People with asthma often use inhalers (also called puffers) to take their medications. A spacer (also sometimes called a holding chamber) is a device that makes using an inhaler easier and more effective. It attaches to the inhaler on one end and to a mouthpiece or mask on the other end. When the medication from the inhaler is released into the spacer, it's held inside until it's slowly inhaled through the mouthpiece or mask. It doesn't require special coordination that the use of an inhaler alone requires. A spacer also helps deliver the medication to the airways - instead of the mouth and throat - where it can work better with fewer side effects.