Howson was born in London but moved to Ayrshire as a young child. He attended the Glasgow School of Art and came to prominence in the 1980s as part of the New Glasgow Boys movement. He specialises in dramatic figurative work that uses line and colour in an expressive and powerful manner. His portrayals of Glasgow's down-and-outs gained him a vast amount of public and media attention which resulted in his work being bought by the world's most leading galleries and collected by a starry list of private clients including Madonna and David Bowie.

In 1993 Howson was appointed the Official British War Artist for Bosnia, his inevitably bleak work provoking controversy when it was subsequently exhibited. His Balkan experiences brought to a head a series of problems that had been developing in his personal life and both his physical and mental health suffered. However, he has recently returned to form with a new collection of paintings, including two nude studies of Madonna which sparked considerable interest.