Glucose monitoring sensors

Sales tax does not apply to single use glucose monitoring sensors that are prescribed by a licensed health care provider.

Glucose monitoring sensors contain a coating of an enzyme that reacts with the user’s blood to diagnose glucose levels. The user must replace the disposable sensors every 2-3 days once the drug runs out.
 
Therefore, these sensors qualify for the sales tax exemption available to “Disposable medical devices used to deliver prescription drugs.” 

References

RCW 82.08.935 - Exemptions—Disposable devices used to deliver prescription drugs for human use.

WAC 458-20-18801 - Medical substances, devices, and supplies for humans—Drugs prescribed for human use—Medically prescribed oxygen—Prosthetic devices—Mobility enhancing equipment—Durable medical equipment.