This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (November 2007)

An aerosol metered-dose inhaler (MDI)

An inhaler or puffer is a medical device used for delivering medication into the body via the lungs. It is mainly used in the treatment of asthma and Chronic Obstructive Pulmonary Disease (COPD).

To reduce deposition in the mouth and throat, and to reduce the need for precise synchronization of the start of inhalation with actuation of the device, MDIs are sometimes used with a complementary spacer or holding chamber device.

[edit] Variants

There are several different types of inhalers. The most common is the pressurized metered-dose inhaler (MDI). In MDIs, medication is most commonly stored in solution in a pressurized canister that contains a propellant, although it may also be a suspension.^[1] The MDI canister is attached to a plastic, hand-operated actuator. On activation, the metered-dose inhaler releases a fixed dose of medication in aerosol form. The correct procedure for using an MDI is to first fully exhale, place the mouth-piece of the device into the mouth, and having just started to inhale at a moderate rate, depress the canister to release the medicine. The aerosolized medication is drawn into the lungs by continuing to inhale deeply before holding the breath for 10 seconds to allow the aerosol to settle onto the walls of the bronchial and other airways of the lung.

Besides the MDI, other types of inhalers include dry powder inhalers (DPIs), which release a dose of medicine as a powder aerosol that is inhaled by the patient, and nebulizers, which instead supply the aerosol as a mist created from an aqueous formulation.

The largest manufacturers of inhalers are GlaxoSmithKline (makers of the Advair Discus (a DPI)), Merck, AstraZeneca (makers of Pulmicort and Symbicort) and Boehringer-Ingelheim (makers of Atrovent, Combivent, and Spiriva). BI, GSK, Merck, and AstraZeneca manufacture the medication being delivered via inhaler. However, 3M Drug Delivery Systems does some of the finished product manufacturing, as they are one of the leaders of MDI canisters, metering valves and other components.

Recently, the FDA banned the use of inhalers that utilize CFCs (Chlorofluorocarbons) as propellants for the more the environmentally friendly HFA inhalers. While some asthma suffers and advocacy groups contend that these environmentally friendly inhalers are not as effective,^[2] published clinical studies indicate equivalent control of asthma is achieved with use of HFA inhalers. ^[3] Patients also are concerned with the high price of the HFA inhalers as there is no generic version, which was available in the CFC inhalers for many years.^[2]

[edit] Delivery

• Metered-dose inhaler or MDI
• Dry Powder Inhaler or DPI
• Nebulizer

[edit] Categories

• Bronchodilator Inhalers: Short-Acting Beta-2 Adrenergic Bronchodilator Inhalers
• Daily Inhalers: Long-Acting Adrenergic Bronchodilator Inhalers
• Daily Inhalers: Anticholinergic Bronchodilators in COPD
• Daily Inhalers: Corticosteroids
• Combination Inhalers: Corticosteroid with LongActing Beta-2 Adrenergic Agonist
• Combination Inhaler: Anticholinergics with Short- Acting Beta-2 Adrenergic Agonists^[4]

[edit] See also

• List of medical inhalants

[edit] Notes

[edit] References

[edit] External links

• Basics aspects of inhaled pharmaceutical aerosols
• Recent advances in spray medication technology
• Ourasthma.com – a patient-oriented site with information on asthma inhalers.
• Discrete simulation of powder dispersion in pharmaceutical aerosol inhalers

v • d • e Route of administrations / Dosage forms Oral Enteral/ digestive tract Solids Capsule · Pill · Tablet · Orally disintegrating tablet · Film · OROS (osmotic controlled release capsule) Liquids Elixir · Emulsion · Syrup · Suspension · Tincture Respiratory tract Inhaler (Metered-dose, Dry powder) · Nebulizer Circulatory system Sublingual administration ENT Eye drop · Ear drop · Intranasal Transdermal Emulsion (Ointment · Cream · Lotion · Liniment · Gel · Paste · Film)  · Medicated shampoo · Transdermal implant · Transdermal patch Injection/parenteral Subcutaneous (SC) · Intravenous (IV) · Intramuscular (IM) · Intraosseous · Intraperitoneal (IP) · Intrathecal · Intracavernosal Vaginal Pessary (vaginal suppository) · Vaginal ring · Douche · Intrauterine device Rectal Suppository · Enema