chapter 15: Adrenergic Agonist

Question 1

adrenergic agonists

Answer 1

Alpha-agonists- stimulate alpha receptors on target organ
Beta agonists- stimulate beta receptors on target organ
These stimulate ALL of the adrenergic receptors (sympathomimetics)

Question 2

adrenergc agonists therapuetic actions

Answer 2

Heart- Increased HR, contractility
Lung- Bronchioles dilate, RR and depth increases
Blood vessels- constrict (increases BP)
Eyes- Intraocular pressure decreases; pupils dilate
Liver- Glycogenolysis (into glucose for energy)
Skin- Sweating decrease

Question 3

indications for adrenergic agonists

Answer 3

Treatment of:
hypotension/shock/ bradycardia
Bronchospasm
Anaphylaxis

Question 4

a1 receptor locations

Answer 4

eye, arterioles -constrict, veins —constrict, skin, visera, muscous mmbranes, male sex organs, prostate, bladder

Question 5

a2 receptor locations

Answer 5

centrally acting receptor (bain) -inhibit NE release

Question 6

b1 receptor locations

Answer 6

heart
kidney -increase renin release, increase BP

Question 7

B2 receptor locations

Answer 7

lungs/bronchi -broncodialtion
liver -glycogenolysis, increase BG
arterioles -dilation
heart
skel mm
uterus

Question 8

catecholamines

Answer 8

Epinephrine
Norepinephrine
Isoproterenol
Dopamine
Dobutamine

have a catecholnucleus
cannot be given orally (natural)
shorter duration of action bc these are metabolised by COMt and MAO
polar subst. cannot cross the BBB -no direct stimulant action on CNS
they act directly on adrenergic receptors

Question 9

non-catecholamines

Answer 9

Phenylephrine
pseudoephedrine
Albuterol
Ephedrine

minic cates
can be given orally
duration of action i longer bc not metabolismed by COMT and MAO
these crss the BBB and have a stimulant effect on CNS
act both directly, indirectly, adnd mixed action on adrenergic receptors

Question 10

Epi

Answer 10

Routes: SQ, IV, Topically, inhalation, intracardiac. (Not given orally)

MOA: Stimulates alpha and beta adrenergic receptors. Non-selective A1. A2, B1, B2)

Chemical class: Catecholamine

Use: Emergencies, anaphylactic Shock **, increases cardiac contraction and cardiac output, heart rate, blood pressure, vasoconstriction,
Alpha 1 = Controls bleeding and elevates BP
B1- Heart rate contraction
B2 Lung- bronchodilation.
SE: Nervousness, tremors, tachycardia, hypertension, angina, hyperglycemia

Question 11

what happens when a drug stimulatns A1 and A2

Answer 11

A1 prevails

Question 12

NE (levophed

Answer 12

Routes: SQ, IV, inhalation, intracardiac. (Not given orally)

MOA: Stimulates alpha and beta (ONE only) adrenergic receptors.

Non-selective a1, a2, b1 (NOT B2)

Chemical class: Catecholamine

Use: Only for: hypotensive states and cardiac arrest

SE: Less than Epi

Question 13

isoproterenol

Answer 13

Routes: IV. (Not given orally)

MOA: Stimulates beta 1 & 2 adrenergic receptors.

Chemical class: Catecholamine

Use: Cardiovascular disorders (AV heart block), cardiogenic shock

SE: Less than Epi and norepi

Question 14

dopamine

Answer 14

Routes: IV. (Not given orally)

MOA: Stimulates beta 1 & high doses A1 adrenergic receptors.

Chemical class: Catecholamine

Use: Shock,** dilate renal blood vessels, heart failure

SE: Tachycardia, dysrhythmias and anginal pain

• given at very high dose –vasoconstrictions. Constricts renal BF -> decreased renal perfusion -> renal injury

Question 15

dobutamine

Answer 15

Routes: IV. (Not given orally)

MOA: Stimulates beta 1

Chemical class: Catecholamine

Use: Only indication is heart Failure

SE: Tachycardia

Question 16

phenylepherine

Answer 16

Other name: Neo-synephrine

Routes: Locally, IV. (Not given orally) Can be sed as a local vasocontrictor like nasal spring

MOA: a1.

Chemical class: Non-catecholamine

Use: Shock, dilate renal blood vessels, heart failure

SE: Tachycardia, dysrhythmias and anginal pain

Question 17

ephedrine

Answer 17

Routes: IV, PO

MOA: Stimulates a1, a2, b1, b2 adrenergic receptors.

Chemical class: Non-Catecholamine

Use: Same as epi

SE: Same as epi

was used as a diet pill —decreas appitite and weight

Question 18

B2 adrenergic agonist

Answer 18

Beta 2 receptor
Agonist

Lungs
Response: Relaxation of smooth muscle and bronchodilation
Use: Mainly to treat bronchospasm and bronchoconstriction
SE: Tachycardia, nervousness

Question 19

albuterol (proventil, ventolin, proair)

Answer 19

Routes: PO and inhalation

Selective
Acts on β2 adrenergic receptors, SABA
Relaxing airway smooth muscles

Uses: Treat bronchospasm, asthma, COPD
recuse inhalor

SE: Tremor, nervousness, restlessness, tachycardia, palpitations