Several. Glucosamine, chondroitin, msm, but particularly glucosamine, for which studies have been conducted in places like cleveland clinic.
Arthritis. Here are some options to consider: bladderwrack, wild yams, horsetail, meadowsweet, devil's claw and witch hazel bark. There are several others. Research the best choice for you based on the unique pharmacological properties of these botanicals. Many have anti-inflammatory effects. Some are applied as a liniment, others ingested by infusion or plant extracts.