Sarsaparilla is a tropical vine whose root has been used for centuries to make beverages, tonics, and herbal remedies. The plant belongs to the Smilax genus, a group of roughly 350 species of climbing vines found in tropical and subtropical regions across the Americas, Asia, and parts of Europe. If you’ve heard the word in old Western movies or spotted it on a bottle at a specialty soda shop, you’re encountering the legacy of a plant that was once considered serious medicine and remains a popular flavoring today.
The Plant Itself
Sarsaparilla vines are woody, perennial climbers that grow from thick, tuberous underground stems called rhizomes. The roots extending from these rhizomes are long, thin, and fibrous, and they’re the part that gets harvested. The vines themselves can be prickly, with alternating leaves and small tendrils that help the plant grip and climb through forest canopy. Several species have been used commercially, but the most commonly referenced are Smilax officinalis, Smilax regelii, and Smilax glabra, native to Central America, South America, and Southeast Asia respectively.
The root is where the action is. It contains steroidal compounds called saponins, which give it a slightly bitter, earthy flavor and a natural foaming quality when mixed with water. It also contains flavonoids, including quercetin, a compound found in many fruits and vegetables that plays a role in reducing inflammation. These steroidal saponins were historically significant enough that sarsaparilla root was used in the partial synthesis of cortisone and other steroid hormones in early pharmaceutical manufacturing.
How It Was Used in Traditional Medicine
Sarsaparilla has a long history as a medicinal plant, particularly in Central America and Southeast Asia. Spanish explorers brought it back to Europe in the 1500s, where it quickly gained a reputation as a treatment for syphilis. For the next several centuries, it was marketed as a “blood purifier,” prescribed for skin diseases, joint pain, and gout. In Southeast Asia, herbal mixtures containing sarsaparilla root have been used to treat dermatitis, syphilis, and gouty arthritis for generations.
By the 19th century, sarsaparilla was one of the most widely sold patent medicines in America. Druggists sold it as a general tonic, often in syrup form, claiming it could cure everything from fatigue to chronic illness. While much of this was marketing exaggeration typical of the era, the plant’s anti-inflammatory compounds do have some biological basis. Lab studies on certain Smilax species have shown they can reduce inflammatory signaling molecules by meaningful amounts, with one study finding that flavonoids in sarsaparilla reduced a key inflammation pathway by about 62%. Some species have also shown the ability to modulate immune responses in animal and tissue culture studies, particularly in models of psoriasis and rheumatoid arthritis.
That said, human clinical trials on sarsaparilla are essentially nonexistent. No rigorous study has confirmed that taking sarsaparilla supplements produces reliable health benefits in people. The gap between “this shows activity in a lab dish” and “this works as medicine” remains wide.
Sarsaparilla as a Drink
The flavor most people associate with sarsaparilla is a slightly sweet, earthy, vanilla-adjacent taste with a mild bitterness. Traditional sarsaparilla soda was made by simmering dried sarsaparilla root in water along with sassafras root bark, raisins for sweetness, and sugar, then fermenting it lightly with a small amount of ale yeast to create natural carbonation. The result was a mildly fizzy, dark, aromatic drink that became a staple of saloons and soda fountains in 19th century America.
Today, sarsaparilla soda is still produced commercially, especially in Australia, the Philippines, and parts of Central America, though many modern versions use artificial flavoring rather than actual root extract. You can find authentic sarsaparilla root (dried and chopped) through herbal suppliers if you want to brew your own.
Sarsaparilla vs. Root Beer
People often use “sarsaparilla” and “root beer” interchangeably, but they come from different plants. Root beer was traditionally made from the bark and root of the sassafras tree, which has a distinctive aroma you’d recognize instantly. Sarsaparilla comes from a vine, not a tree, and has a different, somewhat earthier flavor profile. In practice, many old recipes blended both ingredients together, which is why the two drinks are so closely linked in people’s minds. Modern root beer typically uses neither plant, relying instead on artificial sassafras flavoring (the natural version contains safrole, which was banned as a food additive by the FDA in the 1960s).
Safety and Side Effects
Sarsaparilla is generally well tolerated. The most common side effect is stomach irritation, which typically resolves after stopping use. There are no well-documented toxic effects at normal dietary or supplement doses.
The more important concern is potential drug interactions. Animal studies suggest sarsaparilla may increase absorption of digoxin (a heart medication), amplify the effects of diuretics, and reduce blood levels of methotrexate (used for autoimmune conditions and certain cancers). Whether these interactions hold true in humans hasn’t been confirmed, but the possibility is worth noting if you take any of these medications. There is also no safety data for pregnant or breastfeeding people, so most sources recommend avoiding it during those times.
Sarsaparilla supplements are sold as capsules, powders, teas, and liquid extracts. Because the supplement industry is not tightly regulated, the actual sarsaparilla content in these products varies widely. Some products labeled “sarsaparilla” contain Indian sarsaparilla (Hemidesmus indicus), which is a completely different plant from a different botanical family, so checking the species on the label matters if you care about getting the real thing.