Root beer has a come a long way since it was first bottled and sold to the public in 1893. Nowadays there are more alternatives to the soda. The best way to find an alternative is to assess the ingredients in root beer -- sassafras, vanilla, sarsaparilla root, licorice root, and nutmeg -- then find a drink option that may include one or more of these ingredients.
Due to its high vanilla content, cream soda -- also known as vanilla soda -- is a comparable alternative to root beer. Cream soda was first sold to the public around the same time as root beer and got its name from the term "ice cream soda," scoops of ice cream served in glasses of soda pop, much like a root beer float. Most cream sodas include food coloring to look like root beer, but some brands also come clear.
Sarsaparilla, a specialty soda popular in the Old West, is one of the closest alternatives you may find to root beer. Sarsaparilla soda is not currently sold nationwide by any major soft-drink manufacturers, but these companies still sell sarsaparilla base to local soda makers and bottlers. Local convenience stores and supermarkets are a good place to look for this drink. Sarsaparilla soda's main ingredient is sarsaparilla root extract.
The main ingredient in sassafras soda used to be the sassafras root, which was also what gave root beer its characteristic "root" flavor. In the 1960s, though, the FDA banned the sale of sassafras after deeming a certain chemical in it, Safrole, as cancer-causing. These days sassafras soda is still made but its sassafras root flavor has been replaced with licorice root and wintergreen -- both also found as the replacement for sassafras in root beer.
Dr Pepper has a high vanilla extract content that makes it comparable to root beer, which is also high in vanilla. Dr Pepper is easiest to find compared with other root beer alternatives, as the soda is sold nationwide at supermarket chains, restaurants and chain convenience stores.