Medical and Pharmaceutical Aerosols - Aerosols: Measurement, Dosimetry, and Health Effects - page 10

TABLE 1.2
Selected DPIs and Some of Their Properties

Powder
Supply Inhaler Company Energy Source Carrier Dosing Doses

Rotahaler ® GSK Passive Lactose Capsule Single dose 1

Spinhaler ® Fission/Aventis Passive None Capsule Single dose 1

Handihaler™ Boehringer Ingelheim Passive Lactose Capsule Single dose 1

Aerolizer™ Novartis Passive Lactose Capsule Single dose 1

Boehringer Ingelheim Passive Glucose Capsule Multiple unit dose 6

Inhalator ®

Diskus ® /
Accuhaler ®

GlaxoSmithKline Passive Lactose Blister Multiple unit dose 60

Aerohaler ® Boehringer Ingelheim Passive Lactose Capsule Multiple unit dose 6

Diskhaler ® GlaxoSmithKline Passive Lactose Blister Multiple unit dose 4, 8

Taifun ® LAB Pharma Passive Lactose Reservoir Multiple unit dose 200

Orion Passive Lactose Reservoir Multidose 200

Easyhaler ®

Airmax™ IVAX Passive Lactose Reservoir Multidose

Sofotec Passive Lactose Reservoir Multidose 200

Novolizer ®

Twisthaler ® Schering-Plough Passive Reservoir Multidose 60

Turbuhaler ® AstraZeneca Passive None Reservoir Multidose 200

Spiros ® Elan Pharmaceuticals Impeller N/A Blister,

Cassette

Single and
Multiple unit dose

1, 16,
or 30

Inhance™ Inhale Compressed gas Lactose Blister Single dose 1

Dynamic
Powder
Disperser™

Pfeiffer Compressed gas Lactose Cartridge Multiple unit dose 12

Jethaler ® RatioPharm GmbH Mechanical Lactose Ring tablet Single dose 1

Aspirair ® Vectura Compressed air Mannitol Blister Single dose 1

Source: Adapted from Dunbar, C. et al., KONA , 16, 7, 1998; Newman, S.P. and Busse, W.W., Respir. Med ., 96, 293, 2002;
Son, Y. and McConville, J.T., Drug Dev. Ind. Pharm ., 34, 948, 2008; Islam, N. and Gladki, E., Int. J. Pharm ., 360,
1, 2008.

of high-output nebulizers that shorten dosing times and increase drug delivery to the patient have
increased the usage of nebulizers. 98,99
However, some disadvantages related to their use include their lack of portability, use of other
accessories such as tubing, mouthpiece or facemasks, obstructive dosing, and cleaning require-
ments. 100 Others, depending on the nebulizer type, may include inter-device variability, greater costs
of drug delivery as a result of the need for extensive assistance from health-care personnel, and
requirement of high doses to achieve therapeutic effect. 91
Based on the mechanism of aerosol production, nebulizers can be classiied as air-jet or ultra-
sonic. In jet nebulizers, the aerosol is produced by applying a high-velocity air stream from a pres-
surized source at the end of a capillary tube; liquid can be drawn up the tube from a reservoir in
which it is immersed. When the liquid reaches the end of the capillary, it is drawn into the airstream
and forms droplets that disperse to become an aerosol. 16 In ultrasonic nebulizers, the solution is
aerosolized by the vibration of a piezoelectric crystal to induce waves in a reservoir of solution.
Interference of these waves at the reservoir surface leads to the production of droplets in the atmo-
sphere above the reservoir. An airstream is passed through this atmosphere to transport the droplets
as an aerosol. 101
Ultrasonic nebulizers require an electrical power source, which can either be AC (wall plug) or
DC (battery). The movement of the transducing crystal causes frictional heating, which increases the