Here is what they say on the Dept of Revenue site...

"Are sales of "Medical Marijuana" subject to sales tax?
In the state of Washington, sales of medical marijuana are retail sales. As such, the selling price is subject to retail sales tax. In addition, the seller is subject to the business and occupation (B&O) tax under the retailing classification. This is true even if it is sold by a medical marijuana dispensary.

Sales of medical marijuana are not eligible for the retail sales tax exemption provided for prescription drugs. RCW 82.08.0281 provides an exemption from retail sales tax for certain drugs, but only when prescribed as authorized by the laws of this state. However, marijuana is a Schedule I controlled substance and cannot be prescribed under either federal or state law in Washington.

Chapter 69.51A RCW addresses medical marijuana, but does not authorize the prescription of medical marijuana. This chapter specifically avoids authorization of a prescription by referring to ā??valid documentationā?, which does not equate with a prescription as defined in RCW 82.08.0281(4)(a), or as provided in RCW 69.50.308 (Prescriptions). Chapter 69.51A provides that it is only intended to protect qualifying patients, designated providers, and physicians from liability, prosecution, or criminal guilt when marijuana is possessed, used, provided or authorized."
hiamps Reviewed by hiamps on . AP exclusive Now this is a good one. Far out...but wait, doesn't the State also state that dispensaries are illegal? Now I do not know where the exact clause is, but on the DOH website in FAQ the following: From: Medical Marijuana Frequently Asked Questions - Washington State Dept of Health fricking oxymoronic crap. Lawyer fuel. Rating: 5