Official names have been selected for a number of radicals, counterions and coprecipitated molecules used to form salts and esters of a pharmacologically active species. In most cases, these names represent contractions of the chemical name. Sometimes an official name is associated with 2 or more components, with a 1-word modifier derived for a specific combination of chemical modifications.
The USAN program has created the Organic Radicals, Counterions Used in Coining 2-Word Names (PDF) document to help manufacturers select the appropriate name for their salt or ester.
This list includes terms for common and uncommon radicals and anions. It is not exhaustive and does not include all modifiers used by the USAN Council and other national or international nomenclature groups. Because of the nature of the nomenclature process, new names may be created, if required.