Scientists Warn Antidepressant Withdrawal Minimized by Industry-Funded Research

The Hidden Risks of Antidepressant Withdrawal

There is growing concern that a recent review on antidepressant withdrawal effects may not fully capture the risks faced by long-term users. This review, authored by academics with potential ties to pharmaceutical companies, relies heavily on short-term studies funded by the industry. Critics argue that this approach could lead to an underestimation of the severe and prolonged withdrawal symptoms experienced by many individuals.

Understanding Antidepressant Withdrawal

Stopping antidepressants, especially after long-term use, can result in significant and sometimes debilitating withdrawal symptoms. These effects have now been recognized as a public health issue by the UK government. However, it took decades for this issue to gain attention following the introduction of modern antidepressants.

Medical guidelines, such as those from the National Institute for Health and Care Excellence (NICE), previously described withdrawal effects as "brief and mild." This perception was based on studies where participants had only taken the medication for eight to 12 weeks. As a result, when patients later experienced severe, long-lasting symptoms, many doctors dismissed their concerns, believing these experiences did not align with established guidelines.

Research Reveals a Clear Link

Our recent research sheds light on the mismatch between the current understanding of withdrawal effects and the real-world experiences of patients. We found a clear connection between the duration of antidepressant use and the likelihood and severity of withdrawal symptoms.

In a survey of NHS patients, we discovered that those who had used antidepressants for more than two years were ten times more likely to experience withdrawal effects compared to those who had taken the drugs for six months or less. Additionally, they were five times more likely to face severe symptoms and 18 times more likely to experience long-lasting effects.

For individuals who used antidepressants for less than six months, withdrawal symptoms were typically mild and brief. Three-quarters reported no or mild symptoms, most of which lasted less than four weeks. Only one in four of these patients struggled to stop when they wanted to.

However, for long-term users (more than two years), two-thirds reported moderate or severe withdrawal effects, with one-quarter experiencing severe symptoms. Almost one-third of these patients reported symptoms lasting over three months. Four-fifths of long-term users found it difficult to stop their medication despite their efforts.

The Scale of Long-Term Use

According to a BBC investigation, about 2 million people in England have been taking antidepressants for over five years. In the United States, at least 25 million people have used these medications for more than five years. The experiences of people in eight-to-12-week studies are vastly different from those of millions who face prolonged withdrawal symptoms.

Studying what happens after just a few weeks of antidepressant use is akin to testing car safety by crashing a vehicle at low speed while ignoring real-world driving conditions.

A Recent Review and Its Limitations

A new review published in JAMA Psychiatry has raised further concerns. Several senior authors of the review have disclosed financial ties to drug companies. The review draws on short-term trials, similar to those that shaped early treatment guidelines, and concludes that antidepressants do not cause significant withdrawal effects.

The main analysis of the review is based on eleven trials comparing withdrawal symptoms in people who stopped antidepressants with those who continued them or took a placebo. Six of these trials involved participants on antidepressants for eight weeks, four for 12 weeks, and one for 26 weeks.

The review found a slightly higher number of withdrawal symptoms in people who stopped antidepressants but deemed them not clinically significant. It also suggested that these symptoms might be due to the “nocebo effect,” where negative expectations lead to worsened symptoms.

Underestimating the Risk

In our view, the results of the review likely underestimate the risk of withdrawal for the millions of people using these drugs for extended periods. The review found no relationship between the duration of antidepressant use and withdrawal symptoms, but there were too few long-term studies to properly test this association.

The review may also underestimate short-term withdrawal effects by assuming that symptoms experienced when stopping a placebo or continuing an antidepressant cancel out the effects of the drug itself. This assumption is not valid.

We know that antidepressant withdrawal effects overlap with side effects and everyday symptoms, but this does not mean they are the same. People stopping a placebo report symptoms like dizziness and headaches, which are common occurrences. However, symptoms from discontinuing antidepressants tend to be more intense and can require emergency care.

Missing Important Studies

The review also omits several well-designed drug company studies that found high rates of withdrawal symptoms. For example, an American study found that more than 60% of people who stopped antidepressants after eleven months experienced withdrawal symptoms.

The authors suggest that depression after stopping antidepressants is likely a return of the original condition rather than withdrawal symptoms. They base this conclusion on limited and unreliable data from just five studies, relying on participants to self-report events without systematic assessment.

Moving Forward

We hope that uncritical reporting of this review does not hinder the growing recognition of the problem and slow efforts by the health system to support millions of people potentially affected by severe withdrawal symptoms.

Some withdrawal effects are severe enough to require emergency care. It is crucial that future research and guidelines consider the long-term impacts of antidepressant use and provide appropriate support for those discontinuing these medications.