A major medical defence union has warned GPs they could face legal action if they put patients at risk by failing to thoroughly investigate their requests to online pharmacies for weight loss medications.

The Medical Defence Union (MDU), which provides legal support to 200,000 doctors, nurses, dentists and other healthcare workers in the UK, said GPs must have “a robust system in place to gather relevant information before a prescription is provided.”

The MDU issued its guidance having been contacted by GPs who are unsure what to do when contacted by an online pharmacy for a patient’s information to check if there is anything in their medical history that makes the prescription inappropriate.

The MDU’s medico-legal adviser Dr Ellie Mein said GPs have faced “a dilemma” over whether they can take a pharmacy’s word that a patient has consented to their information being shared or if a patient has “misrepresented their BMI or medical history to the pharmacy.”

She said: “GPs have an ethical duty to share accurate and up-to-date information with those providing patient care.” However, Dr Mein insisted GPs need to communicate with patients as well as online pharmacies.

“Our advice is that if it becomes clear there may be a risk to the patient in receiving the medication, GPs will need to discuss this with the patient and check if they agree to this being shared with the pharmacy,” she said.

“If the patient objects, GPs will need to explain this to the pharmacy and it will then be for the pharmacy to consider whether the prescription is appropriate.”

Dr Mein said although investigations place “an additional burden on GP practices at a time when they are already under strain,” they were necessary to protect patients and avoid potential legal action.

“If there isn't a robust system in place to gather relevant information before a prescription is provided, patients could be at risk and prescribers vulnerable to criticism and medico-legal investigations,” she said.