New antidepressant warning – the longer pills are taken the bigger the risk of often-overlooked condition

Long-term users of antidepressants are 10-times more likely to suffer severe withdrawal symptoms when coming off the drugs, a study suggests.

Antidepressants are one of the most commonly prescribed medications in the UK, with about one in seven people now using the powerful mood-altering drugs.

But University College London (UCL) researchers found the longer a patient uses them the more likely they are to suffer from little-known withdrawal symptoms as they come off.

Experts also found long-term users had a higher risk of these withdrawal symptoms being severe and of experiencing them for longer.

While some of these symptoms could be attributed to the depression the drugs are designed to treat returning, many were physical problems like dizziness, headaches and nausea. 

The researchers said their findings were concerning given how approximately half of Britons who take antidepressants do so for at least a year, with the figure being even higher in the US. 

Some patients are known to have been taking the drugs for at least half a decade. 

It also adds to a growing level of concern regarding extended use of antidepressants, with previous studies linking them to heart problems in young people alongside long-term and even permanent sexual dysfunction.

However, independent experts warned that the study’s findings should be treated with caution.

All experts have advised patients using antidepressants to not stop taking their medication before discussing options with their medical team. 

Publishing their findings in the journal Psychiatry Research, the team found 64 per cent of patients who had taken antidepressants for at least two years suffered moderate to severe withdrawal symptoms once they tried to stop.

In contrast, 73 per cent of people who had been using the drugs for six months or less experienced either no or only mild withdrawal symptoms when coming off the medication.

The researchers said this meant a patient taking antidepressants for at least two years or more was 10-times more likely to experience withdrawal problems compared to patients only taking the drugs for six months. 

Across the study group, one in six patients reported suffering a severe withdrawal symptom.

Almost a third of long-term users also reported withdrawal symptoms lasting longer than three months, with about one in 10 having these last for over a year.

For short term users, only a tenth reported withdrawal problems lasting longer than three months.

While many of the reported symptoms could be due to problems linked to depression and anxiety 76 per cent of patients experienced physical problems like dizziness, headache, vertigo, or nausea. 

Almost half of patients who reported symptoms experienced four or more of these physical side effects.

There are also fears withdrawal symptoms are so severe they stopped patients from coming off the drugs. 

Across the study group, 38 per cent of patients said they were unable to stop taking antidepressants when they tried to do so.

This rose to 79 per cent among people taking them for over two years.  

Dr Mark Horowitz, an expert in psychiatry and lead author of the new study, has previously warned about a lack of research on how to safely get patients off antidepressants.

Speaking today, he said the findings supported the idea that patients should only be given the drugs for the shortest possible time.

‘This is one reason to use antidepressants for no longer than necessary – because doing so may make it harder to stop using them later on,’ he said.

World-renowned UCL psychiatrist Professor Joanna Moncrieff, senior author of the paper and another expert concerned about extended antidepressant use, said patients should consult their medical team before coming off the drugs. 

‘Withdrawal symptoms are commonly experienced by people coming off antidepressants, so we would advise that people who want to stop taking the medication should do so in consultation with an informed health professional,’ she said. 

The study was based off a small group of 310 patients who responded to a survey.

Most—62 per cent—said antidepressants had been helpful to them. 

The authors noted a limitation of their study was, because it was survey, patients who had experienced withdrawal symptoms may have been more motivated to respond to these questions,  which could have influenced the results. 

Independent experts have urged caution over interpreting the new findings. 

Dr Gemma Lewis, an expert in psychiatric epidemiology at UCL, said: ‘This type of study is highly susceptible to bias and the findings should not be used to inform practice.’ 

‘The number of people included in the study was very small, compared to the number of people who use this NHS service.

‘These types of studies are at a much higher risk of bias than studies which use larger samples, follow people over time, and have a control group.’

Professor Anthony Kendrick, and expert in primary care at University of Southampton, was another who urged caution. 

‘The percentage of people reporting severe withdrawal symptoms of 15 per cent is likely to be an overestimate,’ he said. 

He added the nature of survey could also have influenced the results: ‘Giving people a list of symptoms to choose from elicits a greater number than asking them to report symptoms themselves, spontaneously.’ 

Reacting to the study a spokesperson for the Royal College of Psychiatrists said antidepressants are an effective option for many patients. 

However, they added that long-term use of the drugs should only be considered for serious cases involving recurrent depression and this should be reviewed regularly. 

‘Most people will be able to stop taking antidepressants without significant difficulty by reducing the dose, known as “tapering”, over a few weeks or months. 

‘Some people can experience withdrawal symptoms that last longer and may be more severe, particularly when the medication is stopped suddenly. 

‘Ultimately, the use of antidepressants, should always be a shared decision between a patient and their doctor based on clinical need and the preferences of the patient.

Until 2019, NHS guidance on antidepressant withdrawal symptoms stated this was mostly a mild and short-lived problem–lasting no more than about a week.

Now NHS guidance acknowledges that it can be severe for some patients and can last many months.

The authors of new paper said their survey didn’t have enough data to show if tapering could help patients coming off antidepressants experience fewer and milder symptoms. 

As such they said this was an area in need of further research. 

Antidepressants are typically taken for mood disorders as the drug is thought to interfere with the chemical serotonin—the brain’s ‘happiness hormone’.

Figures show an estimated 8.7million people in England take antidepressants, about one in seven people, with numbers increasing annually. 

In the US an estimated one in eight people are currently taking an antidepressant, according to the Centers for Disease Control. 

Psychiatrists advise patients concerned about the side effects of antidepressants to talk to their medical professional about their options.

Clinicians can sometimes offer an alternative dose, a different drug, or prescribe another medication to combat the side effects.

They urge patients who are taking them not to quit without talking to the medical professional responsible for their care first to ensure they are adequately supported.