Routes of Administration - Inhalation

Question 1

Emergency supply of salbutanol

Answer 1

• Emergency supply of prescription only inhaler

Question 2

How to use a salbutamol inhaler

Answer 2

• Remove cap (some must be squeezed at the sides to release)
• Check dose counter (if device has one)
• Hold inhaler upright and shake well
• Breathe out gently (away frominhaler)
• Put mouthpiece between teeth (without biting) and close lips to form good seal
• Start to breathe in slowly through mouth and at the same timepress down firmly on canister
• Continue to breathe in slowly and deeply
• Hold breath for about 5 – 10 seconds or as long as comfortable
• While holding breath, remove inhaler from mouth
• Breathe out gently (away from inhaler)
  If more than onedose is needed, repeat all steps - starting fromstep 3
• Replace cap

Question 3

Side effects of the inhalation route

Answer 3

• Respiratory adverse effects were reported, including increased risks of respiratory infection, cough, pharyngitis, and rhinitis

Question 4

Solid in gas

Answer 4

Solid particles suspended in air

Question 5

Liquid in gas

Answer 5

Liquid particles suspended in air

Question 6

Branching of lung effect on inhalation

Answer 6

• Radius halfs therefore causing resistsnce from the trachea to the alveoli

Question 7

Obstructive lung disease

Answer 7

• Asthma
• COPD
• Cystic fibrosis

Question 8

Restrictive lung disease

Answer 8

• Interstitial lung disease, such asidiopathic pulmonary fibrosis
  Obesity

Question 9

Drug delivergy to the lungs

Answer 9

• Particles entering the respiratory tract are prevented from reaching the terminal bronchioles and alveoli by mechanisms which cause them to be caught by the mucous sheath lining the tubules

Question 10

Inertial impaction

Answer 10

• Upper airways when the velocity and mass of the particles cause them to impact the airway surface

Question 11

Factors that Inertial impaction

Answer 11

The particle’s momentum (dependent upon size!)
The position of the particle in the airstream of the parent branch
The angle of bifurcation

Question 12

Hyperventilation effect Inertial impaction

Answer 12

Impaction is of significance for the largest particles moving at the highest speed in the respiratory tract

Question 13

Sedimentation

Answer 13

• Particles suspended in a gas are subject to the vertical gravitational force
• Depositing in the lower/peripheral airways
• influenced by breath-holding, which allows more time for gravity to have an effect

Question 14

Diffuision during inhalation

Answer 14

The smaller the particles, the more they deposit via diffusion in the peripheral lung and alveolar space

Question 15

Minor mechanism of deposition

Answer 15

• Interception for elongated particles
• Charge reflection for charged particles

Question 16

Aerodynamic diameter

Answer 16

• Dependent on the geometric diameter (dg), shape factor (1 for spheres) and density (ρ) of the particle

Question 17

Factors Influencing lung deposition

Answer 17

• Particle size
• Particle size distribution
• Particle density
• Particle shape
• Particle hygroscopicity

Question 18

Cillia epithelial in airways

Answer 18

• Reduce drug deposition sweeping motion

Question 19

Mucociliary escalator

Answer 19

• Local drug concentration ↓

Question 20

Drug dissolution

Answer 20

• Local drug concentration ↑

Question 21

Macrophage clearance

Answer 21

• Local drug concentration

Question 22

Translocation/efflux

Answer 22

• Local drug concentration ↓

Question 23

Inhaler types

Answer 23

• Pressurized metered-dose inhaler + (spacer)
• Accuhaler / Diskus
• Handihaler
• Respimat
• Turbohaler
• (Nebuliser)

Question 24

Quality control

Answer 24

• Deposition of emitted dose
• Content uniformity
• Aerodynamic particle size distribution
• Spray pattern

Question 25

Advantages of local delivery of drugs to the lungs

Answer 25

• Drug delivered directly to target organ
• Lower doses may be required for optimal effect
• Rapid onset of action
• Fewer systemic side effects
• Non-invasive delivery

Question 26

Disadvantages of local delivery of drugs to the lungs

Answer 26

• Low efficiency of delivery
• Difficulty in breath coordination, manual handling of device, or breathing through the device
• Corticosteroid use can suppress immune response
• Throat irritation is possible

Question 27

Advantages of systemic delivery of drugs via the lungs

Answer 27

• Very rapid onset of action
• Circumvents first pass effect
• Non-invasive delivery route
• Good for biopharmaceuticals

Question 28

Disadvantages of systemic delivery of drugs via the lungs

Answer 28

• Low efficiency of delivery
• Some patients may have difficulty using some devices (handling and coordination)
  Some patients may have difficulty breathing (through the device)
• May need very low or very exact doses or special devices
• Expensive compared with oral therapies

Question 29

OTC inhaler

(Not to lngs but to cheek)

Answer 29

• Nicotine is vaporised and absorbed by the buccal mucosa into the bloodstream

Question 30

How to use Nicorette inhalator

Answer 30

• Line up the markers and pull each end in the opposite direction
• Insert the cartridge into the mouthpiece and twist to close securely
• When you have a craving take a shallow puff about every 4 seconds or take 2 deep puffs every minute. Each cartridge lasts for approximately 40 minutes of frequent puffing