There is no way to positively identify it, other than to pay to have it lab tested. All prescription meds sold in the US are required to have unique markings for ID, however it could be anything else, drugs sold OTC, Vitamins, herbal supplements or etc. These are not regulated and have no required markings.
verwon@gmail.com
My information is not guaranteed correct. I do not get them right all the time, but I do enjoy the hunt~