In a groundbreaking study, researchers have ranked the side effects of antidepressants for the first time, highlighting significant differences among various medications. This research is particularly relevant for the approximately eight million individuals in the UK who currently rely on these drugs for managing depression. The study focused on the impact of antidepressants during the first eight weeks of treatment, revealing that some medications can lead to substantial weight gain or fluctuations in heart rate.
The research team, comprising experts from King's College London and the University of Oxford, analyzed data from 151 studies involving over 58,500 patients. The findings, published in the Lancet medical journal, indicate that not all antidepressants are created equal, demonstrating noteworthy differences in their physical health impacts.
On average, the study results revealed:
An eight-week prescription of agomelatine resulted in a 2.4kg weight loss, while maprotiline caused nearly 2kg of weight gain. A difference of 21 beats per minute in heart rate was observed between fluvoxamine, which slowed the heart rate, and nortriptyline, which increased it. Blood pressure differences were significant, with an 11 mmHg variation between nortriptyline and doxepin.These findings underscore the importance of tailoring antidepressant prescriptions to individual health profiles, as the same diagnosis may lead to different treatment responses based on personal health conditions.
In a hypothetical scenario featuring three patients—Sarah, 32; John, 44; and Jane, 56—each diagnosed with depression but with different health priorities, it becomes clear how varied antidepressant recommendations can be. Sarah wishes to avoid weight gain, John needs to manage his high blood pressure, and Jane is concerned about her cholesterol levels.
Dr. Toby Pillinger advises that:
Sarah should consider antidepressants that minimize weight gain, such as agomelatine, sertraline, or venlafaxine, rather than amitriptyline or mirtazapine. John should avoid medications like venlafaxine, amitriptyline, or nortriptyline that may elevate his blood pressure and opt for citalopram, escitalopram, or paroxetine. For Jane, it would be advisable to steer clear of venlafaxine, duloxetine, and paroxetine, which are linked to increased cholesterol, and consider citalopram or escitalopram instead.The researchers emphasize that it is overly simplistic to categorize antidepressants as merely "good" or "bad." For example, while amitriptyline may lead to weight gain, it also provides benefits in managing pain and sleep issues. Notably, the most commonly prescribed class of antidepressants, SSRIs (selective serotonin reuptake inhibitors) like paroxetine, citalopram, escitalopram, and sertraline, generally exhibit fewer physical side effects.
Interestingly, fluoxetine, also known as Prozac, showed a correlation with weight loss and elevated blood pressure in this study. Prof. Andrea Cipriani from the University of Oxford remarked that it remains uncertain how many of the millions of patients currently prescribed antidepressants may benefit from a different medication.
The push for more generic and affordable medications has led to 85% of antidepressant prescriptions in the UK being concentrated on just three drugs: citalopram, sertraline, and fluoxetine. Implementing the findings from this recent study could significantly diversify treatment options and improve patient outcomes.
To aid in this effort, researchers are developing a free online tool designed to help both doctors and patients identify the most suitable drug based on individual needs. However, they acknowledge that such changes would require a substantial cultural shift within the NHS.
It’s important to note that the study primarily evaluated the initial eight weeks of treatment, and while complementary data suggests that these short-term changes may persist, further research is necessary to confirm long-term outcomes. Dr. Prasad Nishtala from the University of Bath, who was not involved in the study, recognizes the novelty and significance of these findings, especially considering the cumulative risks associated with long-term antidepressant use in real-world settings.
