Selective B-2 Agonists Flashcards
Where do we see relaxation from our selective B2 agonists?
Bronchiole smooth muscle and uterine smooth muscle.
What kind of DOA do B2 agonists have and why?
Sustained DOA due to different placements of their hydroxyl groups on the benzene ring. They are not metabolized by COMT.
What routes of administration are used for B2 agonists?
PO, inhalational, SQ or IV.
Which ROA is the most common? Which is the least common and when would we use it?
Most common is inhalational.
Least common is IV and we only use it when the bronchioles are so constricted that we can’t get the inhalational in.
What side effects do we see from B2 agonists? Make sure to mention the receptor.
- Tremor (B2 in skeletal muscle)
2. Reflex tachycardia (vasodilation and B2 in heart, baroreceptor reflex and small B1 action).
What drug is the prototype for selective Beta 2 agonists?
Albuterol
When is albuterol the preferred choice?
Bronchospasm due to asthma.
What is the dose of albuterol?
MD1: 100mcg per puff. 2 puffs every 4-6 hours. max 16-20 puffs.
For life threatening asthma what dose of albuterol do we use?
Nebulization of 15mg/hr for 2 hours.
What two side effects do we see with large doses of albuterol?
tachycardia and hypokalemia.
When is terbutaline used? ROA and dose?
For asthma or premature labor
Oral, SC (.25mg) or puffs.
How is salmeterol given? DOA? What do we worry about with people taking steroids?
- MDI
- DOA is over 12 hours
- Sudden death from bronchospasm
When has ritordine been used? What other receptor can it hit and what side effects do we worry about?
- Premature labor
- Some beta 1 activity thus increase HR and CO
- Can cause pulmonary edema due to decreased excretion of potassium, sodium and H2O.
