The commissioner acting jointly with the board of registration in pharmacy may by regulation pursuant to the provisions of chapter thirty A except any compound, mixture or preparation containing any substances in paragraph (a) or (b) of Schedule III or in Schedule IV, V or VI established pursuant to the provisions of section two from the application of all or any part of this chapter if
Such regulation shall state the weight of the controlled substance per fluid ounce, or if a solid or semi-solid preparation the weight in the avoirdupois amounts, and if the metric system is used, the weight in grams per hundred cubic centimeters in the case of a fluid, or the weight per gram in the case of a solid or semi-solid preparation.
The commissioner shall by regulation modify, rescind or revoke an exception whenever it has been modified, rescinded or revoked under the provisions of the Federal Comprehensive Drug Abuse, Prevention and Control Act of 1970 or any amendment thereof.
Mass. Gen. Laws ch. 94C, § 4