Beta Agonists Flashcards
Action
Bind to BETA2 receptors in the LUNGS –> increased smooth muscle relaxation and decreased inflammation
MOA
Block the BRONCHODILATION in the lungs caused by sympathetic NC stimulation and attach to receptors in the heart and lungs
Adverse effects
Tremor
TACHYcardia
HYPOkalemia
HYPERglycemia
Are adverse effects with beta agonists strong?
No, they are limited because of minimal systemic absorption and limited stimulation of B2 receptors on the HEART
Limited B2 stimulation on which organ causes beta agonists to have limited SEs?
HEART –> decreases systemic effects (along with decreased systemic absorption)
What happens with high-dose beta agonists?
There are higher risk of SEs because the drug diffuses into BS
Tremors are a SE for which type of beta agonist?
Nonselective (bc of increased sympathetic NS activation)
Why is TACHYcardia a SE of beta agonists?
Receptors in the SA node are stimulated
What are the names of some common short-acting beta agonists (SABAs)?
ProAir
Proventil
Ventolin (albuterol)
What is the suffix commonly associated with SABAs?
“-ol” like for BBs used to tx heart conditions
Why are SABAs used?
Active asthma flare because it bronchodilates the airways immediately
What are common forms of SABAs?
MDI
Nebulizer solution
Oral syrup
Oral tablet
SABA onset of action
5-10 min
SABA peak effect
MDI/neb: 1-2 hours
Oral: 0.25-3 hours
SABA duration of action
MDI/neb: 3-6 hours
Oral: 6-8 hours
SABA nebulizer vs pill…
Neb: straight to lungs (directly to target tissue so not as much systemic vasculature infusion, good absorption from capillaries)
Pill: increased systemic effects because in the BS, 1st pass effect
What is the name for a common long-acting beta agonist (LABA)?
Serevent (salmeterol)
What is the suffix commonly associated with LABAs?
“-ol”
What form do LABAs come in?
DPI
LABAs on set of action
30-60 min
LABAs peak effect
2-3 hours
LABAs duration of action
12 hours
Why is there a black box warning associated with LABAs?
Increased risk of death when used as the only agent to treat asthma –> should be combined with inhaled steroid
Is there a black box warning for LABAs when used to treat COPD?
No, they can be used as monotherapy to tx COPD
Why would someone use a LABA for asthma or for COPD?
Take it every day to control mucus and edema - for maintenance
