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If the mouthpiece isn’t disposable, wash it with mild soap and water between uses to disinfect it and prevent the buildup of bacteria. Alternatively, you can use a new disposable mouthpiece every day. In some cases, your doctor may want you to keep track of how much air you’re able to inhale. Track your progress by writing down how far the piston moves upward each time you use the device. There are markings on the column that the piston is housed in that indicate how much air you’ve inhaled in milliliters. Stop using the device if you feel dizzy or lightheaded at any point. Rest for as long as necessary, then resume your breathing exercises with the incentive spirometer. Let your doctor know if using the device causes any of these symptoms, and follow their instructions going forward.

Summary:
Clean the mouthpiece after each use or use a new one every 24 hours. Keep a log of your progress for your doctor, if applicable. Report dizziness or lightheadedness to your doctor.