chronic inflammatory disease of airways; predominantly disease of inflammation w/ superimposed bronchospasm causing reversible airway obstruction; all triggers produce same response in airways - constrictin of smooth muscle of airway, inflammation & edema of bronchial mucosa & increased productin of bronchial mucus

so, wheezing on exhalation 

drugs that reverse airway constriction (bronchi & bronchioles)

relax smooth muscles of the bronchial tree to reverse bronchospasm; this allows an increase in lumen of the bronchioles & alveolar ducts and a decrease in resistance to air flow

do not alter the underlying inflammatory process; used only for sympomatic relief of BRONCHIAL CONSTRICTION in conditions such as asthma, bronchitis, COPD

beta-adrenergic agonists

methylxanthines

muscarinic-receptor antagonists (anticholinergics) 

adrenergic agents mimicking effects of sympathetic NS stimulation

catecholamines that stimulate adrenergic receptors directly, thereby stimulating cells that respond to morepinephrine and epinephrine and causing a sympathetic response: increased HR & force of cardiac contraction, vasoconstriction, bronchodilation, decreased gastric mobility, etc. 

produce bronchodilation by stimulating cAMP production; cAMP is believed to be a bronchodilator

inhibit release of mast cell mediators

decrease vascular permiability

increase mucociliary clearance

affect both B1and B2 receptors & A1 receptors

cause bronchodilation (from B2 stim.), cardiac stimulation (tachycardia & cardiac arrhythmias from B1 stim.), and vasoconstriction/elevation in BP (from A1 stim.) 

Epinephrine

Ephedrine (generic)

Isoproterenol (affects B1 & B2 receptors; no affiity w/ A receptors) 

they are potent, short-acting w/ almost immediate onset of action (< 1 min) & short duration of action (1-3 hrs)

effective for acute symptoms in the early phase; nave no effect in the late phase of asthma

pts who have frequent asthma exacerbations may overuse their inhaler, leading to systemic absorption sufficient to cause cardiac arrhythmias, hypertension,anxiety attacks, insomnia 

b/c of their nonselective actions, side effects, and tolerance develop't, inhaled forms of these drugs are seldom used in the ambulatory/impatient settings 

sub-cutaneously

inhaled  

have a relatively slow onset of action & prolonged effect

not recommended for tx of acute bronchospasm b/c not a "quick-relief"/"rescue" medication

pts should use a short-acting B agonist PRN to control acute symptoms

BID dosing (12hrs/dose) to keep dilated all the time 

maintenance tx in asthmatics requiring scheduled B agonist (moderate to severe asthma, adjunct to anti-inflammatory agents)

prodominance of nocturnal symptoms

prevention of exercise-induced asthma (EIA)

allergen- & histamine-caused bronchospasm 

common long-acting beta 2 agonist:

salmeterol (Serevent) 

common long-acting beta 2 agonist:

formeterol (Foradil) 

relatively B2 agonist-selective in their action & produce more bronchodilation w/ fewer cardio. effects

tachycardia, palpitations, tremor & paradoxical bronchospasm can occur

high doses can cause hypokalemia

caution in pts w/ uncontrolled cardio disorders & convulsive disorders 

caution in CHF, HTN, liver disease, elderly

caution in DM, glaucoma (they can increase blood glucose & intraocular pressure)

contraindicated in pts w/ hyperthyroidism & uncontrolled arrhythmias

Beta adrenergic blocking agents antagonize the effects of adrenergic agonists

Bronchodilator:

Methylxanthines 

Aminophylline is the only form that can be administered IV

diferent preparations are not bioequivalent 

prophylaxis & tx of chronic asthma

tx of bronchospasm r/t chornic bronchitis & emphysema (COPD)

used less frequently than in the past b/c more effective and safer meds are now available 

hyperthyroidism & uncontrolled arrhythmias

caution in CHF, HTN, liver disease, seizure disorders, elderly

there is no antidote for xanthine, standard aid measures (charcoal, emesis, gastric levage) must be used for toxicity

Bronchodilator:

Muscarinic-receptor antagonists (anticholinergics) 

onset 5-15 min; peak 1-2 hrs; duration 4-6 hrs

minimal systemic absorption (very safe)

infrequent

systemic side effects are minimal

most common: cough, dry mouth, headaches 

hypersensitivity

no drug interactions 

w/ the recognition that asthma is an inflammatory process, much progress has been made in the development & use of anti-inflammatory therapy

while these therapies are relatively ineffective in treating acute attacks, they do reduce frequency & severity 

Glucocorticosteroids

Mast cell stabilizing agents

Leukotriene Antagonists 

Anti-inflammatory agent:

Glucocorticosteroids 

no significant drug interactions

no significant contraindications

contraindicated in the primary tx of status asthmaticus (b/c/ not immediate onset) 

fluticasone (Flovent)

ADVAIR DISCUS: (fluticasone + salmeterol)

• combined glucocortico. & B agonist
• use for long-term control 

teach pt. to correctly use MDI/nasal inhaler

teach pt to use a spacer w/ MDIs so med doesn't end up in the lungs 

Anti-inflammatory agent:

Leukotriene Modifiers (antagonists) 

HAs, dyspepsia (heartburn)

drug allergy

liver disease (not in montelukast) 

hypersensitivity

approved for kids 2 yrs + (kids chewables shouldn't be swallowed whole) 

Anti-inflammatory agent:

Mast Cell Stabilizer 

cromolyn sodium (Intal)

excellent; available as metered nasal spray, capsules for inhalation, nebulization solution, aerosol & oral form 

runny nose, sneezing, nasal congestion, headache, itching of the nose/eyes/throat

IgE-mediated allergic response to one or more airborne allergens

multiple risk factors, most common is family history:

• both parents atopic: 50% risk of atopy in child
• one parent/sibling: 29%
• neither parent is atopic: 13% 

Pt education

allergen avoidance

pharmacotherapy

allergen-specific immunotherapy 

tx of allergic rhinitis:

Pharmacotherapy 

topical intranasal corticoids are the first step

fluticasone (Flonase)

mometasone (Nasonex) 

Classification of antihistamines/H1-receptor antagonists:

1st & 2nd generation 

diphenhydramine (Benedryl)

loratadine (Claritin) 

in use w/ MAO inhibitors, narrow-angle glaucoma, peptic ulcer, prostatic hypertrophy

caution in elderly - excessive sedation

not recommended w/ bronchitis/pneumonia: dry secretions making them more difficult to remove

antihistamines taken by young kids can cause drowsiness w/ first few administrations & paradoxic excitement (CNS excitation) w/ repeated use

anticholinergics, MAOIs, tricyclic antidepressants: increased severity of anticholinergic side effects (e.g. dry mouth, blurred vision, urinary rention)

ETOH: increased sedation 

excitation of the central NS (leading to insomia, restlessness, agitation), tachycardia, urinary retention & increase in BP; rebound congestion

should be avoided in HTN, DM, hyperthyroidism, CAD, or urinary obstructive disease 

Antitussives 

only when the cough is so severe that it causes excessive fatigue & interrupts sleep

should only be used to inhibit frequency of dry, nonproductive cough that keeps pts awake

should not be used if the cough is productive (secretions can pool & cause pneumonia) 

Classification of antitussives:

opioid agents & nonopioid agents 

used to facilitate expectoration; facilitate the secretion of fluid in the resp. tract, thus liquifying secretions and allowing for easier expectoration during a cough; this increase in flow lubricates the airway & may relieve the cough

these agnest also decrease the viscosity of mucus, making removal easier 

use w/ caution in clients w/ fever or severe persistent cough

preps that contain ETOH can cause severe symptoms in pts taking disulfiram 

WATER IS BEST

encourage fluid intake of 2000 ml/day

follow each dose of quaifenesin w/ a full glass of water 

agents reacting directly w/ mucus to make it thinner & more easily expectorated

used to promote mucus clearing in: pneumonia, bronchitis, COPD, TB, diagnositic procedures to obtain a mucus specimen

used to treat acetaminophen (Tylenol) overdose