What are the Different types of Metered Dose Inhalers (MDI)

Metered dose inhalers are delivered directly to the lungs via inhalation. The inhalers consist of a small aerosol canister with or without a counter. There are several types of metered dose inhaler that deliver a variety of medications to effectively treat many respiratory diseases, including asthma, COPD (chronic obstructive pulmonary disease), emphysema and chronic bronchitis.

Metered dose inhaler can be used alone, but it is highly recommended that you use a Spacer / Holding chamber attached to the inhaler because it helps you get more medicine into your lungs. Several different types or combinations of medicines are available as metered-dose inhalers.

Inhaled Corticosteroids

Spacer with Metered dose inhaler

types of MDI Metered dose inhalers with corticosteroids control respiratory disease by suppressing overactive immune response in the lungs which can cause inflammation. Lung Inflammation constricts airways and irritates the lungs, leading to spasms in the smooth muscles lining the lungs. Metered dose inhalers are available in various brand names such as Flovent, Azmacort, Beclovent, Vanceril, Budesonide, Qvar and Aerobid. Please do not discontinue use of corticosteroids without your doctor supervision, as steroid dependency can develop resulting in withdrawal from abrupt discontinuation.

Metered dose bronchodilators relax the smooth muscles of the lung airways preventing spasms that restrict or cut off the air supply. There are two types of bronchodilators available: long acting and short acting. Serevent (salmeterol) and Foradil (formoterol) are long-acting bronchodilators taken twice a day and are used to prevent acute bronchospasm. Short-acting bronchodilators are used to treat acute bronchospasm and are often called "rescue inhalers." They are available in different brand names as Ventolin, Proventil, Maxair, Xopenex, Alupent and ProAir.

Combination Inhalers
Corticosteroids and long-acting bronchodilators are also available in combinations for ease of use and efficacy. There is evidence that use of long-acting bronchodilators without an inhaled corticosteroid increases the risk of death during an asthma attack, which makes combination metered dose inhaler medications more popular. Brand names available for metered dose inhalers combining both a steroid and bronchodilator are Advair and Symbicort. Because of the corticosteroid component, these inhalers should not be discontinued suddenly without your Physician’s advice.

Source: www.aaaai.org