Term
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Definition
an immune mediated response facilitated by IgE antibodies on mast cells in the nasal mucosa that interact with SPECIFIC ALLERGEN TRIGGERS
the nose acts like a filtration system. it heats, humidifies, and cleans inhaled air so it can be used in the lungs
allergic rhinitis primarily develops from the cleaning component of this filtration system
this aspect uses nasal cilia to move trapped foreign particles posteriorly so that they can be eventually swallowed and eliminated in the GI tract
epithelium - nasal mucosa that traps the antigen (i.e. allergic trigger)
antigen - allergic trigger. in patients with a genetic predisposition for a specific allergic trigger, an immune mediated response will cause allergic rhinitis symptoms
APC (antigen presenting cell) - after allergen sensitization, IgE specific antibodies are bound to mast cells; re-exposure of the antigen will interact with these IgE specific antibodies and will cause degranulation and release inflammatory mediators from the mast cells; a very rapid, symptomatic allergic response is experienced with re-exposure of the antigen
the allergic response seen in patients with allergic rhinitis is often categorized by immediate and late phase allergic reaction |
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Term
| acute phase allergic reaction |
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Definition
pathophysiology:
onset - seconds to minutes
allergen exposure -> produce IgE antibodies (antigen specific) -> attach to nasal mast cells and basophils -> degranulation of mast cells -> release of histamine, leukotrienes, prostaglandins, tryptase, kinins, cytokines
symptoms:
SNEEZING, RHINORRHEA, POSTNASAL DRIP, PRURITUS (EYES, THROAT EARS) |
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Term
| late phase allergic reaction |
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Definition
pathophysiology:
4-24 hours later
caused by cytokine release of mast and T helper cells
migration and activation of inflammatory cells (eosinophils, neutrophils, macrophages, basophils) in nasal mucosa
"hyper-responsive" state - lower amounts of allergen will induce an allergic response AND more sensitive to non-allergic irritants (car exhaust, perfumes, tobacco smoke)
symptoms:
NASAL CONGESTION |
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Term
| prophylactic measures for patients with allergic rhinitis |
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Definition
identification and avoidance of triggers is a primary part of both treatment and preventative plans in patients that have allergic rhinitis
general approaches to allergic rhinitis triggers:
environmental modifications
pollens:
keep windows and doors closed during pollen season
avoid fans that draw in outside air
use air conditioning
if possible, eliminate outside activities during times of high pollen counts
shower, shampoo, and change clothes following outdoor activities
use a vented dryer rather than an outside clothesline
molds:
use similar controls as above
avoid walking through uncut fields, working with compost or dry soil, and raking leaves
clean indoor moldy surfaces
fix all water leaks in home
reduce indoor humidity to < 50% if possible
house dust mites:
encase mattress, pillow, and box springs in an allergen impermeable cover
wash bedding in hot water weekly
remove stuffed toys from bedroom
minimize carpet use and upholstered furniture
reduce indoor humidity to < 50% if possible
animal allergens (if removal of pet is not acceptable):
keep pet out of patient's bedroom
isolate pet from carpet and upholstered furniture
wash pet weekly
cockroaches:
keep food and garbage in tightly closed containers
take out garbage regularly
clean up dirty dishes promptly
use roach traps
other recommendations:
do not allow smoking around the patient, in the patient's house or in the family car
minimize the use of wood burning stoves and fireplaces
HEPA (high efficiency particulate air) filters are only effective for removing light weight airborne particulates. depending on the specific causative allergen, these expensive filtration systems may not be worth the overall cost |
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Term
| prophylactic use of medication therapy |
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Definition
antihistamines
decongestants
intranasal corticosteroids
start prior to allergen exposure
should start 1-2 weeks before the onset of that season |
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Term
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Definition
| block effects of histamine by competing for histamine receptors (inhibit effects of H1 receptors) |
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Term
| antihistamines place in therapy |
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Definition
1st line agents for active symptoms or prevention of symptoms
due to higher sedation with non-selective oral agents, peripherally selective oral agents are often used first line
these medications are much more effective at PREVENTING HISTAMINE MEDICATED EFFECTS (do not work well at reversing actions of histamine)
primarily controls allergic rhinitis symptoms of: early phase allergic reaction - rhinitis, itchy eyes/throat/nose, watery eyes, post nasal drip; NOT good for head congestion
intranasal antihistamines:
rapid onset
reduce nasal congestions
less effective than nasal steroids
used in conjunction with antihistamine OR nasal steroid OR alone
PRECAUTIONS:
these medications should be used cautiously in patients with - BPH, concurrent use of other anticholinergic medications, older men, increased intraocular pressure, hyperthyroidism, cardiovascular disease |
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Term
| antihisatmines: patient education |
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Definition
when first starting to use medication, be cautious of drowsiness. avoid any activities requiring focus or concentration (ex. driving motor vehicle) or that may exacerbate this ADR (ex. alcohol)
may need to consume more water as these medications can cause constipation, dry mouth, and other anticholinergic (drying) problems
only use 1 type of antihistamine in a day
read labels of OTC product and consult a health care professional prior to use. many OTC products contain medications similar to these products |
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Term
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Definition
PO agents: pseudoephedrine (Sudafed), phenylephrine (Sudafed PE)
intranasal agents: naphazoline (Naphcon), tetrahydrozoline (Tyzine), oxymetazoline (Afrin)
DO NOT USE INTRANASAL DECONGESTANTS FOR MORE THAN 3 CONSECUTIVE DAYS
may cause rebound congestion "rhinitis medicamentosa" with prolonged use |
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Term
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Definition
| stimulate alpha adrenergic receptors in vascular smooth muscle of nose; nasal mucosal capillary vasoconstriction; nasal congestion relief |
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Term
| decongestants: place in therapy |
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Definition
1st line agents for active allergic rhinitis symptoms
primarily controls allergic rhinitis symptoms of late phase (congestion) |
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Term
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Definition
burning, stinging, dryness of nasal cavity, sneezing
CNS stimulation (insomnia, jitteriness), tachycardia, urinary retension
caution use: HTN, glaucoma, BPH, arrhythmias, diabetes, hepatic/renal impairment, hyperthyroidism
decongestants + MAOIs = HYPERTENSIVE CRISIS! |
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Term
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Definition
beclomethasone (Beconase AQ)
budesonide (Rhinocort AQ)
flunisolide (Nasarel)
fluticasone (Flonase, Veramyst)
mometasone (Nasonex)
triamcinolone (Nasocort AQ)
ciclesonide (Omnaris) |
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Term
| inhaled corticosteroids: MOA |
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Definition
| suppress neutrophil chemotaxis, reduce inflammatory medator release, decrease mucosal edema, inhibit mast cell medicated late phase reactions, mild vasoconstrictive properties |
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Term
| inhaled corticosteroids: place in therapy |
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Definition
most agents approved for use in 6 years of age and older (fluticasone has an indication for 4 yo and older)
clinically used as 1st or 2nd line agents for active or prevention of allergic rhinitis symptoms
primarily controls allergic rhinitis symptoms by inhibiting both early and late phase reactions: decrease microvascular permeability, edema, and mucus secretion
WILL NOT PROVIDE IMMEDIATE RELIEF OF SYMPTOMS
best option for patient with head congestion and for patients with year round persistent problems; can be used in patients with seasonal allergic rhinitis but they should start it 1-2 weeks before the onset of that season
aqueous = "drier" nose and predominant NASAL CONGESTION
1. fluticasone (Flonase), beclomethasone dipropionate (Qvar), triamcinolone (Tri-Nasal)
2. less local irritation with aqueous formulations
nonaqueous = "wet" nose and predominant RHINORRHEA
beclomethasone (Beconase), budesonide (Entocort), triamcinolone acetonide (Nasocort AQ) |
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Term
| inhaled corticosteroids: ADRs |
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Definition
| HA, stinging, sneezing, epistasis |
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Term
| inhaled corticosteroids: patient education |
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Definition
when first starting to use medication, initial response may be seen in 3-5 days but full benefits may not be experienced until 2-3 weeks of daily use
avoid sneezing or blowing nose for at least 10 minutes after use |
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Term
| non selective (1st generation) antihistamines ADRs |
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Definition
diphenhydramine (Benadryl)
HIGH sedative effects
HIGH anticholinergic effect
chlorpheniramine (Ahist, Aller-Chlor, ChlorHist, Chlorphen)
LOW sedative effects
MODERATE anticholinergic effects
clemastine (Dayhist, Tavist)
MODERATE sedative effects
HIGH anticholinergic effects
brompheniramine (BPM, BromSpiro, Brovex, Lodrane, LoHist, Resp-BR, LaZol)
LOW sedative effects
MODERATE anticholinergic effects
common ADRs:
cross BBB = sedation, drowsiness, dizziness, confusion
anticholinergic properties due to binding to muscarinic receptors
avoid in: elderly, urinary incontinence (urinary retention), taking other agents with high anticholinergic properties |
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Term
| peripherally selective (2nd generation) antihistamines ADRs |
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Definition
loratadine (Alavert, Claratin)
LOW sedative effects
LOW to NONE anticholinergic effects
cetirizine (Zyrtec)
LOW to MODERATE sedative effects
LOW to NONE anticholinergic effects
fexofenadine (Allegra)
LOW sedative effects
LOW to NONE anticholinergic effects
levocetirizine (Xyzal)
LOW to MODERATE sedative effects
LOW to NONE anticholinergic effects
desloratidine (Clarines)
LOW sedative effects
LOW to NONE anticholinergic effects
comments:
sedation: low (do not readily cross the BBB)
drying: low (do not bind to muscarinic cholinergic receptors
other - GI, loss of appetite = class effect |
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Term
| intranasal antihistamines ADRs |
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Definition
azelastine (Astelin, Astepro)
olopatadine (Pataday)
both can cause drowsiness - intranasal products can cause significant drowsiness (40% systemic absorption
headache, drying effects, sedation, local irritation, and diminished effects over time are also common ADRs reported with these products |
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Term
| allergic rhinitis in children |
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Definition
oral antihistamines: cetirizine 2 yo and older
nasla cromoyln
nasal corticosteroids (>4 yo for use) |
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Term
| allergic rhinitis treatment for pregnancy |
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Definition
saline nasal spray = MOST PREFERRED
oral antihistamines - chlorpheniramine preferred
nasal cromolyn - intranasal steroids may be used only if not adequately effective
avoid oral decongestants during 1st trimester - abdominal wall defects to fetus |
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