1. Graded Seminar
Dry Powder Inhaler
Submitted By-
Mr. Tejas Chandrakant Jagtap
M. Pharm (Pharmaceutics)
2nd Semister
Guided By-
Dr. (Mrs.) Shilpa P. Chaudhari
HOD, Pharmaceutics Dept.
Dr. D. Y. Patil College of Pharmacy,
Akurdi, Pune-44.
Dr. D. Y. Patil College of Pharmacy, Akurdi, Pune-411044.
2. Contents:
1. Background
2. Introduction & Definition
3. Types of DPI
4. Characteristics
5. Advantages
6. Disadvantages
7. DPI formulation
8. Carriers used in DPI
9. Techniques for DPI
10. Characterization of DPIs
11. References
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
3. Background:
Not used as commonly in the United States as are MDIs.
Greater variety in design and function of DPIs relative to MDIs.
Include Pre-metered and Device-metered DPIs.
Changes in design is done for reproducibility of the dose and particle
size distribution.
The most formidable challenge for DPIs is that to maintain the
qualities till expiration period and functionality of device.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
5. Dry Powder Inhalers (DPIs)
DPI is device that delivers medication to the lungs in the form
of dry powder. DPIs are also commonly used to treat Respiratory
Diseases such as asthma, bronchitis, emphysema and COPD.
Either in a capsule or Inside the inhaler itself.
Once loaded or actuated, the operator puts the mouthpiece of the
inhaler into the mouth and takes a deep inhalation.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
6. Dry Powder Inhaler (DPIs)
Commonly used to deliver medications such as inhaled
corticosteroids into the lungs.
This inhaler is breath-activated. The medication is released only
when you take a deep, fast breath in through the inhaler. This is
different than a metered dose inhaler that pushes medication into
the lungs.
Marketed examples of dry powder inhalers include:
Advair Diskus, Asmanex, Pulmicort flexhaler.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
9. Ideal Characteristics required for DPI’s
Effective Dosing.
Uniform dose through out life.
Targeted and optimize delivery:
Controlled respirable fraction.
Inhalation of dose-independent aerosol generation.
Bolus of aerosol available at the beginning of an inhalation.
Operable at low inhalation flow rates.
Continued….
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
10. Ideal Characteristics required for DPI’s
Good Environmental production.
Design optimized by the use of, for e.g., particle engineering,
manufacturing innovation, etc.
In-process controls for quality.
Compact, Portable, Cheap, Reusable and Efficient device.
Clear comparative data for complaint.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
13. DPI Formulation Considerations:
Consist of the API or carrier powder mixed with drug (API).
Particle size of drug should be < 5 μm.
The micronization of drug is done by milling, spray drying, and
supercritical fluid extraction.
Micronized drug particle achieve good aerodynamic properties of the
dispersed powder.
Improvement in formulation performance by development of tertiary
excipients like magnesium stearate and leucine.
Helps in improving the performance of formulation by interfering
with inter-particle bonding due to its antiadherent action.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
14. Carriers used in DPIs
Used to improve drug particle flow ability, improving dosing accuracy,
minimizing the dose variability.
To facilitate the easy emission of drug particles from capsules and
devices, thereby increasing the inhalation efficiency.
Design of the carrier particle is important for the development of DPIs.
Characteristics of carrier particles include physico-chemical stability,
biocompatibility and biodegradability.
Should be compatible with the drug substance and must be inert,
available and economical.
Examples of carriers: Lactose, mannitol, glucose, sorbitol, maltitol, and
xylitol.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
15. Advantages of lactose as a carrier
Well-investigated toxicity profile
Physical and chemical stability
Compatibility with the drug substance
Broad availability
Low cost.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
16. Techniques for DPI
A) Controlled crystallization or precipitation:
Crystallization, or precipitation, is the process by which
particles are produced from solution of the material in a suitable
solvent.
The formation of a stable, crystalline material is normally the
target of this final step.
In the production of materials for use in DPI products, however,
the particle size of the crystallized product is normally too large.
Subsequent reduction in particle size is then necessary and can
significantly alter the physical nature of the material.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
17. B) Micronization:
Micronization involves high energy particle-size reduction
technique that can convert coarse-diameter particles into particles <5µm
in diameter. Types of equipment used as, jet or fluid energy mills and
ball mills.
All techniques involve applying a force on the particle, typically in
the form of a collision, either particle-particle or particle-equipment.
As the size of the particle decreases, the number of imperfection
decreases.
Techniques for DPI
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
18. C) Blending:
It serves as a commonly used method for improving the flow ability, fill
ability, and dispersability of small cohesive particles wherein the drug is
blended with excipients particles.
The objective of the mixing process is to produce an ordered powder in
which the small particles attach themselves to the surface of larger “carrier”
particles.
The final product performance of a powder blend in DPI is ultimately
depends on the individual drug and carrier properties as well as on the process
by which they are blended.
Techniques for DPI
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
19. D) Pelletization:
The process involves deliberate agglomeration of the fine drug
material into less cohesive, larger units.
Pelletization is usually achieved by vibratory sieving or any process
that tumbles powder.
The resultant pellets must be used in a system capable of
deaggregating to an appropriate particle size for aerosol drug delivery.
Techniques for DPI
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
20. Characterisation of DPIs
Appearance &
Colour:
• Should be checked
for drug and device
• If any colour is
present with the
formulation,
quantitative test with
relevant acceptance
criteria should be
established
Particle Size
Analysis:
• Sieve Analysis
• Sieve Shaker
• Air-jet Sieving
• Laser Diffraction
• Sympatec (0.25 µm -
1750 µm) and
Malvern (0.01 µm-
6000 µm) supplies
instruments for laser
defraction.
Moisture Content:
• Affectes Aerosolization
of the particles, particle
size distribution,
crystallinity, dose
content uniformity,
microbial content, and
stability.
• Karl Fisher method
Impurities and
Degradation
Products:
• Acceptance criteria
should be set for
individual and total
degradation products
and maximum
impurities.
• Drug is checked
whether is in specified
limit or not.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
21. Characterisation of DPIs
Drug Content (Assay):
• Should be determined
analytically with a
stability indicating
method.
• Acceptance criteria
should as high as
possible.
Microbial Limits:
• Total Aerobic Count
• Total Yeast Count
• Mold Count
• Indicator Pathogens
Delivered Dose
Uniformity:
• Both air flow rate and
total volume of air drawn
through the device should
be thoroughly evaluated.
• Volume of air drawn
through the device be
limited to two litres.
• Apply For both D-M DPI
& P-M DPI.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
22. References:
1. https://www.aaaai.org/conditions-and-treatments/conditions-dictionary/dry-powder-
inhalers, dated on April14th, 2017.
2. Santosh Thorat, Tushar Mahajan, Sarika Meshram, ”Formulation And Product
Development Of Dry Powder Inhaler: An Overview”, World Journal Of Pharmacy And
Pharmaceutical Sciences, Volume 4, Issue 11, 639-655.
3. Paul J Atkins, “Dry Powder Inhalers: An Overview”, Conference Proceedings:
Respiratory Care, Volume 50, No. 10, 1304-1312.
4. “Guidance for Industry: Metered Dose Inhaler (MDI) and Dry Powder Inhaler (DPI) Drug
Products”, “Chemistry, Manufacturing, and Controls Documentation”, U.S. Department
of Health and Human Services, Food and Drug Administration, Centre for Drug
Evaluation and Research (CDER).
5. http://www.malvern.com/en/industry-applications/sample-type-form/powders-granules/,
dated on April26, 2017.
6. http://www.sympatec.com/EN/LaserDiffraction/INHALER.html, dated on April26, 2017.
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Dr. D. Y. Patil College of Pharmacy, Akurdi,
Pune-44.
