In the United States, companies that manufacture medicines are required to publish certain kinds of information about each product. This document is commonly known as a “package insert” because it is usually included with each package of the medicine.

You can also read these documents (also called “prescribing information”) online for brand-name medicines. Package inserts for Dilantin, the brand-name version of phenytoin, are available in PDF format:
Capsules: http://www.pfizer.com/download/uspi_dilantin_kapseals.pdf
Liquid: http://www.pfizer.com/download/uspi_dilantin125.pdf

The information about the specific appearance of the capsules and a few other items will be different for generic phenytoin, but most things should be the same. Some content also may differ in other countries.

To learn how to read and understand a package insert, see “How to read a package insert.”