The markings on a white oblong pill or any pill or capsule sold over the counter or by prescription are the medication's imprint, reports GoodRx. The imprint is required on such medication in the United States, and it is used to identify the medication. If the pill does not have marking on it, then it is likely a vitamin or some other type of supplement.
There are other methods that are used in combination with the imprint to make it easier for health professionals and patients to identify medication, explains RxList. The imprint code is commonly composed of letters or numbers stamped into or printed on the pill or capsule. The second identification factor is the shape and size, if the medication is in pill form. The third identifying factor is the color of the pill or capsule. Such precise identification helps prevent patients from taking the wrong medication and possibly causing severe reactions or more serious harm.
Pill identifying tools are available online for such medication identification, such as the one offered at RxList. A user enters the imprint code and selects the shape of the pill and color of the pill or capsule from a drop-down menu, and the tool conducts a search of medications that matches the criteria. Individuals should consult a health care professional with any doubts about the type of medication they are taking.