The historic archives come from a collection of records covering more than 100 hospitals and health organisations across the region from as early as 1739.
NHS Grampian archivist Fiona Musk oversees the collection and says the well-preserved documents, which are thought to be some of the most comprehensive in the country, provide fascinating reading.
"Not only do we see why people were admitted, but the treatment they received, and the spread of epidemics such as measles."
Grampian patients admitted for mental health care were split into two categories - physical and moral.
"The physical reasons for admission included old age, head injuries and intemperance. "While the moral reasons included anxiety, death of relatives and disappointment in love."
Some of the first finance reports for the health board reveal the treatments used back in the 19th century.
"We can see from these records that the hospital budget was used to purchase brandy and whisky, which was often given to patients as part of treatment."
Sifting through thousands of the records, which are kept at the Sir Duncan Rice Library, Fiona has noted a few memorable cases.