Question Answer
What are Methylanthines? Methyl group added to enhance bronchodilation
What are the natural sources of xanthines? Tea(theophyline, most effective), Coffee(caffine), and Cocoa(theobromine)
What are the intended actions of xanthines? To relax smooth muscle
What are the Pulmonary effects of Methlxanthines? Inhibits bronchoconstriction, Reduces PVR(dilates pulmonary blood vessels), Enhances contraction and endurance of diaphragm
What are the CNS effect of Methylxanthines? Improves Respiratory drive, may cause anxiety, irritablity, insomnia, tremors, twiching and seizure. B6 may reduce CNS effects
What are the cardiac effects of Methylxanthines? Promote vasodilation of coronary arteries, may have + chronotropic and inotropic, can induce arrythmias, tachycardia, palpitations, improves stroke volume
What are the theraputic blood levels for asthma? COPD? 5-15 mcg/ml. 10-12 mcg/ml
Blood levels exceeding 30mcg/ml are associated with? Arrythmias and seizure
What are the toxic effects of Methylxanthines? Mild – nausea, headache, vomitingSerious – seizure/convultionsMay not be a step, may just have convultions
When cut the dose? When the half life is extended by CHF, fever, pneumonia or some meds
When to increase the dose? When half life is reduced by smokers, High protein diet, or in children(high metabolic rate)
Methylxanthine Meds include Theophylline, Aminophylline – H2O soluble, given IV
Theo-dur, Choledyl, and Lufyllin are? Most common PO methylxanthines
What is the effect of methylxanthines on eosinophils? Causes decreased migration
How many basic theories of action are there? Three
Other effects of methylxanthines? Diuretic