Antihistamines, Decongestants, Antitussives & Expectorants


URI caused by influenza or a rhinovirus --> inflammatory response --> excessive mucous production -->Symptoms: sore throat, coughing, upset stomach, sneezing and nasal congestion
Symptomatic Treatment: Antihistamines, Decongestants, Antitussives & Expectorants


Antihistamine
· Substances capable of reducing the physiologic and pharmacologic effects of histamine, including a wide variety of drugs that block histamine receptors
· H1 antagonists-compete with histamine for receptors-can’t remove histamine from receptor-reduces dilation of blood vessels & increased permeability-reduces salivary, gastric, lacrimal & bronchial secretions
· Two types Traditional & Non-sedating/peripheral acting
Traditional
· Diphenhydramine (Benadryl)
§ Used for allergies, motion sickness, sleep disorder, common cold
§ Drowsiness and has anticholinergic effects
§ No driving, heavy machinery, alcohol or CNS depressants
§ Caution use with asthma, COPD, PUD, BPH, HTN, pregnancy, cardiac and renal diseases. Contraindicated with acute asthma
Non-sedating/peripheral acting
· Fexofenadine (Allegra)
· Loratadine (Claritin)
· Cetirizine (Zyrtec)
§ Non-sedating, work peripheral to block actions of histamine
§ Headache, stimulation, drowsiness, constipation, urinary retention
§ Increased compliance due to longer duration of action

http://www.youtube.com/watch?v=ywdk3BTjK2s&NR=1


Decongestants
· Drugs that reduce congestion or swelling, especially of the upper and lower respiratory tract
· Three main types: Adrenergic, Anticholinergic & Corticosteroid
Adrenergic
· Pseudoephedrine (Sudafed)
v Oral route delayed onset with prolonged effect, less potent than topical, no rebound congestion
· Oxymetazoline (Afrin)
· Phenylephrine (Neo-Synephrine)
v Topical/Inhaled route quicker onset, more potent and rebound congestion
§ Relief of nasal congestion
§ Nervousness, insomnia, palpitations, tremors, HTN
§ Avoid caffeine, report fever, cough or other symptoms that persist longer than one week
Anticholinergic
· Ipratropium (Atrovent)
§ Prophylactic use for chronic nasal congestion
§ Anxiety, dizziness, headache, dry mouth
Corticosteroid
· Beclomethasone (Beconase)
§ Anti-inflammatory effect, “turns down” immune response
§ Local mucosal dryness and irritation

Antitussives
· A drug that reduces coughing, often by inhibiting neural activity in the cough center of the CNS
· Treat non-productive cough or dry cough
· Two types Opioid and Non-opioid
Opioid
· Codeine (Robitussin A-C)
· Hydrocodone
§ Stops cough reflex
§ Sedation, nausea, vomiting, lightheadedness & constipation
§ Avoid driving or operating heavy equipment
§ Report cough that persists more than a week, persistent headache, fever, rash
Non-opioid
· Dextromethorphan (Vicks Formula 44 & Robitussin-DM)
v Stops cough reflex without CNS depression
· Benzonatate (Tessalon Perles)
v Numbs stretch receptors in respiratory tract, prevents reflex stimulation
§ Dizziness, nausea
§ No liquids for 30 minutes after chewable tablet or lozenges
§ Report cough that persists more than a week, persistent headache, fever, rash

Expectorants
· Drugs that increase the flow of fluid in the respiratory tract, usually by reducing the viscosity of bronchial and tracheal secretions, and facilitate their removal by coughing and ciliary action
· Direct stimulation of secretory glands increases production
· Treatment for productive cough
· Guaifenesin (Mucinex, Robitussin Chest Congestion)
§ Thinner mucous is easier to move
§ N/V, gastric irritation
§ Report cough that persists more than a week, persistent headache, fever, rash
§ Caution with elderly, asthma, respiratory insufficiency
§ Increase fluids to liquefy and loosen secretions


Bronchodilators and Respiratory Agents

· Bronchodilators-medications that improve airflow by relaxing bronchial smooth muscle cells
· Beta-adrenergic agonists, anticholinergic, antileukotriene, corticosteroids & mast cell stabilizer

Xanthine derivatives
· Thephylline (Theo-dur)
· Caffeine
§ Taken systemically; relief of bronchospasm; CNS & CV stimulation-diuretic effect
§ N/V, anorexia, sinus tachycardia, palpitations, gastroesophageal reflux during sleep
§ Contraindicated Hx of PUD or GI disorders; caution cardiac disease

Beta-adrenergic agonists
· Epinephrine
v Non-selective, stimulates alpha and beta2 receptors
v Insomnia, restlessness, anorexia, vascular headache, hyperglycemia, tremor & cardiac stimulation
· Albuterol
v Selective, stimulates beta2 receptors
v HTN or HypoTN, vascular headaches, tremor
§ Relief of bronchospasm related to asthma, bronchitis, other pulmonary diseases
§ Activation of beta2, receptors; relaxes smooth muscles of airway and other organs; results in bronchodilation and increased airflow
§ Take medication as prescribed, do not skip or double up

Anticholinergic
· Ipratropium bromide (Atrovent)
§ PREVENT bronchoconstriction, not used for acute asthma exacerbations
§ Dry mouth or throat, GI distress, headache, coughing & anxiety

Antileukotrienes
· Montelukast (Singulair)
§ Prophylaxis and chronic treatment for ages 12 and up; approved for two years and up. Blocks leukotrienes
§ Take every night on continuous schedule even when symptoms improve
§ Assess liver function before therapy; Multiple drug interactions so check OTC and prescriptions with physician

Corticosteroids
· Beclomethasone dipropionate (Beclovent, Vanceril)
· Triamcinolone acetonide (Azmacourt)
· Fluticasone (Flovent, Fionase, Advair)
§ Treatment of bronchospastic disorders that are not controlled by conventional bronchodilators
§ Pharyngeal irritation, coughing, dry mouth, oral fungal infections; if discontinuing wean by physician
§ Contraindicated-fungal infections, AIDS, TB; Caution with diabetes, glaucoma, osteoporosis, PUD, renal disease, HF & edema
§ Teach patients to gargle and rinse with water to prevent fungal infections
§ Report weight gain >5lbs/week & chest pain to physician

Mast Cell Stabilizer
· Cromolyn (NasalCrom, Intal)
§ Used prophylactically, stabilizes cell membranes of inflammatory cells: provides anti-inflammatory response
§ Coughing, change in taste, sore throat, dizziness, rhinitis, headache & bronchospasm
§ Contraindicated for acute exacerbations; therapeutic effects may not be seen for up to 4 weeks; not recommended for kids under 5 years
§ Teach patients to gargle and rinse with water to minimize irritation to throat and oral mucosa




Questions:

1) Name the drug(s) that work peripherally to block actions of histamine

2) Name the drug(s) that can be used as a prophylactic for chronic congestion

3) Is Sudafed given PO or Topically? What are the +/- traits of this route for Sudafed?

4) Antitussives are used for a productive or non-productive cough?

5) Which drug relieves a dry cough by stretching the receptors of the respiratory tract?

6) What is the mechanism of action for Guaifenesin?

7) Name the mast cell stabilizer, why is it important to gargle and rinse?

8) Name the drug(s) that is/are used for treatment when bronchospastic disorders are not controlled by conventional bronchodilators

9) Name the drug that blocks leukotrienes

10) Name of the non-selective adrenergic bronchodilator






Answers:

1) Name the drugs that work peripherally to block actions of histamine
  • Fexofenadine (Allegra)
  • Loratadine (Claritin)
  • Cetirizine (Zyrtec)

2) Name the drug(s) that can be used as a prophylactic for chronic congestion
  • Ipratropium (Atrovent)

3) Is Sudafed given PO or Topically? What are the +/- traits of this route for Sudafed?
  • Sudafed is given PO
  • Oral route has a delayed onset with prolonged effect, is less potent than a topical and there is no rebound congestion

4) Antitussives are used for a productive or non-productive cough?
  • Non-productive

5) Which drug relieves a dry cough by stretching the receptors of the respiratory tract?
  • Benzonatate (Tessalon Perles)

6) What is the mechanism of action for Guaifenesin?
  • Guaifenesin works by stimulating the secretory glands which increase production; this leads to GI irritation which leads to the thinning and loosening of the secretions, thus making it easier to move.

7) Name the mast cell stabilizer, why is it important to gargle and rinse?
  • Cromolyn (NasalCrom, Intal)
It is important to gargle and rinse with water to minimize irritation to throat and oral mucosa

8) Name the drug(s) that is/are used for treatment when bronchospastic disorders are not controlled by conventional bronchodilators
Beclomethasone dipropionate (Beclovent, Vanceril)
Triamcinolone acetonide (Azmacourt)
Fluticasone (Flovent, Fionase, Advair)

9) Name the drug that blocks leukotrienes
  • Montelukast (Singulair)

10) Name of the non-selective adrenergic bronchodilator
  • Epinephrine


References

Lilley, L. L., Harrington, S. & Snyder, J. S. (2005). Pharmacology and the nursing process. St. Louis, MO: Mosby.
Petges, Nancy, RN MSN. Antihistamines, Decongestants, Antitussives and Expectorants Power Point, 2011
Petges, Nancy, RN MSN. Bronchodilators and other Respiratory Agents Power Point, 2011
Petges, Nancy, RN MSN. Antihistamines, Decongestants, Antitussives, Expectorants and Bronchodilators Study Guide, 2011