Bamboo is a natural material that will change appearance over time. The top portion of the bamboo which goes into your mouth may appear lighter and faded over time, which is normal and will not affect your brushing experience. Let air dry between each use.
Reuse or compost the handle
The American Dental Association recommends switching your toothbrush every 3 months. After that you can either compost your handle or even plant it in your garden!