Mass. Gen. Laws ch. 94C § 5
Controlled substances which are excepted pursuant to section four may be dispensed, or sold at retail, except that the exception authorized by this section shall be subject to the following conditions: (1) that such preparation shall be dispensed, or sold in good faith as a medicine, and not for the purpose of evading the provisions of the controlled substances law; (2) that the purchaser of such preparation identify himself to the satisfaction of the pharmacist; and (3) that of such preparation not more than four ounces are dispensed, or sold to a person during any 48 hour period.
The pharmacist dispensing such excepted substances shall keep an accurate record book including the name and address of the purchaser, the name of the preparation, the strength per dosage unit, the quantity dispensed and the date.
Mass. Gen. Laws ch. 94C, § 5