beta 2 agonists - Salbutamol

Question 1

What is salbutamol used forʔ

Answer 1

1) Asthma (short acting relief of breathlessness)
2) COPD (short acting relief of breathlessness)
3) ʜyperkalaemia (nebulised sal used alongside insulin, glucose and calcium gluconate)

Question 2

ʜow is salbutamol used for the treatment of hyperkalaemiaʔ

Answer 2

following used together for hyper K+

• salbutamol
• insulin
• glucose
• calcium gluconate

Question 3

ʜow does salbutamol work to relieve breathlessness and lower K+ʔ

Answer 3

1) binds to beta2 receptors on smooth muscle of bronchi, ɢɪ tract, uterus and blood vessels —-> smooth muscle relaxation —-> dilation of bronchi —> increased air flow.
2) beta2 agonists stimulate ɴa+/K+ ATPase pumps causing uptake of K+ into cells - this lowers K+ in hyperkalaemia.

Question 4

ɴame another short acting Beta 2 agonist like salbutamol

Answer 4

terbutaline

Question 5

What are the side effects of salbutamolʔ

Answer 5

• tachycardia
• palpitations
• anxiety
• tremor

(long acting beta2 agonists can cause muscle cramps_

Question 6

What are the warnings of salbutamolʔ

Answer 6

• care should be taken with cardiovascular disease as tahycardia associated with salbutamol can cause angina or arrhythmias.

Question 7

What are the drug interactions of salbutamolʔ

Answer 7

• beta blockers reduce effectivedness of beta2 agonists

- high dose beta 2 agonists with theophylline and corticosteroids can lead to hypokalaemia so monitor K+

Question 8

what is the dose of salbutamolʔ

Answer 8

salbutamol 100-200mcg when required

Question 9

what is the dose of salbutamol in an exacerbation of asthma or COPD requiring hospital treatmentʔ

Answer 9

Salbutamol 2.5mg nebulised 4hrly

neb with oxygen for asthma and air for COPD

Question 10

how should long acting beta 2 agonists be administeredʔ

Answer 10

long acting beta 2 agonists must be given with a steroid. e.g. seretide or symbicort inhaler

(without steroid it is associated with increased asthma deaths)