Warning as drugs fuel epidemic of obesity
GPs could face legal problems if they fail to discuss weight gain lists
A series of commonly used medications actively promote weight gain and are contributing to the UK's obesity epidemic, researchers have warned.
Millions of patients are taking obesogenic drugs for conditions including epilepsy and diabetes which are causing weight gains of up to 10kg a year, their study found.
Some patients on antipsychotics are putting on so much weight they are abandoning drug treatment, yet the potential for weight gain is poorly reported in the literature, the authors claimed.
The systematic review of 43 studies, involving 25,663 patients, found the antipsychotics clozapine and olanzapine were responsible for the greatest average weight gains, at 9.9kg over a year and 7.1kg over just 12 weeks.
Insulin in type 2 diabetes raised weight by an average of 6.6kg and valproate for epilepsy by 5.8kg, according to the study, published online by medical journal QJM.
The University of Glasgow researchers warned GPs could face medicolegal problems if they failed to discuss potential weight gain with patients before prescribing.
Study leader Wilma Leslie, a research nurse in human nutrition at the university, said: 'Given the common and long-term use of many of these drugs it is likely they play a significant contributory role in the increasing prevalence of obesity.'She added: 'The potential of weight gain should be discussed with patients prior to institution of therapy, both on medicolegal grounds and to ensure weight maintenance is promoted and adhered to.'
Dr Frankie Phillips, a dietician with the British Dietetics Association, said GPs should weigh up the risks and benefits of drug treatment with individual patients.
'If somebody is taking a drug long term which can lead to weight increase they need to be made aware of that by their GP and informed about strategies to prevent that.'
Dr Phillips said patients could be referred to a dietician for advice and their weight monitored by practice nurses.
Dr Jim Kennedy, prescribing spokesman for the RCGP, said he was sceptical that drug use was a significant contributor to obesity, but that GPs should take the effects of drugs into account in patients with specific risk factors, such as family history and poor diet.