The British drug maker GlaxoSmithKline will no longer pay doctors to promote its products and will stop tying compensation of sales representatives to the number of prescriptions doctors write, its chief executive said Monday, effectively ending two common industry practices that critics have long assailed as troublesome conflicts of interest.

The announcement appears to be a first for a major drug company — although others may be considering similar moves — and it comes at a particularly sensitive time for Glaxo. It is the subject of a bribery investigation in China, where authorities contend the company funneled illegal payments to doctors and government officials in an effort to lift drug sales.

Andrew Witty, Glaxo’s chief executive, said in a telephone interview Monday that its proposed changes were unrelated to the investigation in China, and were part of a yearslong effort “to try and make sure we stay in step with how the world is changing,” he said. “We keep asking ourselves, are there different ways, more effective ways of operating than perhaps the ways we as an industry have been operating over the last 30, 40 years?”

For decades, pharmaceutical companies have paid doctors to speak on their behalf at conferences and other meetings of medical professionals, on the assumption that the doctors are most likely to value the advice of trusted peers.