Diclofenac is an NSAID or Nonsteroidal Anti-Inflammatory Drug used to decrease inflammation and also as an analgesic (pain killer) in certain conditions. It is delivered as such or supplied in medications under different trade names.

Diclofenac is a name derived from the drug’s chemical name which is 2-(2,6-dichloranilino) phenylacetic acid. This medicine was synthesised for the first time by Rudolf Pfister and Alfred Sallman and sold as Voltaren by the pharmaceutical company Ciba-Geigy (now called Novartis) in the year 1973. In India, UK, USA and Brazil, the drug is supplied either as the potassium salt or as the sodium salt. It is mostly sold as the sodium salt in China. In some countries, only the potassium salt is supplied.