A closeup photo of a child getting a nebulizer treatment with a mask.
A Neb Treatment with a Mask
Photo (c) 2007 Vincent Iannelli, MD licensed to About.com, Inc.
In this closeup photo, you can actually see the medicine misting from the nebulizer holding chamber. If your nebulizer is not misting well, then it likely isn't working and may need to be repaired or replaced.
The end of misting is also a sign that an asthma treatment has ended.