Pulmonary + Intranasal Flashcards
By the end of weeks 1 and 2, you should be able to:
To describe the anatomy, physiology and function of the airways
To describe and discuss the mechanisms of, and barriers to, pulmonary drug absorption
To discuss the effects of formulation and physicochemical properties on pulmonary drug delivery using aerosols
To describe and discuss barriers and opportunities for pulmonary delivery of macromolecules
To understand the anatomy and function of the nasal cavity
To describe mechanisms of, and barriers to, nasal drug absorption
To discuss the effects of formulation and physicochemical properties on nasal drug delivery
To describe and discuss barriers and opportunities for nasal delivery of macromolecules
What type of diseases is pulmonary administration used to treat?
the prophylaxis /treatment of airways disease
Name 4 examples of airways disease
- asthma
- cystic fibrosis
- COPD
- infection
What advantages does pulmonary administration have over the oral route? (onset of action, dose, metabolism - 4)
- delivers drug directly to the site of action = rapid onset (in e.g. asthma attack)
- smaller doses than oral req
- useful for poorly absorbed/rapidly metabolised drugs
- avoids first pass metabolism
What are 7 types of drugs administered by the pulmonary route?
- bronchodilators
- corticosteroids
- anti-allergy
- mucolytics
- anti-infectives
- oxygen
- inhalational anaesthetics
What are 3 examples of bronchodilators?
- salbutamol
- ipratropium
- theophylline
What are 2 examples of corticosteroids?
- beclomethasone
- fluticasone
What are 2 examples of anti-allergy drugs?
- sodium cromoglicate
- nedocromil
What is an example of a mucolytic and what does it do?
- Pulmozyme™
- breaks down overproduction of mucus in lungs to make breathing easier
What are 2 examples of anti-infectives administered through the pulmonary route?
- colistin
- pentamidine
What are 2 examples of inhalational anaesthetics?
- halothane
- N2O
What are the 2 functions of the lung?
- oxygenation of blood, elimination of CO2
- preventing entry + promoting efficient removal of airborne foreign particles
The lungs are able to oxygenate and eliminate CO2 from the blood. This is accomplished by interaction and coordination of the lungs with what? (4)
- central nervous system
- diaphragm
- chest wall musculature
- circulatory system
What are the 3 regions of the respiratory system?
- nasopharynx region
- tracheobronchial region
- pulmonary region
- nasopharynx region
- nose
- mouth
- pharynx
- larynx
What makes up the tracheobronchial region? (3) What is it also known as?
- trachea
- bronchi
- bronchioles
conducting zone: helps air in and out of lungs
What makes up the pulmonary region? (2) What is it also known as?
- respiratory bronchioles
- alveoli
respiratory zone: O2, CO2
what does right lung have that left doesnt?
middle lobe.
still has inferior and superior though
what part of lungs is it most important whilst difficult to deliver drug to?
deep part of lungs: most alveoli, very narrow paths and more difficult to deliver drug
How many alveoli within the alveolar sacs? What is the surface area in an adult male?
Alveolar sacs contain ~ 3 x 10^8 alveoli
surface area ~ 70 - 80 m^2 in adult male
Greater SA = greater drug absorption
What specialised cells line the conducting airways? What do they do?
- lined with ciliated columnar epithelial cells, goblet cells and submucosal glands
- mucus moistens inspired air, prevents drying of the walls, and traps particulate matter (foreign particles, wafted out)
What cells are alveoli lined with? (2 types)
- Type 1 pneumocytes - 95% of SA, 40% of cells present
- Type 2 pneumocytes - 3% of SA, 60% of cells present
3 types of pulmonary drug devices?
nebulisers
DPI
pMDI
what is in an aerosol? used to delivery pulmonary drugs?
dispersion of solid/liquid in gas