Feldene drug capsules next to their bottle. Feldene is a brand name for the non-steroidal anti-inflammatory drug (NSAID) piroxicam. It is taken as an analgesic as well as an anti- inflammatory drug. It is thought to work by inhibiting the enzyme cyclo-oxygenase, which synthesises prostaglandin, the molecule that transmits pain signals to the brain. It is used to treat rheumatoid arthritis, backache and gout.