Respiratory

Question 1

What are the common indications for β2-agonists?

Answer 1

Asthma

Chronic Obstructive Pulmonary Disease

Hyperkalaemia
(nebulised salbutamol used as additional treatment)

Question 2

What are SABAs used for in Asthma + COPD?

Answer 2

To relieve breathlessness

Question 3

When and how would you use LABAs in asthma?

Answer 3

Used to treat chronic asthma when inhaled corticosteroids alone aren’t enough

LABA’s must always be given in conjunction w/ inhaled corticosteroids

Question 4

LABAs are used as 2nd line treatment which condition, to improve symptoms and reduce exacerbations?

Answer 4

COPD

Question 5

Where are β2-receptors are found where in the body?

Answer 5

Smooth muscle of;

bronchi

gut

uterus

blood vessels

Question 6

Name 2 SABAs

Answer 6

Salbutamol

Terbutaline

Question 7

Name 2 LABAs

Answer 7

Salmeterol

Formoterol

Question 8

How do β2-agonists improve airflow in constricted airways?

Answer 8

They stimulate the G protein-coupled receptor which activates a a cascade that lead to smooth muscle relaxation

Question 9

β2-agonists have a simile MOA to insulin win. what way?

This MOA makes it a useful adjunct in the treatment of which condition, particularly when IV access is difficult?

Answer 9

They both stimulate Na+/K+-adenosine triphosphatase (ATPase) pumps

Causing a shift of K+ from the extracellular to intracellular compartment.

Hyperkalaemia

Question 10

LABAs can cause which adverse effect?

Answer 10

Muscle cramps

Question 11

Activation of β2-receptors in other tissues accounts for the common ‘fight or flight’

What adverse effects can this cause?

Answer 11

Tachycardia

Palpitations

Anxiety

Tremor

Question 12

β2-agonists may increase the serum glucose concentration, at high doses serum lactate levels may also rise.

What is the MOA behind these adverse effects?

Answer 12

β2-agonists promote glycogenolysis

Question 13

Why do LABAs always need to be prescribed in conjunction w/ inhale corticosteroids?

Answer 13

Bc w/out a steroid they are associated w/ increased asthma deaths

Question 14

Which drug class may reduce the effectiveness of β2-agonists?

Answer 14

β2-Blockers

Question 15

Cautions should be taken when prescribing β2-agonists for patients with ▴cardiovascular disease.

Why?

Answer 15

Cautions should be taken w/ cardiovascular disease in pts whom Tachycardia (an adverse effect of B agonists) may provoke angina or arrhythmias

Question 16

Use of high-dose nebulised β2-agonists with in conjunction w/ what 2 drugs can lead to hypokalaemia?

To prevent this from happening what should be monitored in pts?

Answer 16

Theophylline

+

Corticosteroids

Monitor serum potassium concentrations