PHARMACEUTICAL AEROSOL

Recent Advance in Aerosol

Presented by:

Matholiya Chetan

M. Pharm -III

(Pharmaceutics)

Guided by:

Mrs. Priya patel

Department of Pharmaceutical Science, Saurashtra University, Rajkot-360 005

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INHALATION AEROSOLS

• Airway is unique organ system of body and its structure allowing air to come into direct contact with blood. so this is a useful route of administration of drugs in the inhaled or aerosol form.

• The inhalation therapy provides fast acting treatment for respiratory illness such as asthma and chronic obstructive pulmonary disease (COPD).

• Compare to oral delivery, the inhalation of bronchodilator ,corticosteroids and other anti-inflammatory agent produce therapeutic level in the respiratory tract while maintaining low systematic concentration and minimum side effect.

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To be acceptable for clinical use an inhalation delivery system must meet certain criteria;

• It must generate an aerosol with most of the drug carrying particles less than 10μm in size, and ideally in the range 0.5 to 5 μm, the exact size depending on the intended application.

• It must produce reproducible drug dosing.

• It must protect the physical and chemical stability of the drug.

• It must be readily used by a patient with minimal training

 

Why inhalation therapy?

Oral

Slow onset of action

Large dosage used

Greater side effects

Not useful in acute

symptoms

Inhaled routeRapid onset, Better tolerated

Treatment of choice in acute symptoms

Better tolerated

What are the Inhalant drugs?

• Anti-allergic agentsBudesonideCromolyn sodium

• BronchodilatorsVentolin nebules (βagonist)Bricanyl solution (βagonist)

Inhalant drugs

• Mucolytic agentsAcetein (Acetylcysteine)

• Antimicrobials

TobramycinPentamidine RibavirinAmphotericin

Inhalant drugs

• Immune modulators

Cyclosporine

Interferon α

Interferon γ

• Vaso-active

Nitric oxide

• Anesthetics

Opioids

Inhalers

Breath Activated Inhaler

Nebulizer

Pressurized Metered Dose

Inhaler (pMDI)

Pressurized Aerosol

Inhaler with Spacer

Dry Powder Inhaler (DPI)

AN IDEAL INHALER

• High dosing efficiency (> 10-20%)• Small particle size < 5 microns• Simple to use & handle• Short treatment time• Small size, easy to carry• Multiple dose capability• Resistance to bacterial contamination• Cost effective• Efficient for specific drug used• Liked by patients!

Choice of device:

• Determined by –

•Drug to be delivered

•Age of patient

•Patient preference

Procedure

1. Turn on the compressor and use for the prescribed a mount of time.

2. Carefully monitor the child’s vital signs for adverse signs of reaction .

3. When finished the treatment , remove the mask from the child and turn of the compressor.

4. Assist the child to rinse the mouth with water .5. Return child to safe position in bed, with side rails up.6. Remove used equipments.7. Wash hand.8. Write documentation accurately .

NEBULIZERS

NEBULIZERS

Drugs Available for Nebulization

• Inhaled beta-2 agonist bronchodilators• Short-acting (3~6hr)• Long-acting (>12hr) eg. Salmeterol

• Inhaled anti-cholinergic• Inhaled corticosteroids• Nebulized Solutions

• Albuterol (Proventil®)• Ipratropium (Atrovent®)

• Inhaled medications delivered by an air compressor in the form of a fine spray

• Advantages:• Use of passive breathing• Good dosage form for a pediatric patient• Anything in solution can be nebulized

• Disadvantages:• Time intensive• Inefficient • Equipment and power source required• Cleaning required

NEBULIZERS

Overview of nebulizer designs:

• CONSTANT OUTPUT (“Traditional”)• e.g. most disposable SVNs: MistyNeb, Salter, FanJet

• BREATH ENHANCED• e.g. the PARI LC plusTM

• DOSIMETRIC (BREATH ACTUATED)• e.g. Monaghan AeroEclipseTM

Pari LC PlusBreath enhanced

AeroEclipseDosimetric

insulin Opioid delivery

AERx Delivery System

Classification of Nebulizers

• Size of the reservoir - small volume = approx. 6 ml - large volume = ≥ 500 ml

• Power source-pneumatic

- electric

• Method of aerosol production-mechanical (jet) - ultrasonic

Classification of Nebulizers

- orifice wick - babington - spinning disk - metered dose - DPI

• Placement in patient’s breathing tube - mainstream - sidestream - slipstream

TYPES OF NEBULIZERS

•Air jet nebulizer•Ultrasonic nebulizer •Babington nebulizer•Spinning disk (centrifugal) nebulizer

Air jet nebulizer

• It requires an external gas supply which is the driving force for liquid atomization

• The compressed gas is forced through the jet causing a region of negative pressure to develop as the gas is expelled at high velocity through the spray orifice.

• The separation between the spray nozzle and the baffle, and the droplet exit velocity from the nozzle, are of primary importance in defining the size of droplets that escape impaction.

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• Solvent losses due to evaporation cause solution remaining the reservoir to concentrate. This increase in concentration leads to drug or excipients crystallization within the reservoir.

• The major controllable operating variable associated is airflow rate through the nebulizer which is critically dependent on the driving pressure, except when the spray orifice acts as critical orifice.

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• Other variables , such as humidity, ambient temperature, and inspiratory flow rate, influence the nebulizer performance, but are difficult to standardize under patient use condition.

• Nebulizer are subdivide into single use and multiuse.

• Air-jet nebulizer are capable of successfully delivering respiratory suspensions.

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Ultrasonic Nebulizer

• Aerosol is produced by ultrasonic sound waves emitted from a vibrating transducer directed up through a reservoir of liquid (Piezoelectric principle)

• Frequency (usually 1.35 MHz) determines the particle size (1 - 10 µ)

• Amplitude control determines the volume of mist produced

• Output volume of 3 - 6 ml/min. (High!!!)• Not used on infants d/t fluid overload

Ultrasonic nebulizer

• external gas supply is not required• Respiratory solution or suspension is atomized by means

of a piezoelectric transducer.

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Babington Nebulizer

• Uses the principle of a jet stream of gas being directed through a thin film of continually flowing liquid spread across a rounded surface

• The gas penetrates the liquid surface causing aerosol particles to be formed, which are then baffled and sent to the patient

Spinning Disk (Centrifugal) Nebulizers

• Commonly called “room humidifiers”

• Uses principle of the Archimedean screw; a disk rotates around a hollow shaft that is immersed into a water reservoir; once the water reaches the spinning disk, it is thrown outward through breaker combs and aerosol particles are produced

• Can be a source of environmental contamination, should be cleaned periodically