Thomas John MacLagan

Thomas Maclagan (1838–1903) was a doctor and pharmacologist from Dundee.

He was medical superintendent at the city's Royal Infirmary from 1864 to 1866, during which time he had to cope with a major fever epidemic and became noted for pioneering the clinical use of thermometers.

He carried out research into the effect of salicin, an extract from willow bark and a known anti-rheumatic treatment. This work was followed by Carl Thiersch, and in 1874 salicylic acid was synthesised, the active ingredient in Asperin.

He later established a practice in London and treated patients like Thomas Carlyle and the royal family.