Adrenergics - Non-Catecholamines Flashcards
Are adrenergic non-catecholamines direct or indirect acting? Are they agonists or antagonists?
Direct
Agonists
What is the route of administration for phenylepherine? What are two exceptions?
Can be given orally
IV - when treating shock (hypotention)
Nasal decongestant comes in a nasal spray
What receptor does phenylepherine act on?
A1 only
What are the therapeutic effects of phenylepherine?
Increase BP (systolic and diastolic), decrease blood flow, decreases heart rate b/c of reflex from increased BP
What are the therapeutic uses of phenylepherine? (4) Which is the most significant and why?
Opthalmic - dilate pupil, decrease hemorrhage, conjunctivial decongestion
W/ local anesthetics to increase duration of action
Treatment of hypotention (in cases of shock) -> in this case would give IV
Nasal decongestant - most significant b/c OTC and is in an oral or nasal spray
What receptor does clonidine act on?
A2 - selective to CNS
What are the therapeutic effects of clonidine?
Decrease BP (prolonged) Decrease peripheral resistance, HR, and CO
What are the therapeutic uses of clonidine?
reduce sympathetic outflow (HTN)
What is the route of administration of clonidine?
can be given orally
What is the effect of clonidine when not in the CNS? and Why?
NOT AFFECTIVE!! It is a direct agonist of A2 receptors in the CNS and will not produce those effects outside of CNS. Works in post synaptic neurons in the CNS.
What are the side effects of clonidine?
Sedation, dry mouth, edema, rebound HTN with sudden discontinuation
What receptor does albuterol act on?
B2
What is the duration of action of albuterol?
3-6 hours - short acting
What is the major therapeutic effect and use of albuterol?
Bronchodilation in acute asthma attacks
What is the route of administration of albuterol?
Inhalation mainly
Also available as oral tablets
What are the side effects of albuterol?
Tachycardia, tremor, anxiety
What greatly reduces the side effects of albuterol?
Administration by inhalation
What are the significant substitutions to the chemical compound and why are they significant (2)?
CH2 b/f one of the OH groups -> not absorbed by catechol-methyltransferase so is relatively longer acting
Substitution on amine allows for selectivity of B2 over B1
What receptor does Salmeterol act on?
B2
What is the effect of salmeterol?
bronchodilation
What are the major therapeutic uses of salmeterol?
COPD, nocturnal asthma, persistent asthma
What is the duration of action of salmeterol? Why?
12h
Substitution on amine makes it very lipophilic -> means it hangs out in the lungs longer -> prevents metabolism
Not degraded by catechol-methylstransferase (b/c same substitution)
Is Salmeterol useful for acute asthma attacks?
No b/c slow onset of action
What is the mode of administration of salmeterol?
Inhalation
