(10) Allergy and Asthma

How is allergic rhinits linked to asthma?

Allergic rhinitis can lead to exacerbation of asthma - symptoms can trigger asthmatic response.

What are adverse effects of nasal decongestants?

Cardiovascular stimulation, CNS stimulation, may exacerbate HTN, DM, CHD, BPH, hyperthroidism, intraocular pressure. Topical decongestants may cause bruning, stinging, sneezing, local dryness; rhinitis medicamentosa (rebound congestion: should only use topical decongestants for 3-5 days)

What are the treatment goals for allergic rhinits? What are some therapy modes?

Reduce symptoms and improve quality of life through individualized therapy for symptom relief and control: Non-pharm therapies, pharmacologic therapies, immunotherapies

What are the pseudoephedrine sales limitations per patient? What other tracking methods are required for pseudoephedrine sale?

3.6 g/day; 9 g/month. Requires secure holding of pseudo, record keeping, and valid ID (18 or older)

When is it appropriate to self-treat for asthma?

A diagnosis of intermittent asthma by an MD; current symptoms normal for PT, are mild, intermittent, and short duratio.

What class of antihistamines has a highher risk of paradoxical CNS stimulation and what are some medications in this class?

Alkylamines: brompheniramine, chlorpheniramine, dexbropheniramine, triprolidine, pheniramine

Compare and contrast signs and symptoms of allergic rhinits and nonallergic rhinits

Allergic rhinits has bilateral symptom presentation that improves during the day and worsens at night and upon awakening; frequent sneezing, watery anterior rhinorrhea, frequent pruritius of eyes, nose, and/or palate; variable nasal obstruction; frequent conjunctivitis; sinus pain from congestion and throat pain from post-nasal drip; rare anosmia, and rare epistaxis; facial features of allergic shiners, Dennie's lines, allergic salute, allergic crease, allergic gape. Nonallergic rhinitis has unilateral or bilateral presentation that is constant day and night; little or no sneezing; posterior watery or thrick and mucopurulent rhinorrea; no pruritus but with severe nasal obstruction; pain can be variable, with frequent anosmia and recurrent epistaxis. Facial features include nasal polyps, nasal septal deviation, enlarged tonsil and/or adenoids.

What is the primary pharmacologic therapy for allergic rhinits? What is the MOA of these drugs?

Anithistamines: compete with histamine-1 receptor sites, preventing histamine-receptor activation, preventing mediator release.

What are three pharmacologic self-care therapies for asthma?

Asthmanefrin (racepinephrine inhalation solution); Primatene tablets (ephedrine/guaifenesin); Bronkaid tablets (ephedrine/guaifenesin)

What are the types of adverse effects associated with antihistamines?

CNS effects: depression (sedation, impaired performance) and stimulation (anxiety, hallucinations); paradoxical excitation in young children and elderly. Anticholinergic effects: anti-SLUDGE. Caution in asthamtics - drying secretions can cause bronchospasms. Avoid in COPD, enlarged prosate, and narrow-angle glaucoma. May also cause sunlight sensitivity.

What is important to note about cetirizine (relative potency and side effect)?

Cetirizine (zyrtec) is shown to be more potent than loratidine (Claritin) or fexofenadine (Allerga), but causes more sedation.

What are exclusions for self-treatment for allergic rhinitis?

Children < 12 years old; pregnant or lactating women; symptoms of non-allergic rhinits; symptoms of otitis media, sinusitis, bronchitis, other infections; symptoms of uncontrolled asthma; severe persistent allergic rhinitis unresponsive to treatment; severe or unacceptable side effects of treatment.

How long do symptoms of allergic rhinits last?

Chronic symptoms may last year round. Seasonal symptoms may last from Feb - Oct due to exposure

What are some common environmental, chemical, or condition-basd triggers for asthma?

Environmental: cold air, dust mites, cockroaches, dander, irritants, mold/fungi, tbx, pollen. Drugs/chemicals: Beta blockers, Aspirin, NSAIDs, preservatives, seafood/shellfish, occupational irritant exposure, perfumes. Conditions: GERD, allergic rhinits, panic attacks, pregnancy, stress/excitement, viral respiratory infections

What is the general pathophysiology of asthma?

Exposure to trigger --> degranulation of mast cells --> release of histamine and leukotrienes --> bronchoconstriction

What are some risk factors associated with asthma?

Family history; concurrent allergic disease; smoking/exposure 2nd-hand smoke; high BMI; viral respiratory infection during first 3 years of life

How do antihistamines differ by generation? Which type of antihistamine is recommended by the WHO?

First generation: non-selective (central and peripheral) and sedating. Second genreation: peripherally selective, and non-sedating. WHO recommends non-sedating antihistamines.

What is an important DDI with fexofendaine?

Fruit juices: grapefruit, apple, orange: decreases absorption by inhibting intestinal OATP. Should separate by 2 hours.

What are some allergens to avoid and how can that serve as non-pharm therapy?

House-dust mites: can be removed by decreasing household humidity < 50%, removing carpets, upholstery, curtains (use blinds instead). Wash bedding at least weekly in hot water (130 F, 54.4 C). Outdoor mold spores: avoid decaying plant material. Indoor mold: avoid houseplansts, reduce humidity, clean humidifier. Animals produce pet dander - remove animal from PT room, or vacuum with HEPA filter cleaner, and wash hands after petting. Cockroaches: lower humidity, clean dishes and foodstuffs, remove trash. Secondhand smoke; Tree pollen: avoid outdoor activies from 5-10am; weed pollen (mid aug-oct); Grass pollen (late spring to summer) - AC instead of opening windows.

What are some important administration considerations for using a neti pot?

Increased risk of infections with tap water: can only use distilled or filtered water, or water boiled for 3-5 min and then cooled. Use mixture within 24 hours of sterilizing. Rinse and air dry irrigation device between use.

What is the DOC for pegnancy and lactation for treatment of allergic rhinits?

Intranasal cromolyn (category B). Alternatively, loratadine, cetirizine, chlorpheniramine.

What is the first choice treatment of allergic rhinits for children < 12 years of age per PCP recommendations?

Loratidine: Claritin syrup and chewable > 2 y/o, RediTabs > 6 y/o. Alternatively can use fexofenadine or cetirizine. Both children and the elderly are particularly susceptible to paradoxical excitation.

Which pharmacologic therapy for allergic rhinits can be used as prophylaxis?

Mast cell stabilizers (e.g. Chromoyn sodium): use 3-7 days before initial effects, use 2-4 weeks continuously for maximum therapeutic effects. Can be used in patients older than 5 with minimum ADRs

What are four types (brand and generic) of nasal decongestants?

Naphazoline (privine), Oxymetazoline (Afrin), Phenylephrine (Neo-Synephrine), Xylometazolone (Otrivine)

What are three complications of chronic rhinits?

Nasal polyps (larger polyps that can cause obstruction and blockage of drainage), sleep anpea, hyposmia

What is the first intranasal steroid to be approved for OTC use?

Nasocort (approved 10/13) for treatment of allergic rhinits symptoms in children > 2 years. Control of symptoms after 1 week (if no relief, refer). Another recent approval is for Flonase

What are exclusions to self-treatment for asthma?

No previous diagnosis of asthma by PCP; persistent asthma; severe symptoms/different symptoms; ER visit/hospitalization; using rescue inhaler > 2x week; HF, COPD, vocal cord injury; Sx of resp. infection; taking asthma control meds; has not seen PCP in the last year; pregnant or < 5 y/o

What is the MOA of racepinephrine and ephedrine? When can these be used?

Nonselective beta-agonist with activity on alpha receptors: generally indicated to treat mild, infrequent symptoms. REQUIRED: diagnosis

List some common allergens and their locations:

Outdoors: pollen, mold, pollutants. Indoor: House-dust mites, cockroaches, mold spores, cigarette smoke, pet dander; Occupational: wool dust, latex, resin, biologic enzymes, organic dusts (flour)

What class of antihistamines are non-sedating and what are three medications in this class?

Piperidines: fexofenadine, loratadine, phenidamine.

What are two acute complications of allergic rhinits?

Sinusitis and otitis media with effusion

What is the most important step in the management of asthma?

Prevention: avoiding triggers, getting vaccinated for flu, using antihistamines, and adherence to long-term meds

What is an option for immunotherapy in the treamtent of moderate to severe allergic rhinits?

SC injections of gradually increasing doses of allergens (or sublingual) -- most effective for pollen-related allergens.

What is the process by which saline irrigation can help with allergic rhinits?

Saline irrigation flushes out mucus and irritants from the sinuses, improving air flow through the nose (promotes ciliary function of the sinuses and reduces edema by osmosis). Saline irrigation reduces histamine concentrations for up to six hours and leukotriene concentrations for up to four hours.

What are the two types of allergic rhinits?

Seasonal allergic rhinits aka "hay fever" - symptomatic from Feb - Oct. due to ragweed, grass exposure.; Perennial allergic rhinitis: chronic symptoms, often worse in the late evening from increased exposure to allegens during daytime. May last year round. Allergens of perennial rhinitis include: polluted air, dust mites, dust, cat dander, dog saliva, fungi, cosmetics, and aerosol sprays.

What is allergic rhinitis? What are some risk factors for developing rhinitis?

Seasonal allergies aka "hay fever", or perennial allergic rhinits. Risk factors include family history, elevated serum IgE, higher socioeconomic class, eczema, positive reaction to allergy skin tests

What is a precaution regarding saline irrigation?

Some experts say that chronic use of saline irrigation can remove some immune globulins in the nasal mucosa that are important for defense.

Describe the pathophysiology of allergic rhinits:

The first time the allergy-prone person runs into an allergen (e.g. ragweed), their plasma cells make large amounts of IgE, which attatch themselves to mast cells. The second time that person interacts with the allergen, the IgE-primed mast cell will release it's chemicals through degranulation: allergic symptoms.

What are five key symptoms of asthma?

Wheezing, chronic cough, chest tightness, SOB, Reversible airflow limitation: worsens with exercise, viral infections, smoke, pollen; can be worse in the early morning or nighttime.

When should a PT use a peak flow meter?

When symptoms are persistent; when PT is a poor perciever of symptoms. Refer to chart that comes with meter; always reset to zero before use and record readings. PT should stand straight, breath deeply in, seal lips tightly around mouthpiece, and blow out as quickly and forefully as possible

What is rhinits medicamentosa? What is the associated recommendation?

rhinitis medicamentosa (rebound congestion: should only use topical decongestants for 3-5 days)