Asthma inhalers: Which one's right for you?

Inhalers allow people with asthma to lead active lives without fear of an attack. Here's a rundown of inhaler types, with tips on proper use.

By Mayo Clinic staff

Inhalers have transformed asthma treatment. They enable children and adults with asthma to deliver medicine directly to their lungs nearly anytime and anywhere. A variety of inhalers are available to help relieve or control asthma symptoms.

Types of inhalers

Inhalers are hand-held portable devices that deliver medication directly to the lungs. A variety of inhalers exist, but they basically fall into two categories:

Metered dose inhalers
These inhalers use a chemical propellant to force a measured dose of medication out of the inhaler. They consist of a pressurized canister containing medication, a mouthpiece and a metering valve that dispenses the correct dose of medication. The medication is released either by squeezing the canister or by inhaling. You may find it easier to use a hand-actuated inhaler with a spacer — a short tube that attaches to the inhaler. Using a hand-actuated inhaler to release the medication into the chamber gives you time to inhale more slowly. It decreases the amount of medicine that's deposited on the back of your throat and increases the amount that ultimately reaches your lungs.

Some metered dose inhalers have counters so that you know how many doses remain. If there is no counter, you have to track of the number of doses you've used so that you know when the inhaler is out of medication.

The chemical propellant in metered dose inhalers has traditionally been a chlorofluorocarbon (CFC). But after an international agreement to ban CFCs because they damage the ozone layer, other propellants such as hydrofluoroalkane (HFA) are now used instead. The dose of medication released by an HFA inhaler may feel softer and warmer than the dose released by a CFC inhaler. If you're used to a CFC inhaler, it may not seem like a complete dose — even though the medication is reaching your lungs.

Dry powder inhalers
These inhalers don't use a chemical propellant to push the medication out of the inhaler. Instead, the medication is released by breathing in more quickly than you would with a traditional metered dose inhaler.

Some people find dry powder inhalers easier to use than the conventional pressurized metered dose inhalers because hand-lung coordination isn't required. Some models require operating a cocking device that requires dexterity. Available types include a dry powder tube inhaler, a powder disk inhaler and a single-dose dry powder disk inhaler. Spacers shouldn't be used with dry powder inhalers.

Comparing inhaler types
Choosing the right kind of inhaler for you depends on several factors, such as your hand-breath coordination, your dexterity, whether you can take a deep, fast breath, and what types of medication you need. The chart below can help you understand the pros and cons of each type. Work with your doctor to find the best inhaler for your needs.

Inhaler features

Metered dose inhaler	Metered dose inhaler with a spacer	Dry powder inhaler
Portable and convenient	Less portable and convenient, more complex and more expensive than a metered dose inhaler without a spacer	Portable and convenient
Doesn't require a deep, fast breath	Doesn't require a deep, fast breath	Requires a deep, fast breath
Accidental exhalation before activation won't disrupt medication	Accidental exhalation before activation won't disrupt medication	Accidental exhalation before activation will blow away medication
Hand-actuated models without a spacer require hand-breath coordination	Hand-breath coordination is not critical	Hand-breath coordination is not necessary
Can result in large amounts of medication on the back of your throat and tongue	Less medication settles on the back of your throat and tongue	Can result in large amounts of medication on the back of your throat and tongue
Minimal or no maintenance required	Spacer requires periodic cleaning with soap and water	Minimal or no maintenance required
Some models require you to keep track of how many doses remain	Some models require you to keep track of how many doses remain	It is clear when the device is out of medication
Requires shaking and priming	Requires shaking and priming, correct use of spacer	Single-dose models require loading capsules for each use
Humidity does not affect medication	Humidity does not affect medication	High humidity can cause powdered medication to clump

Medications delivered through inhalers

Inhalers are used to deliver a variety of asthma medications — some that assist with long-term control and others that provide quick relief of symptoms. Some medications may only be available in certain inhaler types. Inhaled asthma medications include:

• Short-acting bronchodilators. These medications, including albuterol (Proventil, Ventolin) and pirbuterol (Maxair), provide immediate relief of asthma symptoms.
• Long-acting bronchodilators. These medications relieve asthma symptoms for longer periods of time. They include salmeterol (Serevent) and formoterol (Foradil).
• Corticosteroids. Used long term to prevent asthma attacks, these medications include beclomethasone dipropionate (Qvar), fluticasone (Flovent), budesonide (Pulmicort), triamcinolone acetonide (Azmacort) and flunisolide (Aerobid).
• Cromolyn or nedocromil. These nonsteroidal medications are used long term to prevent inflammation.
• Corticosteroid plus long-acting bronchodilator. This medication combines a corticosteroid and a long-acting bronchodilator (Advair, Symbicort).

Inhalers may come with slightly different instructions. Follow those instructions carefully and ask your doctor for a demonstration.

The importance of using inhalers properly

It's important that you use your inhaler correctly so that the medication reaches your lungs. Carefully follow the instructions. And ask a doctor, nurse or pharmacist for a demonstration. Use the inhaler in front of this person and ask for feedback. Then practice at home in front of a mirror.

If you're unable to use an inhaler, a nebulizer may be an option. Nebulizers are designed for those who can't use an inhaler, such as infants, young children and those who are seriously ill. The device works by converting medication into a mist and delivering it through a mask that you wear over your nose and mouth.

Using an inhaler is just one part of your asthma treatment plan, which may also include checking your lung function with a peak flow meter, eliminating asthma triggers and exercising. But knowing what types of inhalers are available and how to use them can help you better manage your asthma and get the most from your treatment.

HQ01081

Aug. 17, 2007