Resp summary 2 Flashcards
(12 cards)
What is the difference between local and systemic drug delivery in respiratory care?
Local: Targeted site, rapid onset, minimal side effects, avoids first-pass effect (e.g., nasal sprays, inhalers)
Systemic: Whole body action, variable onset, more side effects, may undergo first-pass (e.g., oral tablets, IV)
What are the advantages of nasal drug delivery?
- Non-invasive and self-administered
- Highly vascularised → rapid absorption
- Avoids first-pass metabolism
- Can bypass blood-brain barrier
- Useful in emergencies (e.g., naloxone)
What are the challenges of nasal drug delivery?
- Mucociliary clearance reduces residence time
- Enzymatic degradation of peptides/proteins
- Nasal irritation
- Anatomical variability among patients
What are common nasal formulations and their uses?
Solutions/Sprays: Decongestants, corticosteroids
Powders: Vaccines, biologics
Gels: Prolong contact
Inserts: Controlled release
Liposomes/Nanoparticles: Enhance stability and absorption
What formulation factors affect nasal drug performance?
- pH (4.5–6.5)
- Osmolarity (preferably isotonic)
- Viscosity (higher = longer residence)
- Preservatives (e.g., potassium sorbate)
What device engineering factors influence nasal delivery?
- Spray pattern
- Droplet size and spread
- Metered dosing for accuracy
What is an example of a well-designed nasal spray formulation?
Rhinocort Aqua (Budesonide): pH 4.5, 5% dextrose, cellulose for viscosity, 32 μg micronised budesonide per spray
What are common uses of inhalation therapy in respiratory care?
Asthma, COPD, nicotine replacement, systemic insulin delivery
What inhalation devices are commonly used?
- Metered Dose Inhalers (MDIs)
- Dry Powder Inhalers (DPIs)
- Nebulisers
What formulation and patient factors affect inhalation therapy?
- Particle size <5 µm for lung penetration
- Use of propellants, dispersing agents
- Humidity and breathing technique
What are other local routes relevant to respiratory pharmacy?
Topical: Skin corticosteroids
Ophthalmic: Antihistamine eye drops
Rectal/Vaginal: Hormones, pain relief, infection treatment
Summarise the principles of drug delivery in respiratory care.
- Local delivery = faster, fewer side effects
- Nasal delivery = treats local/systemic conditions
- Formulation/device design is critical
- Understanding anatomy and patient factors ensures effective use
