Can antidepressants affect your heart health?

If you’re taking antidepressants, you may have been concerned by recent media coverage claiming that antidepressants can cause increases in blood pressure, cholesterol levels, heart rate and weight, which can raise your risk of heart attack and stroke.

The reports were based on a study in The Lancet that ranked the physical side effects of dozens of different antidepressants, which are prescribed to around 15 per cent of adults in England. 

They are used to help reduce the symptoms of mental health conditions by rebalancing chemicals in the brain. There are several different types that work in slightly different ways. 

The study made headlines because this the first time the physical side effects of different types of antidepressants have been compared.

• Read more about antidepressants 

What did the study investigate? 

The UK researchers reviewed 151 clinical trials and 17 reports from the United States’ Food and Drug Administration involving over 58,000 adults who were treated with one of 30 antidepressants.  

Most trials included in the research were short-term, lasting around 8 weeks. 

The researchers looked at the effect each antidepressant had on a list of health markers, including blood pressure, cholesterol levels, blood sugar levels, heart rhythm, weight and liver and kidney function. 

They compared these effects with a dummy pill (placebo) and then used the results to rank all 30 antidepressants against the health markers. 

The different types of antidepressants included: selective serotonin uptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), tetracyclic antidepressants (TeCAs) and serotonin and noradrenaline reuptake inhibitors (SNRIs). 

What did the study find?

The research shows that different antidepressants have markedly different side effects when it comes to risk factors for cardiovascular disease (CVD) including high blood pressure, high cholesterol, fast heart rate and excess weight. 

For the 6 most prescribed antidepressants in England (see below table), the results showed changes in these risk factors compared to a dummy pill were: 

• Citalopram (SSRI): very small increase in diastolic blood pressure (the bottom number on a blood pressure reading).   
• Sertraline (SSRI): small increase in diastolic blood pressure.
• Amitriptyline (TCA): significant increases in weight and heart rate, plus a small increase in systolic blood pressure (the top number on a blood pressure reading). 
• Mirtazapine (TeCA): significant increase in weight. 
• Fluoxetine (SSRI): significant increase in systolic blood pressure. 
• Venlafaxine (SNRI): significant increases in total cholesterol, blood pressure and heart rate.

Most prescribed antidepressants in England (2024)

Antidepressant	Medicine type	Total items prescribed
Sertraline	SSRI	24,248,772
Amitriptyline	TCA	16,174,611
Citalopram	SSRI	13,352,127
Mirtazapine	TeCA	13,133,620
Fluoxetine	SSRI	7,534, 149
Venlafaxine	SNRI	6,059,811

What did the researchers say? 

The findings show the effect different antidepressants have on CVD risk factors, such as blood pressure, cholesterol, heart rate and weight, varies widely. This is important because many people prescribed antidepressants already live with CVD and these risk factors.  

The researchers illustrate this point with amitriptyline. If taken for 8 weeks, the drug could increase your weight by approximately 1·5 kg, your heart rate by 9 beats per minute, and your systolic blood pressure by 5 mmHg, which could lead to increases in your risk of CVD, heart attack and stroke. 

The researchers say antidepressant treatment guidelines should be updated on the back of the findings so doctors can make sure they’re prescribing the best antidepressant for each person. 

To ensure the results were reliable, the researchers only included randomised controlled trials where antidepressants were the only treatment and they accounted for participants' age, sex, and starting weight. 

However, a large limitation of the study was that the trials only lasted 8 weeks, so it’s not known if the side effects were temporary or lasted over time.

There was also incomplete data on the ethnicity of study participants. In the trials and reports where ethnicity was reported almost 75 per cent were white, which means the findings may not be the same for all ethnic groups.

What did the media say? 

Several UK media outlets covered the study including the BBC and The Independent.

They both correctly reported the findings, including that the study was limited because it only looked at short‑term (about 8 weeks) changes in blood pressure, cholesterol levels, heart rate and weight.

The BHF verdict 

This international study provides important new evidence that antidepressants differ in their physical side-effects, including those that may affect heart health.

It highlights the importance of selecting the right antidepressant for each person and regular monitoring, especially for those with existing CVD and risk factors for it. 

If you're taking antidepressants and have concerns about your heart health do not stop taking it.

Your doctor can help you work out the best antidepressant for you and your heart. 

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