WebMD, Drugs.com and Healthline all operate search engines to identify pills using by a combination of shape, color and imprint. Pills sold in the United States are legally required to be uniquely identifiable unless exempted, according to the U.S. Code of Federal Regulations.
Tablets, capsules and other pills must be imprinted with information that allows drugs and their dosages to be identified through a combination of pill color, shape and imprint, according to the CFR. The law expresses a preference for letter and number imprints over logos or other symbols.
Marking requirements apply to both over-the-counter and prescription pills, reports Drugs.com. Unmarked pills may contain illegal drugs, foreign drugs, or benign vitamins or candy. The Food and Drug Administration considers drugs without markings to be misbranded, unapproved or altered. Drugs without marking may also predate the requirement for imprints, which was first established in 1993.
Homeopathic pills only need to indicate that they contain homeopathic remedies and their manufacturer, states the CFR. Drugs like radiopharmaceuticals, pharmacist-compounded drugs and some drugs only administered by health care professionals are exempt from the imprint requirements. If applying markings to a drug is not feasible, a drug manufacturer can request the FDA for an exemption from marking requirements.