Sir Thomas Lauder Brunton, 1st Baronet, FRS (14 March 1844 – 16 September 1916) was a British physician who is most-closely associated with the use of amyl nitrite to treat angina pectoris.

He left Edinburgh to work in Austria, the Netherlands, and Germany, returning to University College, London, and while there he was selected for a position at St. Bartholomew's Hospital.

Brunton's clinical use of amyl nitrite to treat angina was inspired by earlier work with the same reagent by Arthur Gamgee and Benjamin Ward Richardson.

Brunton reasoned that the pain and discomfort of angina could be reduced by administering amyl nitrite to open the coronary arteries of patients.

He was appointed a Knight Bachelor in the 1900 New Year Honours list, received the knighthood by Queen Victoria at Osborne House on 9 February 1900,[2] and was made a baronet in 1908.