context: How well do you know your asthma inhaler? What does it do for you? What drugs are in it? Do you puff and breathe, or breathe and puff? Inhalers are the most effective way to get lifesaving medications to people with asthma and other lung diseases. Whether you have asthma or care for someone who does, here's what you need to know about inhalers, including how to use one correctly. An asthma inhaler is a handheld device that delivers medication straight into your lungs. You get the drugs faster -- and with fewer side effects -- than you would if you took it by pill or IV. Asthma inhalers can deliver drugs in a variety of ways. Hydrofluoroalkane inhalers or HFAs (formerly called meter does inhalers) provide the drug through a small, handheld aerosol canister. They work like a spray can. You push the inhaler, it sprays out the medicine, and you breathe it in. A tube-like gadget called a spacer can help kids or people with trouble breathing use an HFA more easily. Dry powder inhalers ( DPIs) require you to breathe in quickly and deeply. That can make them hard to use during an asthma attack when you can't fully catch a deep breath. Read the instructions carefully if you get a different brand, because they vary widely and the new one may not work like your old one. Nebulizers deliver medication through a mouthpiece or mask. They're easier to use because you can breathe normally. That makes them good for children or people with severe asthma who may not be able to use an HFA or DPI properly. Many inhalers contain steroids, like prednisone, to treat inflammation. Others have a type of drug called a bronchodilator to open up your airways. Some have both -- this is known as a combination inhaler. Anti-inflammatory asthma inhalers prevent asthma attacks and reduce swelling and mucus in your airways. They include: Steroids ( Aerospan, Alvesco, Asmanex, Flovent, Pulmicort, and Qvar) Mast cell stabilizers (cromolyn sodium) For in-depth information, see Web MD's article on Asthma, Steroids, and Other Anti- Inflammatory Drugs. Bronchodilator asthma inhalers are either short or long-acting. They widen your airways to ease symptoms like wheezing, shortness of breath, and coughing. They include: Short-acting beta-agonists ( Pro Air HFA, Proventil HFA, Ventolin HFA, and Xoponex) Long-acting beta-agonists ( Foradil and Serevent). The combination inhalers containing both a long-acting beta-agonist and a steroid include Advair, Dulera, and Symbicort. Long-acting anticholinergics such as tiotropium bromide ( Spiriva Respimat), available for anyone ages 6 and older. This medicine can be used in addition to your regular maintenance medication. Combivent and Duo Neb inhalers contain both albuterol and ipratropium (a bronchodilator); albuterol and ipratropium may also be given using a nebulizer. For in-depth information, see Web MD's article on Bronchodilators: Relieving Asthma Symptoms. Many new inhalers include a dose counter to show how much medication is left. It's hard to tell with older models, most of which make a puff sound long after the medication is gone. This could be a serious problem if you need the inhaler and it's empty. The best way to tell how many doses remain is to mark the number of doses used on the inhaler and then toss it after you've used this number of puffs. You can find the total number of doses on the box or canister. Mark the date on your calendar when you expect to use all of the available puffs in the new inhaler, and replace it before then. Keep one or two extra quick-relief inhalers at home. A spacer is a tube that attaches to the inhaler and holds the medication until you can breathe it in. This makes the device easier to use and helps get the medication into your lungs. Not all inhalers are used with a spacer, so ask your pharmacist if you need one. Spacers with masks are available for use by small children or anyone else who can't breathe in through a standard spacer. See Web MD's articles for instructions on using an MDI inhaler with a spacer, without a spacer, and with a mask spacer.