A stethoscope is an investment for medical professionals, so many use it for several years before replacing parts or the entire device. Manufacturers recommend replacing a stethoscope every two years, but medical professionals are skeptical of this recommendation. People should look for signs that the device has worn down over time to get the most out of it. The earpieces, for example, are frequently the first component of a stethoscope to require replacement.  Replacement earpieces are included with most stethoscopes, but they can also be purchased separately without having to replace the entire device. Another important indicator that can determine whether or not a device needs to be replaced is the tubing. Stethoscopes can be used as long as they are still in good working order. However, when the ability to hear bodily noises begins to deteriorate, it's time to replace the device.