Mr Cameron said Lord McColl had acted in a "perfectly satisfactory" way
Conservative leader David Cameron has defended a shadow health minister for advising a firm which offers customers an alternative to NHS doctors.
Lord McColl is on the advisory board of Endeavour Health, which promises quick and convenient access to a network of "top" private GPs.
Mr Cameron said press coverage claiming it would embarrass the party had been "overwritten".
Mr Cameron has recently defended his party's commitment to the NHS.
This followed criticisms by Conservative MEP Daniel Hannan, who called the service a "60-year mistake" he "wouldn't wish on anyone", claiming it was an overly-bureaucratic hangover of wartime planning which rations care which should be broken up and replaced by a mix of private and state-run provision.
Mr Hannan's remarks were made to media in the US, where a fierce debate is taking place over President Barack Obama's proposed healthcare reforms, although he has stressed they do not reflect official Conservative policy.
Health Secretary Andy Burnham said Mr Hannan's comments reflected the Tories "ambivalence" towards the NHS, but Mr Cameron said the MP had "eccentric views" about some issues and stressed the health service was his party's top priority.
Endeavour, which lists Lord McColl on its website as being on its five-member advisory panel, says it provides "the first comprehensive network of high-quality general practitioners" and dentists in the UK.
Fee-paying members are promised discounted appointments with private doctors, while the company provides a single booking hotline for "top GPs".
But Mr Cameron responded to the story, which first appeared in The Times, by saying Lord McColl had done nothing wrong in becoming involved with Endeavour.
He told GMTV: "He is currently on one of the mercy ships off Africa, carrying out free eye operations for people who otherwise couldn't afford them, and he is a public servant who dedicated a career to the NHS, and now is a spokesman in the House of Lords.
"My understanding is that, yes, he has carried out a couple of consultations for this private company. All of that has been properly declared.
"I think he himself has said that if there is anything improper about what this company has done, he'll sever any contact with it.
"I think that's a perfectly satisfactory state of affairs. I think this story is rather overwritten, if I might say."
He added: "It's not illegal to use private health in Britain, but we want to expand the NHS, and make sure it's as good as it possibly can be, so people don't have to use the private sector."
Lord McColl, a former professor of surgery at London's Guy's Hospital and ex-parliamentary private secretary to Prime Minister John Major, has been a shadow health minister since 1997.