Antihistamines Flashcards
what can be the consequence of severe histamine release?
Anaphalaxis
what can cause anaphalaxis?
Vaccines
Penicillins
insect bites
etc.
what occurs during anaphalaxis?
increase in vascular permeability
epiglottis edema, angiedema
vasodilation - shock
name some other allergy mediated diseases?
Atopic dermatitis
Cutaneous food adverse reactions
FAD
Other allergy mediated problems during surgery (e.g. morphine)
- premedication with ACP
describe the mechanism of action?
Inverse agonists H1 receptors
Not antagonists
indications for antihistamine usage?
individual differences
allergic diseases
respiratory diseases (Asthma, RAO, allergic bronchitis)
Anaphylactic reactions
classes of antihiatamines?
1st generation
2nd generation
which class is considered safer to use?
2nd generation
name some 1st generation substances?
hydroxyzine
diphenhydramine
chloropheniramine
Promethazine
name some second generation substances?
cetirizine
levocetirizine
loratadine
describe the pharmacokinetics?
good oral absorption (Cmax 2-3 hrs)
metabolised in the liver, induced by CYP450
side effects of using antihistamines?
CNS depression (1st gen)
Cardiac toxicity (1st gen)
Anticholinergic effect (1st gen)
Appetite depressant (cyproheptadine)
