What are the drugs that inhibit thiophylline metabolism? What drugs induce theophylline metabolism? What are the prototype histamine release inhibitors? What is cromolyn indicted for? What is the mechanism of cromolyn action? Why should cromolyn not be used for asthmatic attacks? Why is compliance difficult with cromolyn? What is the mechanism of action of corticosteroids? When should corticoid steroids not be used? what are the side effects of corticosteroids?

1. What are the drugs that inhibit thiophylline metabolism?

cirpoflaxin, norfloxacin, macrolides, cimentidine and rantidine, oral contraceptives

2. What drugs induce theophylline metabolism?

phenytoin (absorption inhibited), phenobarbitol, smoke (marijuana and tobacco)

3. What are the prototype histamine release inhibitors?

Cromolyn and Nedocromil

4. What is cromolyn indicted for?

the prophylactic anti-inflammatory agent

5. What is the mechanism of cromolyn action?

stabilizaton of the mast cell by preventing the Ca++ influx and thus preventing degranulation of the cells, and lowering the release of histamine leukotrienes and other inflammatory mediators

6. Why should cromolyn not be used for asthmatic attacks?

because it only effects the further release of the inflammatory mediators and not the ones already released

7. Why is compliance difficult with cromolyn?

because effect can take up to 4 weeks, to develop and the prophylactic agent does not allow effects to be easily seen and not dramatic

8. What is the mechanism of action of corticosteroids?

inhibit phospholipase A2 activity --> decreasing leukotriene synthesis, inhibits antibody production and release of hydrolytic enzymes from lysosomes, decreases inflammation of airways, increases edema, enhances activity of beta - 2 stimulants and protects against flair ups

9. When should corticoid steroids not be used?

ALONE for status asthmaticus; should be paired with a beta-2 stimulant

10. what are the side effects of corticosteroids?

complicating to other disease processes, sodium/water retention, worsens peptic ulcer disease, CHF, immunosuppression, blood glucose changes