Lecture Notes: Key Respiratory Medications

Expectorants

• Key Medication: Guaifenesin
  • Usage: For nonproductive cough associated with respiratory infections
  • Mechanism: Reduces viscosity of secretions, making cough more productive
  • Side Effects: Minimal, may include GI upset, dizziness
  • Patient Teaching: Take with a full glass of water

Mucolytics

• Key Medication: Acetylcysteine (Mucomyst)
  • Usage: Pulmonary disorders with thick mucus (e.g., cystic fibrosis); antidote for acetaminophen (Tylenol) overdose
  • Mechanism: Breaks down mucus molecules to reduce viscosity
  • Side Effects: Bronchospasm (use cautiously in asthma patients), nausea, vomiting, rash
  • Patient Teaching: Smells like rotten eggs (hint: "A" for Acetylcysteine, "A" smell)

Decongestants

• Key Medications: Pseudoephedrine, Phenylephrine
  • Pseudoephedrine
    • Usage: Rhinitis, nasal congestion
    • Mechanism: Vasoconstriction of respiratory tract mucosa
    • Side Effects: Nervousness, palpitations, weakness, insomnia, rebound congestion
    • Regulation: Behind pharmacy counter due to methamphetamine issues
  • Phenylephrine: Often used in OTC cold products instead of pseudoephedrine

Antihistamines

• Types:
  • First-Generation: Diphenhydramine (Benadryl)
  • Second-Generation: Loratadine (Claritin), Cetirizine (Zyrtec)
• Usage: Allergy symptoms (rhinitis, itchy/watery eyes, sneezing), motion sickness, urticaria (hives)
• Mechanism: Block H1 receptors, reducing histamine effects
• Side Effects:
  • First-Generation: Sedation, anticholinergic effects ("Can't pee, can't see, can't spit, can't poop")
  • Second-Generation: Fewer side effects
• Patient Safety: Fall precautions for diphenhydramine due to sedation

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• Conclusion: This concludes the discussion on respiratory medications. The next topic will be cardiovascular medications, which are more numerous.