R.I. Gen. Laws § 21-28-3.10: Authorized sales by manufacturers and wholesalers on official written orders.

A duly licensed manufacturer or wholesaler may sell and distribute controlled substances on official written orders to any of the following persons:

(1) To a manufacturer or wholesaler;

(2) To a practitioner;

(3) To a person in charge of a hospital, but only for use by or in that hospital;

(4) To a person in charge of a laboratory, but only for use by or in that laboratory;

(5) To any other person lawfully permitted to possess controlled substances under federal law.