McIntyre was in charge of a major campaign of diphtheria immunisation directed at Paisley's schoolchildren, visiting every school in the area to persuade the children and their parents to get themselves vaccinated against the lethal disease.
[1] Robert McIntyre then took up a position under Glasgow Corporation's Department of Health as Port Boarding Medical Officer, based at Greenock.
[1][2] This involved his being part of a team which had the responsibility of ensuring that ships were free of infections before they proceeded up the River Clyde to Glasgow, and also liaising with the vessels' medical staff.
[1][2] With the creation of the National Health Service in 1948, McIntyre was appointed as Consultant Chest Physician at Stirling Royal Infirmary.
On 13 April 1945, shortly before the end of World War II, McIntyre won the Motherwell by-election, with a narrow majority of 617 votes over his Labour opponent.
Two reluctant sponsors were found but McIntyre chose to present himself to the Speaker alone, later writing "I very clearly stated to the people of Motherwell and Wishaw that I would give no allegiance to the London-controlled parties".
A vote to waive the rule was lost, and eventually he accepted the sponsorship of James Barr and Alexander Sloan "under protest".
In 1962 he was nominated by the Scottish Nationalist Association as a candidate for Rector of the University of Glasgow,[6] where he finished second behind Albert Luthuli who was then the President of the African National Congress.