Pulmonary drug delivery systemic diseases

Smola M, Vandamme T, Sokolowski A. Nanocarriers as pulmonary drug delivery systems to treat and to diagnose respiratory and non respiratory diseases. Int J Nanomed. 2008 3(1) 1-19. 

The first commercially available DPI system appeared on the market in 1949, developed and marketed by Abbott under the name Aerohaler. Like all early pulmonary drug-delivery devices, it delivered small-molecule compoimds (bronchodilators or inhaled corticosteroids) to the airways (not necessarily the deep limg) for the treatment of asthma or chronic obstructive pulmonary disease. Table 6 lists some of the early DPI systems used for asthma and COPD the energy somces in these devices were mechanical and patient inspiration. 

Most drug delivery systems currently used to treat pulmonary disease were developed and introduced into clinical practice long before assessments of pulmonary drug delivery were undertaken. The pharmaceutical companies have seen little reason to improve on the current devices, utilizing technology that is many decades old, because the current systems do produce useful therapeutic responses and are relatively safe ( therapeutic index ) if used effectively. 

Inhalation aerosols have been used for the delivery of drugs to the respiratory system since the mid-1950s. The most common dosage form for inhalation is the metered-dose inhaler (MDI), by which the drug is delivered from a pressurized container using a liquefied gas propellant. Medication delivered via this dosage form has allowed for a quick therapeutic response to the symptoms of asthma, emphysema, and chronic obstructive pulmonary disease (COPD), and has resulted in an improvement in the quality of life for millions of asthma sufferers. 

Inhalation Inhalation provides the rapid delivery of a drug across the large surface area of the mucous membranes of the respiratory tract and pulmonary epithelium, producing an effect almost as rapidly as by intravenous injection. This route of administration is used for drugs that are gases (for example, some anesthetics), or those that can be dispersed in an aerosol. The route is particularly effective and convenient for patients with respiratory complaints (for example, asthma or chronic obstructive pulmonary disease) as drug is delivered directly to the site of action and systemic side effects are minimized (see p. 219). 

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