NHS Direct has been heavily criticised by some health workers for needlessly referring patients with minor problems to GPs and emergency services.
Doctors and ambulance crews said giving urgent referrals to people with issues such as sprains and high temperatures is putting a strain on the system.
The service handles about 500,000 calls a month, and is said to be looking to deal with more patients in-house.
Currently around 34% are dealt with by NHS Direct, just short of government targets.
Another 34% are apparently told to contact other services such as dentists, GPs, pharmacies or walk-in centres.
A further 32% of patients are referred as urgent or emergency cases and are told to see a GP immediately or sent to hospital - in line with government targets.
But Dr Mark Reynolds, GP out-of-hours spokesman for the NHS Alliance and a member of the government's advisory group which oversaw the formation of 24-hour phone service, said the targets are too lenient.
He said: "NHS Direct is too cautious. They refer patients on as urgent or emergency when doctors doing out-of-hours or in A and E would not recognise them as such.
"We have had things like moderate temperatures or diarrhoea and vomiting referred as urgent.
"It puts strain on the system as it means we have to see the patients quickly, which could be a risk to patients who are real emergencies."
A Department of Health spokeswoman said: "NHS Direct will continue to work to ensure that only appropriate callers are referred, but it is important that patient safety is not compromised."