Respiratory System(General Key Points)

N203ATI (Unit 8)

Respiratory System -

β2-Adrenergic Agonists

N203ATI (Unit 8)

Respiratory System -

Expected Action:Proto: albuterol (Proventil) — Others: formoterol (Foradil),

salmeterol (Serevent), terbutaline (Brethine)

• Selectively activate β2 receptors resulting in bronchodilation: bronchospasm is relieved, histamine release is inhibited, and ciliary motility is

Therapeutic Uses: • Albuterol: Inhaled, short-acting and oral, long-acting

• Formoterol, salmeterol: Inhaled, long-acting • Terbutaline: Oral, L-A

Adverse Effects: • Inhaled: Minimal adverse effects

• Oral: Tachycardia/angina d/t β1 in ♥ / tremors d/t β2 in skeletal muscle

Contraindications/Precautions: ♀ (C) • CI: tachydysrhythmias

Interactions: •

• β-blockers like propanolol negate effects of both

• TCAs and MAOIs risk of tachycardia and angina

Education: • Inhale 3-5 sec, hold 10 sec, wait 60 sec for next dose

• Use inhaled β2-agonist before using inhaled glucocorticoid

Methylxanthines

N203ATI (Unit 8)

Respiratory System -

Expected Action: Proto: Theophylline (Theolair)

• Theophylline relaxes bronchial smooth muscle bronchodilation

Therapeutic Uses: • Long-term control of asthma

Adverse Effects: • Mild toxicityGI distress & restlessness. Severe reactions

• Severe reactions can occur at therapeutic levels and include dysrhythmias and seizures. Effects unlikely @ <20 mcg/mL. Activated charcoal absorption, lidocaine for dysrhythmias and diazepam for seizures.

Contraindications/Precautions: ♀ (C) •

Interactions: • Caffeine: CNS/♥ effects of theophylline. Also [theophylline]

• Phenobarbital, phenytoin: [theophylline]

• Cimetidine, ciprofloxacin: [theophylline]

Inhaled Anticholinergics

N203ATI (Unit 8)

Respiratory System -

Expected Action: Proto: ipratropium (Atrovent) — Others: tiotropium (Spiriva)

• Block muscarinic receptors on bronchi bronchodilation

Therapeutic Uses: • Relief of bronchospasms associated with COPD

• Relief of allergen-induced and exercise-induced asthma.

Adverse Effects: • Local anticholinergic effects

Contraindications/Precautions: ♀ (B) • CI: Peanut allergy

• Caution in narrow-angle glaucoma

Education: • Usual adult dose is 2 puffs (1 minute apart)

• If taking two inhaled medications, separate by at least 5 minutes.

Glucocorticoids

N203ATI (Unit 8)

Respiratory System -

Expected Action:

Proto: beclomethasone (QVAR) — Others: budesonide (Pulmicort), fluticasone (Flovent), triamcinolone (Azmacort), prednisone (Deltasone)

• Prevent inflammation, suppress airway mucous production, and promote responsiveness of β2-receptors in bronchial tree.

Therapeutic Uses: • Inhaled: Long-term asthma prophylaxis• S-T, oral: Treat symptoms following acute asthma.• L-T, oral: Treat chronic asthma • 1º adrenocortical insufficiency• Promote lung maturity and RDS in fetuses at risk for preterm birth.

Adverse Effects: • Inhaled: Dysphasia, candidiasis, bone loss• Oral (≥10d): adrenal gland function / bone loss / hyperglycemia / glucosuria /

/ infection / peptic ulcer disease / myopathy / fluid & electrolyte disturbances.Contraindications/Precautions: ♀ (?) • CI: Live virus / systemic fungal infect.

Interactions: • Diuretics: hypokalemia • NSAIDs: GI ulceration• Glucocorticoids counteract effects of insulin and oral hypoglycemics.

Education: • Oral are for short-term use, 3-10 days following acute attack

Mast Cell Stabilizers

N203ATI (Unit 8)

Respiratory System -

Expected Action: Proto: Cromolyn (Intal) — Others: nedocromil (Tilade)

• Anti-inflammatory: Stabilize mast cells, inhibiting histamine release.• Suppress inflammatory cells (e.g. eosinophils, macrophages)

Therapeutic Uses: • Management of chronic asthma

• Prophylaxis of exercise-induced and allergen-induced asthma attacks

• Allergic rhinitis by intranasal route

Adverse Effects: • Safest of all asthma meds / safe for kids

Contraindications/Precautions: ♀ (B)

• Propellant CI: CAD, dysrhythmias, and status asthmaticus

Education: • Take 15 min before exercise

• Long-term prophylaxis may take several weeks

Leukotriene Modifiers

N203ATI (Unit 8)

Respiratory System -

Expected Action:Proto: montelukast (Singulair) — Others: zileuton (Zyflo),

zafirlukast (Accolate)

• Prevent effects of leukotrienes thus suppressing inflammation, airway edema, bronchoconstriction, and mucus production.

Therapeutic Uses: • Long-term asthma therapy in folks ≥ 12 YO

Adverse Effects:• Liver injury ĉ zileuton and zafirlukast. (nausea, anorexia,

abdominal pain)

Contraindications/Precautions: ♀ (?) •

Interactions: •

• Zileuton / zafirlukast inhibit warfarin metabolism [warfarin]

• Zileuton / zafirlukast inhibit theophylline metabolism theophylline toxicity

Education: • Zileuton given without regard to food. Zafirlukast taken ŝ food

Antitussive – Opioids

N203ATI (Unit 8)

Respiratory System -

Expected Action: Proto: codeine — Others: hydrocodone

• Suppresses cough center in the medulla oblongata.

Therapeutic Uses: • Chronic, non-productive cough

Adverse Effects: • GI distress (nausea, constipation) – take ĉ food, fluid/fiber

• CNS sedation effects: Respiratory depression (<12/min) – naloxone

• Potential for abuse, schedule II.

Contraindications/Precautions: ♀ (C) •

• CI: acute asthma, head trauma, liver/renal dysfunction, acute alcoholism

Mucolytics

N203ATI (Unit 8)

Respiratory System -

Expected Action: Proto: acetylcysteine (Mucomyst) — Others: hypertonic saline

• Enhance flow of secretions in the respiratory passages

Therapeutic Uses: • Acute & chronic pulmonary disease ĉ secretions

• Cystic fibrosis • Acetylcysteine is the antidote for acetaminophen poisoning

Adverse Effects: • Aspiration and bronchospasm

Contraindications/Precautions: ♀ (B) • CI: GI bleeding

• Caution: Peptic ulcers / esophageal varices / severe liver disease

Education: • Has smell of rotten eggs • Dilute in fruit juice

• IV: Loading dose, next dose over 4h, last dose over 16h.

Decongestants

N203ATI (Unit 8)

Respiratory System -

Expected Action:

Proto: Phenylephrine Others: Ephedrine, naphazoline, phenylpropanolamine

• Stimulate α1-adrenergic receptors inflammation of nasal membranes

Therapeutic Uses: • Allergic rhinitis, sinusitis, and common cold

Adverse Effects: • Rebound congestion (Max 3-5 days, taper down use)

• CNS stimulation (rare ĉ topical) • Vasoconstriction

Contraindications/Precautions: ♀ (?) • CI: Chronic rhinitis

• Caution: CAD and hypertension

Education: • Oral do not lead to rebound congestion