Week 13 Notes Flashcards
What is the mechanism of action of antihistamines?
Block action by binding to H1 receptors causing decreased respiratory, vascular, and GI smooth muscle constriction and decrease in capillary permeability
What is the difference between 1st and 2nd generation antihistamines?
1st gen: bind non-selectively to central H1 receptors; 2nd gen: selective for peripheral H1 receptors
What are common side effects of antihistamines?
- Sedation
- Dry mouth
- Blurred vision
- Tremors
What are the precautions for 1st generation antihistamines?
- All on Beer’s criteria list
- Can cause paradoxical CNS stimulation in young children
- Contraindicated in patients with BPH, narrow-angle glaucoma; newborns, and premature infants
Name three 1st generation antihistamines.
- Diphenhydramine (Benadryl)
- Chlorpheniramine (Chlor-trimeton)
- Hydroxyzine (Atarax)
Name five 2nd generation antihistamines.
- Cetirizine (Zyrtec)
- Levocetirizine (Xyzal)
- Loratadine (Claritan)
- Desloratadine (Clarinex)
- Fexofenadine (Allegra)
What are intranasal antihistamines used for?
Treatment of seasonal allergic rhinitis and vasomotor rhinitis
What are common side effects of intranasal antihistamines?
- Somnolence
- Nasal irritation
- Bitter taste
List two examples of intranasal antihistamines.
- Azelastine (Astelin, Astepro)
- Olopatadine (Patanase)
What are the side effects of nasal corticosteroids?
- Nasal irritation
- Itching
- Sneezing
- Dryness
- Epistaxis
Name three nasal corticosteroids.
- Fluticasone (Flonase)
- Budesonide (Rhinocort)
- Triamcinolone (Nasacort)
What is the mechanism of action for decongestants?
Stimulate alpha receptors of vascular smooth muscle, constricting dilated arterioles within the nasal mucosa
What is the prototype oral decongestant?
Pseudoephedrine
What are common side effects of oral decongestants?
- Anxiety
- Restlessness
- Tremors
What is an absolute contraindication for oral decongestants?
Patients on MAOIs (can cause hypertensive crisis)
Fill in the blank: __________ is the most effective antitussive.
Codeine
What are nonopioid antitussives?
- Benzonatate
- Dextromethorphan
What is Guaifenesin used for?
Reduce the viscosity of thick sputum in the symptomatic treatment of cough due to respiratory infections
What are the common side effects of Guaifenesin?
- GI upset: N/V, diarrhea
What should patients do for Guaifenesin to work effectively?
Drink a ton of water
What is a precaution for using antitussives?
Should not be used in patients with respiratory disease who have chronic cough
True or False: Antitussives should be used for every cough.
False
What are the side effects of topical decongestants?
- Burning
- Stinging
- Dryness
- Sneezing
Fill in the blank: __________ is the only FDA approved expectorant.
Guaifenesin
