histamine 2nd generation

Question 1

advantages of 2nd gen over 1st generation

Answer 1

non/less-sedating
faster onset of action
longer lasting- dosing only once or twice daily

Question 2

role in therapy

Answer 2

second generation good for managing EENT symptoms

but first generation may be preferred with CNS effects are desired

Question 3

loratadine

Answer 3

MOA: blocks the effects of H1 receptors in many tissues
more antimuscarinic than other 2nd generation antihistamines so more drying
indications: seasonal allergic rhinitis, urticaria

Question 4

loratadine metabolized

Answer 4

to active metabolite and has a high first pass effect:
-metabolized by CYP3A4
into desloratadine with a t1/2 life of 27 hrs

Question 5

cetirizine

Answer 5

zyrtec
active metabolite of hydroxyzine
drowsiness is dose related this is a less sedating and considered very clean

Question 6

fexofenadine

Answer 6

allegra
active metabolite of terfenadine
best taken on an empty stomach -bioavalibility reduced by high fat meal (50%) and various fruit juice (36%)
onset 1-2 hrs