Five professional people, including three physicians, an engineer, and an accountant, reported severe changes in mental acuity, including lack of concentrating ability, amnesia-like episodes, difficulty in simple calculations, and problems in reading. Each was taking methyldopa at normal dosages, and when treatment with this drug was discontinued the mental symptoms disappeared within 96 hours. These cases emphasize the importance of questioning patients taking methyldopa about difficulties in mentation. ( JAMA 230:1428-1429, 1974)