Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 94, § 184A

Upon each package, bottle or other receptacle holding any proprietary or patent medicine, or proprietary or patent food preparation, containing alcohol, morphine, codeine, opium, heroin, chloroform, cannabis indica, chloral hydrate or acetanilide, or any derivative or preparation of any such substance, there shall be a label upon which shall be printed, in type not smaller than eight point (brevier) capitals, a correct statement of the quantity or proportion of each of said substances therein contained; provided, that if the size of the package, bottle or other receptacle will not permit the use of such type, the size thereof may be reduced proportionately. Whoever manufactures, sells, or offers for sale any medicine or food preparation in violation of this section shall be punished by a fine of not less than five nor more than one hundred dollars; but no dealer shall be prosecuted hereunder if the article is marked as it was when purchased by him and he can establish a guaranty signed by the wholesaler, jobber or manufacturer, residing in this commonwealth, from whom he purchases such article, to the effect that the same is correctly marked as required by this section, designating it. Such guaranty, to afford protection, shall contain the names and addresses of the parties making the sale of such articles to such dealer.