Ch.8 Xanthines Flashcards
What are alkaloids
Group of alkaline substances from plants which reacts with acids to form salts like theophylline
What are methylxanthines and the 3 methylated xanthines
Drugs derived from xanthines
Caffeine, theophylline, and theobromine
What can theophylline treat
Asthma, COPD, apnea of prematurity
What is the xanthine choice to treat apnea of prematurity
Caffeine citrate
Why is theophylline classified as a bronchodilator
Because it has a relaxing effect on bronchial smooth muscles
Why is caffeine the strongest drug
It stimulates skeletal muscles and the central nervous system
What are the 3 mechanisms of action for theophylline and xanthines that reverse airway obstruction
1 inhibits phosphodiesterase~ *cAMP causes bronchial smooth muscle relaxation *
2 blockade of adenosine receptors
3. Catecholamine release
What is the side effect in > 20 ug/ ml serum level of theophylline
Side effect would be nausea
What is the recommended blood serum of theophylline level for management of asthma
5-15 ug/ml
What is the recommended blood serum of theophylline level for management of COPd
5-10 ug/ml
Why is theophylline difficult to titrate dosages
Individuals metabolize theophylline at different rates.
It has a narrow therapeutic margin
What are the 6 common side effects of theophylline
Headache-CNS
Anxiety- CNS
Diuresis- renal
Tachypnea- resp
Palpitations- cardiovascular
Vomiting
What factors affect theophylline
Renal failure will cause an increase in blood theophylline levels
What conditions increase theophylline blood levels
Pneumonia
Corticosteroids
B blockers
What does theophylline produce
1 increase in force of resp muscle contractility
2 theophylline produces an increase in resp muscle strength and endurance
3 increase in ventilatory drive at CNS
4 cardiovascular effect
5 anti inflammatory
