2. Pulmonary Drug Delivery system
“Pulmonary drug delivery describes various
systems,devices,formulations & method of delivery of
drugs to the lung for the treatment of:
Diseases of the respiratory tract.
For systemic delivery via the drug.”
Once the drug is administered they readily pass into
the blood stream without the need of any enhancers
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5. Mechanism of drug
absorption
Drug diffusion through alveoli.
Absorption through aqueous pores by carrier
mediated transport.
phagocytosis of insoluble particles allow absorption
of compounds with low lipophilicity & or high
molecular weight.
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6. Inhaleables
Advanced technology for pulmonary delivery is
expanding a category of drugs called Inhaleables defined
as respiratory & systemic therapies administered simply
by inhaling.
Advantages:
It supply drugs into the blood stream directly.
It provide a non-invasive method of drugs delivery.
It furnish very rapid onset of action similar to I.V.route.
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7. Aerosols
Aerosol preparations are stable suspensions of solid
material & liquid droplets in a gaseous medium.
The drug delivery by aerosols is deposited in the
airways by:
Gravitational sedimentation
Diffusion
The term atomizer is used for a device that generates
an aerosol & may be powdered by
electrically/mechanically.
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8. Advantages of an aerosol
A dose can be removed without contamination of
remaining material.
The medication can be delivered directly to the
affected area in a desired form such as spray or
stable form.
Irritation produced by mechanical application of
topical medication is reduced or eliminated.
Minimum contamination.
Maximum stability.
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9. Limitations of aerosols
Poor patient compliance.
Irritant activity .
Increase bronco constriction.
High cost of mfg.
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10. Formulation of aerosol
Aerosol product essentially consists of two
components:
Product concentrate
Propellant
Product concentrate consist of active ingredients or
mixture of active ingredients
Other necessary agents such as solvents, antioxidants
& Surfactants.
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11. Propellant
Single or blend of various propellants are used.
It is selected to give the desired vapour pressure,
solubility & particle size.
Propellants can be with active ingredients in many
different ways producing products with varying
characteristics.
Depending on the type of aerosol system utilized,the
pharmaceutical aerosol may be dispensed as fine mist,wet
spray & semi-solid or solid.
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14. Metered dose inhalers(MDIs)
Is a device that helps to deliver a specific
amount of medication to the lungs.
It is commonly used to treat asthma, chronic
obstructive pulmonary disease(COPD).
It is composed of 4 essential components.
1.The base formulation-
drug ,propellant,excipients.
2.The container.
3.Metering valve .
4.The actuator (mouth piece).
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15. Propellants:
Commonly CFC propellants are used because of their
low pulmonary toxicity , high chemical stability and
purity and compatibility, Non-inflammable.
But now a days the CFC propellants are replaced with
Hydrofluoroalkanes(HFAs) as these CFC cause the
ozone depletion effect.
Examples: trichlorofluromethane
dichlorodifluoromethane
1.2.dichlorotetrafluromethane.
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16. Surfactants
These are added to maintain the drug in dispersed
state & promotes stability of formulation.
It is also lubricates the valve.
Examples : oleic acid ,sorbitol.
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17. Containers & valve
Usually the container is made up of aluminum or
glass.
Glass containers are normally plastic coated or
laminated to enhances their ability to ensure internal
pressures of high magnitude.
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18. Metering valves
These are designed to release a fixed volume of
product during each actuation.
Usually valves volumes range from 25 to 100ml
although larger volume are available.
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19. DRY POWDER INHALERS
This device dispenses a powder in a stream of inspired
air.
These are environmentally friend since they do not
require CFC propellants for drug dispersion.
Self medication is possible.
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21. Advantages
Product and formulation stability
High drug volume delivery per puff
low susceptibility to microbial growth
Applicable to both soluble and insoluble
drugs
Self medication is possible
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22. Disadvantages :
Hygroscopic powders have chances to
particle growth.
Accurate dose is required .
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23. Nebulizer
Nebulizers are those that aerosolize aqueous
solutions of water-soluble drugs 0r
suspensions & solvent-water based solutions of
water- insoluble substances.
Nebulizer have been successfully employed for
drug delivery to the lung.
It is also used for local drug delivery to trachea
for local anesthesia 23
24. There are two types of Nebulizer
1. Pneumatic Nebulizer :-It derives from
pressurized gas source
ex:- jet or hydro dynamic type
2. Electrical Nebulizer :-It operates from an
electric source
ex:-ultra sonic Nebulizer
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25. Therapeutic application:
For the treatment of asthma
Pulmonary infections
For chronic obstructive pulmonary disease
Cardio vascular agents
Blood glucose modifier
Lung cancer
Cystic fibrosis
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26. List of marketed products
Ventolin albuterol sulfate
Asmol sulbutamol
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27. REFERENCES
1.CONTROLLED DRUG DELIVERY CONCEPTS AND
ADVANCES BY-S.P.VYAS & R.P.KHAR
2.MODERNPHARMACEUTICS FOUTH EDITION BY-
BANKER & RHODES
3.ADVANCE IN CONTROLLED AND NOVEL DRUG
DELIVERY BY-N.K. JAIN
4. Google.com
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