L1: Allergic rhinitis Flashcards
this is the inflammation of the Nasal mucous membrane due to exposure to inhaled allergens
allergic rhinitis
in allergic rhinitis, inhaled allergenic particles comes into contact to the mucous membranes which elicits a specific response mediated by ___ which causes the release of inflammatory mediators
immunoglobulin E
what are the 2 types of allergic rhinitis?
seasonal allergic rhinitis (hay fever)
and
persistent allergic rhinitis (perennial rhinitis)
3 parts of its pathophysiology
I. Sensitization to an allergen
II. Early phase response
III. Late phase response
th2-type cytokines
IL 3, 4, 5, 9, 13
responsible for class switcging of B cells to produce IgE
IL 4, and IL 13
responsible for eosinophil recruitment, activation, and survival
IL 5
IgE will bind to IgE receptors located in the —-(3) which sensitizes the cells
mast cells, basophils, and eosinophils
patients who have high levels of these 2 means that they have an allergic reaction
high eosinophil count and IgE levels
onset and duration of early phase response
onset: within minutes
duration >1hr
early phase response involves the ____ of mast cells, basophils, and eosinophils
degranulation
onset and duration of late phase response
onset: 4-8hrs
duration: 24hrs
allergic rhinitis symptoms
clear rhinorrhea
Nasal congestion
Sneezing
postnasal drip
allergic conjuctivitis
pruritic eyes, ears, nose, and palate
tinnitus
occurs due to constant rubbing of the nose
transverse crease
redness or blackeye around the eyes
allergic shiners
10-40% prevalence
asthma
refers to mouth reathing and snoring
adenoidal breathing
what is detected in microscopic examination of allergic rhinitis
eosinophils
immediate-type hypersensitivity skin test wherein diluted allergen is pricked or scratched into the skin surface
percutaneous route
immediate type hypersensitivity skin test wherein a small volume, 0.01 to 0.05mL, of diluted allergen is injected between the layers of skin
intradermal route
positive reaction of allergy testing
wheal-and-flare reaction
in allergy testing ___ meds should be dc
antihistamine meds
first commonly used method for detecting IgE antivodies in the blood that are specific for a given allergen
Radioallergosorbent test (RAST)
RAST measures the levels of _____ produced when your blood js mixed with a series of allergens in a laboratory
allergy antibody, or IgE
maintain household humidity below __%
50%
competitively antagonists to histamine binding to H1 receptors, without acrivating them
H1 receptor antagonist
Anticholinergic properties of H1RA
dec Nasal, salivary, lacrimal gland hypersecretion
ROA of h1ra
po, ophthalmic, intranasal
CI of H1RA
urinary retention
increase IOP
hyperthyroidism
CV disease
side effects of H1RA
sedation (older histamines)
Drowsiness
anticholinergic effects
n&v
loss of appetite
epigastric distress
drug interaction of H1RA
cns depressant drugs (sedative drugs, alcohol)
when to take H1RA
- take approximately 1-2 hrs before anticipated exposure to allergen
- take with meals or with full glass of water
can u use more than one antihistamine at a time? why?
no. can lead to tolerance
what is the appropriate drug therapy when tolerance to h1ra develops
change to an agent in a different chemical class
first gen Antihistamines are (3)
nonselective
sedating
more lipid soluble
swcond gen Antihistamines are (3)
peripherally selective
nonsedating
little or no cns effects
1st gen h1ra classes
alkylamine class
ethanolamine
phenothiazine
piperidine
1st gen h1ra alkylamine class drugs
brompheniramine maleate
chlorpheniramine maleate
dexchlorpheniramine maleate
1st gen h1ra ethanolamjne class
carbinoxamine maleate
clemastine fumarate
diphenhydramine hydrochloride
1st gen h1ra phenothiazine class
promethazine hydrochloride
1st ge h1ra piperidine class
cyproheptadine hcl
antihistamine drug for those with insomnia but can cause constipation
diphenhydramine (benadryl)
2nd gen h1ra drug classes
phthalizinone class
piperazine class
piperidine class
2nd gen h1ra phthalizinone class
azelastine (Nasal only)
bepotastine (ophthalmic only)
2nd gen h1ra piperazne class
cetirizine
levocetirizine
2nd gen h1ra piperidine class
desloratadine
fexofenadine
loratadine
olopatadine (Nasal only)
sympathomimetic agents thay act on adrenergic receptorsnin the Nasal mucosa causing vasoconstriction and improve ventilation
decongestants
decongestants that has little or no systemic absorption but with higher local effects
topical decongestants
sideffect of topical decongestants when used for more than 3 to 5 days
rhinitis medicamentosa or rebound vasodilation with congestion
short acting topical decongestant
phenylephrine hydrochloride (doa 4hrs)
intermediate acting topical decongestants
naphazoline hcl (doa 2-6hrs)
tetrahydrozoline hcl
long acting topical decongestant
oxymetazoline hcl (doa 12hrs)
xylometazoline hcl
pros of using systemic decongestants
lasts longer and has less irritation
doesnt cause rhinitis medicamentosa
drug that replaced pseudoephedrine in many non prescription antihistamine decongestant combination
phenylephrine
side effects of systemic decongestants
mild cns stimulation
stroke (higher doses)
contraindications of systemic decongestants
Hypertension (esp MAOIw)
excellent choice for treating perennial rhinitis and can be useful in seasonal rhinitis, especially if begun in advance symptoms
Nasal steroids
Nasal steroids are effective with minimal _____ effects
adverse
most effective for the treatment of allergic rhinitis
nasal steroids
nasal steroids reduce inflamm by:
reducing mediator release
suppressing neutrophil chemotaxis
reducing intracellular edema
causing mild vasoconstriction
inhibits cell-mediatws late-phase reaction
nasal steroids drugs
beclomethasone
budesonide
flunisonide
fluticasone
mometasone
CI of Nasal steroids
patients with Nasal septum ulcer
with recent Nasal surgery or trauma
in using Nasal steroids, peak responses may not be observed for 2 to 3 weeks. when a response is achieved, the dosage may be (reduced or increased)
reduced
can u use Nasal steroids when u have congestion?
no.
blocked Nasal passages should be cleared with a decongestant or saline irrigation before administration
in using Nasal steroids, avoid ____ or blowong their noses for at least ______ minutes after administration
sneezing
10 min
mast cells stavilizers are only used as?
prophylaxis
mast cells stabilizer drug
cromolyn sodium (Nasal spray)
prevents antigen-triggered mast cell degranulatjon and release of mediators of allergic reaction through blockade of calcium influx into the mast cells
mast cells stabilizer
can u use mast cell stabilizers when u have congestion
no. use decongestants first
dosing of cromolyn sodium to 2 yr old
1 spray in each nostril 3-4x at regular intervals
when should u use mast cell stabilizers in seasonal rhinitis
initiate just before the start if the offending allergens season and continue throughout the season
when should u use mast cell stabilizers for perennial rhinitis
di ko rin alam eh HAHA
effects may not be seen for 2 to 3 weeks
Antihistamines or decongestants may be needed during thisninitial phase of therapy
exhibits antisecretory properties when applied locally
anticholinergics
anticholinergics provides symptomatic relief of ___
rhinorrhea
ipratropium bromide dosing
2 sprays (42 mcg) 2-3x daily
montelukast inhibts what receptor whoch causes the prevention of the releasenof mediators from the mast cells
cysteinyl leukotriene receptor
when should montelukast be administered if px has combined asthma and seasonal allergic rhinitis
in the evening
Dose of montelukast for
adults
children 6-14 yo
2-5 yo
adults >15 yo: 10mg tab od
6-14 yo: 5mg chewable tab
2-5 yo: 4mg chewable tab or Oral granule packet od
