Allergic rhinitis Flashcards
risk factors of allergic rhinitis
age - adolescents and young adults
family history
repeated exposure to multiple offending allergen
presence of other allergic conditions (asthma and atopic dermatitis)
pathophysiology
IgE produces after first contact and binds to mast cells and basophils
second exposure IgE recognizes allergen causing degranulation and release of preformed mediators, lasts 30-90 min
4-8 hours later get migration of inflammatory mediators, eosinophils etc and congestion predominated
nasal symptoms
paroxysmal sneezing
itching
watery rhinorrhea
nasal congestion
what happens after persistant inflammation
decrease threshold of allergen needed to produce a response
ocular symptoms
red irritated eyes itching or burning tearing stringy watery discharge puff eyelid in the morning
facial symptoms
openmouth breathing
allergic salute
darkeningunder eyes due to venous congestion
wrinklens beneath the lower lid
systemic symptoms
cognitive impairment
fatigue
irritability
malaise
3 characteristic exposure time to allergens
seasonal
perennial (all year)
episodic
2 characterizations of symptom frequency
intermittent is = 4 days per week OR = 4 weeks per year
persistent is >4days per week AND >4 weeks per year
mild symptom severity
doesnt interfere with quality of life
no troublesome symptoms
moderate to severe symptom severity
symptoms interfere with the quality of life
abnormal sleep, impairment of activites, troublesome symptoms
differential diagnosis of allergic rhinitis
infectious rhinitis (cold) idiopathic or inflammatory non allergic rhinitis vasomotor rhinitis (non inflammatory) hormonal - pregnancy, mensus nasal polyps drug induced rhinitis occupational rhinitis
describe vasomotor rhinitis
non allergic
occurs later in life
nasal congestion, rhinorrhea, postnasla drip usually in women 40-60
many different triggers
medications that can cause non allergic drug induced rhinitis
antihypertensive agents oral contraceptives NSAIDS topical decongestants overuse older antipsychotics
red flags
under 2 (asthma?) wheezing shortness of breath tightness in chest painful ears/sinuses (infection?) fever purulent nasal/ocular discharge allergen not identifiable no response to OTC after 2 weeks
how does normal saline help with allergic rhinitis
reduce concentration of inflammatory mediators
flush out mucus and allergens
improve nasal airflow
how might nasal breathing strips help
mechanical means to improve nasal airflow
relieve symptoms?
goals of therapy
avoid or minimize the exposure to the allergen
alleviate symptoms
minimize adverse effects of the medication
antihistamine mechanism of action
reversible antagonist at H1 receptor preventing binding and action at the receptor site
which symptoms do antihistamines help with
reduce sneezing, runny nose, and itching but not congestion or stuffiness (except desloratadine, cetirizine, fexofenadine)
2 examples of first generation antihistamines
chlorpheniramine
diphenhydramine
examples of second generation AH
loratadine
cetirizine
fexofenadine
side effects of first gen
dry mouth and eyes constipation urinary retention sedation fatigue dizziness sedation mucus secretion thickened
drug interactions with first gen
alcohol
hypnotics
sedatives
CNS depressants
average dosing and onset for 2nd gen
about an hour
dose once daily
side effects of second gen
headache
cetirizine may cause drowsiness
how should AH be taken for chronic allergic rhinitis
start 2 weeks before season and continue throughout the season and 2 weeks after
taken on a daily basis
how should AH be taken for infrequent exposure
2-4 hours before exposure
how to take AH if already experiencing symptoms
wont work right away because no effect on the histamine already released can start but will only see the benefit in 2-3 days
what may be some causes of ineffectiveness of AH
non adherence increased antigen exposure worsening of condition severe diseae similar symptoms to unrelated disease switch to another class of AH
contraindications for 1st gen
glaucoma (increases pressure) bladder obstruction peptic ulcer hyperthyroidism (increase cardiac effects) cardiac disease prostate disease chronic lung disease (thickened mucus)
oral decongestants
phenyephrine
pseudoephedrine
intranasal decongestants
oxymetazoline
xylometazoline
phenylephrine
decongestants mechanism of action and what it treats
vasoconstriction on the alpha receptors in nasal mucosa and decreased inflammation only useful in late stage to help with congestion
onset of action for oral decongestants
15-30 min
age for oral decongestants
over 6
adverse effects of aroal decongestants
dizzy headache tremor difficulty sleeping peripheral vasoconstriction tachycardia palpitation blood sugar
contraindications of oral decongestants
heart disease gluacima diabetes hyperthyroidism porstate enlargment severe hypertension
onset for intranasal decongestants
5-10min
side effects of intranasal decongestants side effects
nasal burning stinging dryness
nucosal ulceration
what is rhinitis medicamentosa in intranasal decongestants
rebound congestion that occurs from prolonged use (3-5days) that causes down regulation of alpha receptors
rebound swelling of nasal mucosa
what age can use intranasal decongestants
over 12
which decongestant is best to use
topical because less systemic effects
what are some alternates to decongestants
desloratidine
cetirizine
fexofenadine
normal saline
opthalmic decongestant mechanism of action
vasoconstriction decreases eye redness
contraindications of opthalmic decongestant
glaucoma
side ffects of opthalmic decongestants
burning, stinging
rebound redness and swelling if used more than 10 days
example of mast cell stabolizer
sodium cromoglycate
mast cell stabilizer mechanism of action
inhibits degranulation of mast cells to alleviate runny nose itching and sneezing
disadvantages to mast cell stabilizers
delayed onset
may take 4-7 days for any improvement and full benefit 3-4 weeks
requires 3-4 times a day dosing so lack of adherence
not very effective
intranasal corticosteroids mechanism of action
decrease influx of inflammatory cells and inhibit release of cytokine which leads to the reduction of inflammation
onset of intranasal corticosteroids
30 min max effect takes 7-14 days
side effects of intranasal corticosteroids
burning stinging bosebleeds headache throat irritation nos sytemic effects because quickly metabolized
age you can use intranasal corticosteroids
triamcinolone over 12
fluticasone over 18
what can pharmacists prescribe for vasomotor and allergic rhinitis
corticosteroid nasal preparations for topical use
why is it better to use 2nd gen AH than intranasal AH
have similar efficacy but lots of side effects and twice daily dosing
what prescription combo is available and when do you use it
intranasal corticosteroid and antihistamine
only when no resolution with INS alone
example of prescription intranasal anticholinergic and how does it work
ipratropium solution prevents secretions of the nasal mucosa
when to use IN anticholinergics
excessive rhinorrhea
somet ypes of vasomotor rhinitis
why is there no drug interactions with IN anticholinergic
no systemic absorption and doesnt cross BB
when can you use oral steroids
for short time in patients with severe symptoms, in combo with INS
what do you use for persistant symptoms that affect the quality of life
intranasal corticosteroids
what do you use for mild intermittent symptoms
oral second gen antihistamine
what is immunotherapy
giving the patient some of the allergen so the immune system would not respond when exposed to the allergen
two types of immunotherapy
subcutaneous injection - regular intervals at doctors office
sublingual - first at office then at home
best option for children?
INS can be prescribed for children over 4 but likely use 2nd gen antihistamine because 1st cause hyperactivity
nasal saline before eating and sleeping
treatment of allergic rhinitis in pregnant women (if first time experiencing symptoms prob vasomotor not allergic!!)
loratidine and cetirizine
what reduces effectiveness of fexofenadine
juices
monitoring of allergic rhinitis
symptom relief within 3-4 days
complete relief may take 2 weeks of not refer
pharmacist follow up in a week
