Asthama drugs

Question 1

Theophylline adverse reaction

Answer 1

Adenosine antagonism can cause ventricular arrhythmia and tachyarrhythmia (can be life threatening)

Question 2

Glucocorticoids MOA

Answer 2

Reduce integrins thus reduce leukocyte migration and permeability of capillaries. Thus reduce inflammation.

Question 3

Biochemical action of glucocorticoids

Answer 3

inhibitis PLA2 (phospholipase A2), the enzyme responsible for breaking down PGs and LTs

reduce expression of COX2, IL-2, platelet activating factor

Question 4

Sudden withdrawl of Glucocorticoid therapy can result in…

Answer 4

SHOCK, because glucocorticoids suppress ACTH secretion from pituitary. Sudden withdrawal results in state of adrenal deficiency.

Question 5

Other major side effects of Glucocorticoids

Answer 5

Hyperglycemia
Cushing’s syndrome*** (buffalo hump)
Osteoporosis
Gastrointestinal acid increase (due to PG suppression)

Question 6

Drugs to prevent asthma attacks

Answer 6

Drugs that inhibit Bronchoconstriction

Ipratropium: inhibits ACh at M3 receptors
Theophylline: inhibits Adenosine
Leukasts or Zileuton: inhibits Leukotrienes at LTC4 or D4 receptors

these only work BEFORE onset. During attack, these are useless.

Question 7

Drugs to deal with onset asthma attack

Answer 7

Beta2 receptor Agonists that cause Bronchodilation

by way of increasing cAMP

Question 8

Theophylline mode of action

Answer 8

Bronchodilates by inhibition of phosphodiesterase

Prevents bronchospasm by antagonism of adenosine