Washington Revised Code Title 69. Food, Drugs, Cosmetics, and Poisons § 69.41.040. Prescription requirements--Penalty

(1) A prescription, in order to be effective in legalizing the possession of legend drugs, must be issued for a legitimate medical purpose by one authorized to prescribe the use of such legend drugs. Except as provided in RCW 69.41.095, an order purporting to be a prescription issued to a drug abuser or habitual user of legend drugs, not in the course of professional treatment, is not a prescription within the meaning and intent of this section; and the person who knows or should know that he or she is filling such an order, as well as the person issuing it, may be charged with violation of this chapter. A legitimate medical purpose shall include use in the course of a bona fide research program in conjunction with a hospital or university.

(2) A violation of this section is a class B felony punishable according to chapter 9A.20 RCW.