A major UK study has found that antidepressants can cause widely differing physical side-effects, including changes in weight, heart rate, and blood pressure, depending on the medication.
Researchers from King’s College London and the University of Oxford analysed data from 151 clinical studies involving more than 58,000 people, comparing the effects of 30 commonly prescribed antidepressants.
They discovered weight changes of up to 4kg between some drugs, even within just eight weeks of use. For example, patients on maprotiline gained around 2kg, while those on agomelatine lost roughly 2.5kg. Nearly half of people taking maprotiline or amitriptyline gained weight, while more than half on agomelatine experienced weight loss.
The review also found a 21-beat-per-minute difference in heart rate between fluvoxamine and nortriptyline users, and an 11 mmHg variation in blood pressure between nortriptyline and doxepin.
Dr Toby Pillinger of King’s College London said that while antidepressants help millions, “some can lead to meaningful changes in weight, heart rate, and blood pressure in a relatively short period.” He added that SSRIs, the most widely prescribed antidepressants, generally have fewer physical side-effects.
Professor Andrea Cipriani from Oxford University said the findings highlight the need for shared decision-making between patients and clinicians, ensuring treatments are tailored to individual health needs and preferences.
