoconstriction to ↑ duration of anesthetic and allow for lower anesthetic dose
MOA
Binds non-selectively to all adrenergic receptors (alpha-1, alpha-2, beta-1, beta-2, beta-3)
Pharm Effects
-stimulation is dose dependent
Beta-2 occupied first, then beta-1.. then alpha-1
-arteries/veins (alpha1 vasoconstriction ↑BP) (lesser B2 vasodilation to ↓BP)
ADR:
CV: HTN, tachycardia, arrhythmias, stroke, cardiac ischemia –> MI
CNS: anxiety, apprehension, dizziness
Endocrine: ↑blood glucose (alpha-2 inhibits insulin secretion)
*sympathomimetic s also stimulate the liver to secrete glucose
Epinephrine
Indication
MOA
Pharm Effects in lung
ADR
Indication
-shock: ↑BP (IV 1mg/ml soln)
-anaphylaxis/ allergic reaction (Epipen)
-Reversal of acute hypersensitivity reaction
-Adrenalin nasal soln 0.1%
- epi and lidocaine-xylocaine (Dental SQ); local vasoconstriction to ↑ duration of anesthetic and allow for lower anesthetic dose
MOA
Binds non-selectively to all adrenergic receptors (alpha-1, alpha-2, beta-1, beta-2, beta-3)
Pharm Effects
-stimulation is dose dependent
Beta-2 occupied first, then beta-1.. then alpha-1
-lung: B2 bronchodilation
Alpha-1 reducing congestion/edema of bronchial mucosa
ADR:
CV: HTN, tachycardia, arrhythmias, stroke, cardiac ischemia –> MI
CNS: anxiety, apprehension, dizziness
Endocrine: ↑blood glucose (alpha-2 inhibits insulin secretion)
*sympathomimetic s also stimulate the liver to secrete glucose
Epinephrine
Indication
MOA
Pharm Effects in heart
ADR
Indication
-shock: ↑BP (IV 1mg/ml soln)
-anaphylaxis/ allergic reaction (Epipen)
-Reversal of acute hypersensitivity reaction
-Adrenalin nasal soln 0.1%
- epi and lidocaine-xylocaine (Dental SQ); local vasoconstriction to ↑ duration of anesthetic and allow for lower anesthetic dose
MOA
Binds non-selectively to all adrenergic receptors (alpha-1, alpha-2, beta-1, beta-2, beta-3)
Pharm Effects
-stimulation is dose dependent
Beta-2 occupied first, then beta-1.. then alpha-1
-heart (mostly B1 stimulation, some B2)
–↑ chronotropic and inotropic effect
ADR:
CV: HTN, tachycardia, arrhythmias, stroke, cardiac ischemia –> MI
CNS: anxiety, apprehension, dizziness
Endocrine: ↑blood glucose (alpha-2 inhibits insulin secretion)
*sympathomimetic s also stimulate the liver to secrete glucose
Epinephrine
Indication
MOA
Pharm Effects in anaphylaxis
ADR
Indication
-shock: ↑BP (IV 1mg/ml soln)
-anaphylaxis/ allergic reaction (Epipen)
-Reversal of acute hypersensitivity reaction
-Adrenalin nasal soln 0.1%
- epi and lidocaine-xylocaine (Dental SQ); local vasoconstriction to ↑ duration of anesthetic and allow for lower anesthetic dose
MOA
Binds non-selectively to all adrenergic receptors (alpha-1, alpha-2, beta-1, beta-2, beta-3)
Pharm Effects
-stimulation is dose dependent
Beta-2 occupied first, then beta-1.. then alpha-1
-anaphylaxis/allergic reaction; rapids relief of hypersensitivity reactions, epi causes vasoconstriction to ↓ swelling; suppresses release of histamine from mast cells
ADR:
CV: HTN, tachycardia, arrhythmias, stroke, cardiac ischemia –> MI
CNS: anxiety, apprehension, dizziness
Endocrine: ↑blood glucose (alpha-2 inhibits insulin secretion)
*sympathomimetic s also stimulate the liver to secrete glucose
Dopamine
Indication
MOA
Pharm Effects
ADR
Indication: Heart failure patients w/hypotension
MOA
Dose dependent stimulation DA-1, B1, B2, alpha-1
Pharm Effects
Low dose: stimulate DA-1 only
-renal and mesenteric vasodilation, results in ↑ renal perfusion and natriuresis in sever heart failure
Moderate dose: stimulate DA-1, B1, B2
-↑ heart rate and force of contraction
High dose: stimulate DA-1, B1, B2, α1 receptors
-↑systemic vascular resistance
- ↑ BP
ADR
CV: angina, A. Fib, hypotension, tachycardia
CNS: anxiety, headache
GI: N,V
Fenoldopam-Corlopam
Indication
MOA
Pharm Effects
ADR
Indication: Hypertensive crisis
MOA
Primarily Dopamine-1 (DA-1)
Minimal adrenergic activity
Pharm Effects
-Rapid-acting arterial vasodilation in renal blood vessels –> ↓blood pressure
-sodium excretion in nephron
-improves renal perfusion
ADR
CV: hypotension, tachycardia
HA, flushing
Phenylephrine DI
-MAO/COMT inhibitors
-TCA’s
