This is a list of methylphenidate analogues, or Phenidates. The most well known compound from this family, methylphenidate, is widely prescribed around the world for the treatment of attention deficit hyperactivity disorder (ADHD) and certain other indications. Several other derivatives including rimiterol, phacetoperane and pipradrol also have more limited medical application. A rather larger number of these compounds have been sold in recent years as designer drugs, either as quasi-legal substitutes for illicit stimulants such as methamphetamine or cocaine, or as purported "study drugs" or nootropics.