Respiratory Care Pharmacology

• Rau's Chapter 1 focuses on pharmacology in respiratory care.

Pharmacology and the Study of Drugs

• Drugs are chemicals altering an organism's functions or processes.
• Pharmacology studies drugs (chemicals), including their origins, properties, and interactions within living organisms.
• Respiratory Care Pharmacology applies pharmacology to cardiopulmonary disease and critical care.
• Pharmacy involves the preparation and dispensing of drugs.
• Pharmacognosy identifies the sources of drugs.
• Pharmacogenetics studies the interrelationship of genetic differences and effects.
• Therapeutics is the art of treating disease with drugs.
• Toxicology studies toxic substances and their pharmacologic action.

Naming Drugs

• Drugs have various names, including:
  • Chemical name
  • Code name
  • Generic name
  • Official name
  • Trade (Brand) name

Sources of Drugs

• Drugs can be derived from:
  • Animals, such as thyroid hormone, insulin, and pancreatic dornase
  • Plants, such as khellin, atropine, digitalis, reserpine, eucalyptus oil, and anise
  • Minerals, such as copper sulfate, magnesium sulfate, and mineral oil

Process of Drug Approval in the United States

• The process involves:
  • Chemical isolation and identification
  • Animal studies
  • Investigational New Drug approval, including Phase I, Phase II, and Phase III trials
  • New Drug Application
  • FDA new drug classification system
  • Approval of orphan drugs

The Prescription

• Prescriptions consist of several parts:
  • Patient name, address, and date
  • Rx symbol
  • Inscription: medication names / dosage
  • Subscription: the amount of medication to be given
  • Sig: directions for the patient
  • Prescriber's name
• Over-the-counter drugs do not require a prescription.
• Generic substitution in prescriptions involves using any manufacturer's version of the prescribed drug, which is generally less expensive.

Abbreviations Used in Prescriptions

• q: every
• qh: every hour
• qid: four times daily
• qod: every other day
• qd: every day
• q2h: every 2 hours
• q3h: every 3 hours
• q4h: every 4 hours
• po: per os (by mouth)
• prn: as needed
• IM: intramuscular
• IV: intravenous
• tid: three times daily

Respiratory Care Pharmacology Overview

• Involves aerosolized agents given by inhalation, which has five advantages.
• Includes related drug groups:
  • Anti-infective agents
  • Neuromuscular blocking agents
  • Central nervous system agents
  • Antiarrhythmic agents
  • Antihypertensive and antianginal agents
  • Anticoagulant and thrombolytic agents
  • Diuretics

Advantages of Aerosolized Agents Given by Inhalation

• Smaller doses are used compared to systemic administration.
• Fewer and less severe side effects compared to oral or parenteral delivery.
• Rapid onset of action.
• Targeted drug delivery to the respiratory system with lower systemic bioavailability.
• Painless and relatively safe inhalation of aerosol drugs, with convenience depending on the delivery device used.

Adrenergic Agents

• Beta-Adrenergic agents: cause relaxation of bronchial smooth muscle and bronchodilation, reducing airway resistance (Raw) and improving ventilatory flow rates in airway obstruction resulting from COPD, asthma, cystic fibrosis (CF), and acute bronchitis. Examples include Albuterol, Arformoterol, Formoterol, Levalbuterol, and Salmeterol.

• Alpha-Adrenergic agents: used for topical vasoconstriction and decongestion to treat upper airway swelling; Racemic Epinephrine is an example.

• Anticholinergic Agents: relax cholinergically induced bronchoconstriction to improve ventilatory flow rates in COPD and asthma. Examples include Glycopyrrolate bromide, Ipratropium Bromide, and Tiotropium Bromide.

Mucoactive Agents

• Modify the properties of respiratory tract mucus, reducing viscosity and promoting clearance of secretions.
• Examples are Acetylcysteine, Dornase Alfa, Mannitol, and Hyperosmolar Saline.

Antiasthmatic Agents

• Prevent the onset and development of the asthmatic response by inhibiting chemical mediators of inflammation.
• Examples include Cromolyn Sodium, Montelukast, and Omalizumab.

Anti-infective Agents

• Inhibit or eradicate specific infective agents.
• Examples are Ribavirin for RSV and TOBI for Pseudomonas Aeruginosa in CF or Influenza A and B.

Exogenous Surfactants

• Approved for clinical use via direct intratracheal instillation to restore more normal lung compliance in RDS of newborns.
• Beractant, Calfactant, Poractant Alfa, and Lucinactant are examples.

Prostacyclin Analogs

• Clinically indicated to treat pulmonary hypertension by decreasing shortness of breath and increasing walking distance.
• Examples: Iloprost, Treprostinil

Test your knowledge of respiratory care pharmacology. This quiz covers drug sources, the drug approval process, prescription components, and appropriate medications for respiratory conditions such as asthma and COPD, and upper airway swelling.