A powerful fat busting drug is now available over the counter in Bradford, raising fears amongst GPs it could be abused.

Obese patients wanting to lose weight using Xenical previously needed a doctor's prescription for the drug but now they can visit Boots in Forster Square.

The branch is one of 100 around the country offering the drug which inhibits the absorption of fat in the intestine so the body excretes it instead.

Users of the drug must stick to a low-fat diet or face unpleasant side effects, including loss of bowel control.

Dr John Givens, secretary of Bradford Local Medical Committee, a body which represents local GPs, said while pharmacists were perfectly competent to administer and dispense drugs, he did have worries about the scheme.

"I have concerns this relies on the patient being honest with the pharmacist," he said.

"Someone who is very keen to get this drug might conceal other medical conditions or medication.

"If a person was to go to their GP they would be aware of everything the person had been prescribed in the past."

And Dr Jim Kennedy, chairman of the Royal College of GPs prescribing committee, said he had "substantial concerns".

"We have particular concerns about the treatment of conditions such as obesity with drugs because it has to be a very holistic approach and drugs would only be one very minor part of that," he said.

"We would be worried about how the pharmacists would know about the background of the patient and how they would stop people being able to get two or three times the normal amount by simply going to several stores."

A spokesman for Boots said the programme would follow a strict protocol and was only suitable for obese adults who needed to achieve significant weight loss.

The company's computer system would prevent customers obtaining more than one prescription from different branches.

To enrol on the programme patients will need a consultation with the pharmacist, who will assess their body mass index (BMI) and check if they are suitable for the medicine.

Blood pressure and glucose levels will also be taken. If the patient meets the criteria then the pharmacist will explain how to use the drug to best effect. Patients will also be given advice on exercise and nutrition and their GP will be contacted to update their medical records.

Boots assistant pharmacy superintendent Steve Churton said: "People often don't like going to their GPs about weight loss.

"By having this programme available through consultation with a pharmacist we are making it more accessible for those who want to try this effective approach to losing weight."

Sheila Webb, Director of Public Health for Bradford City Teaching Primary Care Trust, said: "Pharmacists are highly skilled health professionals who have the professional ability to advise people about weight management in general and, for certain people, about the specific use of Xenical."