Side effects of different antidepressants have been ranked for the first time, revealing huge differences between drugs, El.kz cites BBC.
Academics looked at the impact medications had on patients in the first eight weeks after starting treatment, with some causing patients to gain up to 2kg in weight or vary heart rate by as much as 21 beats every minute.
The researchers say up to one-in-six adults in Europe and North America take antidepressants.
They warned the gulf in side effects could affect people's health and whether they could stick to their prescription.
They said nobody reading this should stop their treatment, but have called for antidepressants to be closely matched to the needs of each person.
"There are big differences between [antidepressants] and this is important not just for individual patients, but large numbers of people are taking them, so even modest changes could have a big effect across the whole population," said researcher Prof Oliver Howes.
We've always known antidepressants affect physical health. The study by King's College London and the University of Oxford is the first to produce a ranking so the effects of medicines can be easily compared.
The team analysed 151 studies of 30 drugs commonly used in depression, involving more than 58,500 patients.
"Clearly no two antidepressants are built the same," said Dr Atheeshaan Arumuham, from King's College London.
Those differences can stack up in ways that become clinically important, including an increased risk of heart attack or stroke.
It means even people with the same diagnosis could be better suited to different antidepressants depending on their own preferences and other health conditions.
Dr Toby Pillinger told BBC Radio 4's Today programme: "The majority of the studies we looked at were relatively short. We're looking at eight weeks' duration and still within that duration we were seeing large changes in physical health parameters which we would argue have clinical relevance.
"The last thing I want is for this story to be scaring people," he added.
"I want to see this as empowering individuals to take the initiative and to engage in shared decision-making with their practitioner."