Department of Psychiatry
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Electroconvulsive therapy (ECT)

Electroconvulsive therapy (ECT) is an effective treatment for major depression, bipolar disorder, schizophrenia and other mental health conditions. Learn more about this treatment option and how it's done, below.

Why does ECT have such a negative reputation?

Part of it may be what’s been portrayed in movies and the media. Many people see ECT as shock therapy where there is a surge of electricity that is painful and scary, almost like a punishment for having a mental health condition. And some of it may be fear of the unknown. But the truth is, ECT is actually one of the most effective treatments for major depression and some other mental health conditions.

Is ECT a first-line treatment?

No, it’s usually recommended after other treatments have been tried unsuccessfully, including medications and talk therapy. But for some patients who have severe disease, can’t take their medications or may be suicidal, ECT could be a more immediate option.

Can you explain how ECT is done, step by step?

Before any patient is scheduled for ECT, they will meet with their medical team to make sure it’s an appropriate treatment and safe for them. They will also need to see an anesthesiologist before the treatment to review any medical conditions and medications they might be taking.

On treatment day, patients are brought into a procedure room lying down on a stretcher. It’s not a full surgical suite, but more like a large clinic room. The interprofessional team consists of psychiatric and post-anesthesia care unit (PACU) nurses, an anesthesiologist and a psychiatrist. The team will go over the patient’s medical history and previous treatments and will then insert an intravenous (IV) line. The medications are given by the anesthesiologist through this IV line.

The psychiatrist will then do a quick set up test to measure the right resistance. The patient will feel two cylindrical paddles held up to each temple with some gel, and will only feel the cold wet gel during this testing step.

When everything is ready, the patient is given oxygen through a face mask. The anesthesiologist then gives medication through the IV line to let the patient go to sleep and to keep their muscles relaxed. The patient is then fitted with a mouth guard to protect their teeth. When the electrical stimulus is administered, it induces a controlled seizure that lasts between about 15 seconds to one minute. The patient doesn’t feel anything and is sleeping comfortably. Within a few minutes, the patient beings to wake up and is taken by stretcher to another room to recover.

In the recovery area, the patient wakes up more completely, and there are nurses there to monitor them and assist. After a few more minutes, the patient will be more awake and alert. Once their blood pressure, heart rate and breathing are all stable, they can get ready to go home. The patient will go home accompanied by a responsible adult, with details arranged before the treatment takes place. Often, they are awake and ready to go home within two hours of having the treatment.

How many treatments are needed?

Multiple treatments are usually required, and the average is about 12, but the total amount will depend on each patient.

How effective is ECT?

Very! It’s between 70 to 80 per cent effective in improving symptoms in major depression. In about 60 per cent of patients, ECT will lead to a full remission. It’s difficult to say with certainty if symptoms will return, but if they do, ECT can be done again.

Are there any side effects?

As with any medical treatment, there are risks for side effects. The most common with ECT include muscle pain and headache. Some patients may experience memory problems, nausea or high blood pressure, but these side effects are typically temporary. Medications can often be adjusted and the treatment tailored to each patient to help them be as comfortable as possible. All in all, it’s a very safe procedure and we are right there to monitor the patient closely.

People may worry that ECT will change who they are

That’s a big fear that patients may express, but that is not what ECT does. When it comes to memory loss, some patients may not remember having the procedure done, or perhaps details of the treatment day. But ECT’s effect on memory is typically short-lived and does not involve forgetting loved ones or major events that happened in the past. In fact, many people who have trouble thinking as a result of their severe depression often notice considerable improvement in memory and cognitive function once their depression is successfully treated.

Knowing the majority of people still see ECT as harmful and something to be feared, what can be done?

Sunnybrook doctors are currently involved in research surrounding virtual reality and ECT, in order to help patients know what to expect if they are having ECT. This virtual reality tour will allow patients to first experience all these steps of the treatment in a safe space. We hope this will help educate patients and reduce their anxiety. ECT is an important and effective treatment, and we want patients to know there is a whole team involved in making sure they are safe and comfortable.

"The Story of ECT" comic strip

A comic strip outlining the history, and an overview, of ECT

Source: Zhu, A, Phuong, M and Giacobbe, P. 2018. The Story of ECT: Behind the Scenes of a Controversial yet Effective Treatment. The Comics Grid: Journal of Comics Scholarship, 8(1): 13, pp. 1–10, DOI:

» View plain-text of the above graphic

The story of ECT

Behind the Scenes of a controversial yet effective treatment

“It is hard in fact to think of anywhere where the mismatch between rhetoric and reality is as great as it has been in the history of ECT.”

-Shorter & Healy , 2007

Electroconvulsive therapy (ECT) has been a hot topic in the field of psychiatry.

One Flew Over the Cuckoo’s Nest (1975)

ECT depictions in media often illustrate a frightening, inappropriately applied procedure…with dubious benefits.

(Shorter & Healy, 2007)

In the early days of ECT, there were many horror stories of its abuse. In 1942, when ECT arrived at Milledgeville State Hospital, ECT became synonymous with “punishment” to patients (Shorter & Healy, 2007). Although measures were taken to protect patient safety later on, these were rarely included in the dramatic depictions of ECT at the cinema.

These negative media depictions have been pervasive. Since the 1948 film The Snake Pit, subsequent forms of media have perpetuated the idea that ECT is a dangerous treatment performed on unwilling patients despite current evidence stating the contrary (Sienaert, 2016).

The influence of these negative images is also strong, where it has been shown that upon viewing films that negatively depict ECT, medical students would not support the procedure’s use (Walter et al., 2002).

Consequently, the lack of accurate information and initial misuse of ECT in its very early days of implementation sparked a resistance movement as part of the anti-psychiatry movement in the 1960s-1970s (Payne 2009). In conjunction with negative and inaccurate portrayals of ECT in the media, this has led to apprehension from the general public regarding this procedure.

But what does ECT really look like? And more importantly, what does ECT look like today?

Real-life application of ECT is vastly different than the media portrayals. Performed by trained healthcare professionals, electrodes are attached to the patient’s head, which send small controlled electrical currents to stimulate the brain.

In doing do, while the patient is under general anesthetic, the process induces a “mini-seizure” that has been shown to be effective against psychiatric disorders. However, the precise mechanisms remain unclear (Singh and Kar, 2017).

To further elucidate the mechanisms of action, there are a multitude of potential neurobiological pathways to explore. There have been observed differences in brain structure and activity pre- and post-ECT in different areas of the brain; suggesting that these changes might explain observed improvements in symptoms (Takamiya et al., 2018).

Through a review of the current literature surrounding ECT, the mechanism, safety, efficacy, and side effects of ECT will be discussed.


In psychiatry, a biopsychosocial model is often considered, where many factors which may cause psychiatric disorders are involved; including biological and environmental elements. Likewise, while effective treatments for psychiatric disorders have been recognized, why and how they work remain outside our scope of knowledge.

Even so, while there isn’t one clear mechanism that explains the therapeutic benefits of ECT, studies have explored potential neurobiological mechanisms of actions.

Some hypotheses for these benefits including enhancing neuroplasticity, levels of neurotransmitters, and immune mechanisms. For example, in the brain, the amygdala is a site responsible for regulating emotion, while the hippocampus is involved in memory (Bouckaert et al., 2016).

One proposed mechanism of how ECT improves symptoms is that it may result in an increase in grey matter volumes in these brain regions (Bouckaert et al., 2016). As well, ECT has been implicated in increasing hippocampal functional connectivity in the brain (Singh and Kar, 2017).

Increased connectivity within the brain has also been seen after ECT treatment. With ECT, there are increases in neurotransmitters which are associated with forming networks involved in the regulation of attention and mood (Abbott et al., 2014).

These networks within the brain are often affected in individuals with depression; and thus ECT may play a role in upregulating and improving functional connectivity in the brain.

For example, glutamate is an excitatory neurotransmitter that is found to be dysregulated in various psychiatric disorders, and it has been suggested that ECT could rectify these imbalances among patients (Pfleiderer et al., 2003).

Even so, with all these potential mechanisms of action in mind, the literature on ECT is still expanding in this area to understand the how and the why.


ECT is performed by a team of trained healthcare professionals, including psychiatrists, nurses, and anesthesiologists. These members of the healthcare team are all involved in providing the safe application of the procedure.

In the past, patient injuries (ie. factures, injuries to teeth, and muscle damage) after ECT were common, often resembling injuries seen as a result of seizures (Healy and Shorter, 2007). Today, due to the use of proper anesthetic techniques, ECT is much safer and well-tolerated. For instance, muscle relaxants are provided to the patient prior to the procedure to prevent self-injury as a result of the induced “mini-seizure”.

Furthermore, nowadays, patients are always discharged within the same day as the ECT procedure.

During the application of the procedure, a small current is used to stimulate the brain for a few seconds. At most, a small twitch of the feet is usually the only observable feature of the entire procedure.

The patient is consistently monitored throughout the entire procedure. Oxygen is provided to the patient and vital signs, such as the patient’s heart rate and blood pressure, are consistently evaluated.

The mortality rate is believed to be less than 1 out of 98,000 treatments, which is comparable to the mortality rate of general anesthesia (Watts et al., 2011). As well, complications typically arise in 1 in 200 patients, and these complications can be defined as occurrences of a transient rise in blood pressure or heart rates outside the range of normal for a brief period of time (Nuttall et al., 2004).

Furthermore, something that is not often addressed in the media, but is an important topic of consideration in any healthcare intervention, is the idea of patient consent.

Often in the media, patients are seen to resist ECT, implying that patients do not have a say as to whether they undergo the procedure. These scenes diminish the importance of consent in making any healthcare decisions, ECT or otherwise (Sienaert, 2016).

In reality, healthcare professionals follow specific guidelines to obtain patient consent prior to the initiation of ECT (Enns, Reiss and Chan, 2010). If a patient has been appropriately evaluated to be incapable of making their own decisions regarding their own health, a substitute decision maker (SDM) may choose for the patient to undergo ECT.

Providing informed consent includes ensuring that the patient or SDM understands the risks and benefits of ECT and alternative treatment(s) as well as has time to ask questions about their condition and management. Providing informed consent is an ongoing process that occurs throughout the sessions and may be withdrawn at any time. Furthermore, the patient can choose to forego ECT even as they walk into the treatment room (Enns, Reiss and Chan, 2010).


ECT is not used to treat every condition. In fact, it is indicated and has shown to be very effective in certain clinical situations. The procedure is indicated for treatment-resistant depression and major depressive disorder with features such as psychosis, catatonia, inanition, and suicidal ideation (Fink, 2009).

An objective measure known as the Hamilton Depression Rating Scale is often used to assess improvements in patients’ baseline for depression. This scale includes questions about patient’s symptoms such as depressed mood, insomnia, and anxiety. A systemic review found that patients who have undergone ECT see more significant improvement in these symptoms than those in placebo or medication groups (UK ECT Review Group, 2003).

An important question to consider is if ECT, at a minimum, is comparable to current medications. A meta-analysis examining the efficacy of ECT to treat depression found that a positive response was seen almost 4 times greater with the use of ECT in comparison to antidepressant medication (Pagnin et al, 2008).

The patient response rate to ECT is also fast, demonstrating the procedure’s usefulness for severe depression or with active suicidal ideation. One study found that about half of the patients responded to the treatment after 3 sessions and 87% of patients achieved remission after a full course of ECT in 8 sessions (Husain et al., 2004).

In contrast, the general clinical practice when prescribing pharmacotherapy is to wait every two weeks to evaluate any changes experiences by the patient, potentially leading to extended courses of treatment for patient that could have medication-resistant depression (Blier, 2009).

One of the concerns surrounding ECT is that the effects wear off over time. However, after the initial course of treatment, ongoing maintenance may often still be needed to maintain remission. Thus, maintenance ECT can be an option to pursue (Kellner et al., 2006). As well, depending on the level of remission and patient preferences, medications and psychotherapies such as cognitive behavioural therapy are also offered.

Side Effects

Common side effects after ECT can include headache, muscle stiffness, nausea, and confusion. These symptoms are often caused by the anesthetic or muscle relaxants provided during the treatment. However, these side effects are temporary and do not last long for the majority of patients (CAMH: ECT, 2018).

However, one of the major fears surrounding ECT is that the treatment may lead to memory loss. In fact, media depictions of ECT often show the therapy being used to intentionally cause memory loss in patients (Sienaert, 2016).

It’s important to note that memory loss experienced after ECT is variable among patients, especially in published literature. In one study, it was found that a minority (26%) of patients would report experiencing subjective memory worsening (Brus et al., 2017). Patient-reported memory loss may last for a few weeks during the duration of ECT, but typically resolves with time (Maric et al., 2016).

That said, there are anecdotal patient reports of experiencing long-term memory loss and cognitive changes that should be kept in mind (Andre 2009).

Therefore, it is often suggested that during the course of ECT, any major decisions that the patient needs to make are postponed, and arrangements are made for someone to help the patient to and from the ECT facility due to the initial experienced confusion (CAMH: ECT, 2018).

As of now, further research is being completed on the extent of memory loss, which patient populations may be susceptible to it, and methods to reduce its occurrence. Generally speaking, ECT is a safe procedure, in spite of the general public’s perceptions or depictions in the media. While the idea of one’s memory worsening during the duration of ECT can be concerning, it is important to note that it is typically a self-limiting side effect. In fact, as various psychiatric disorders, such as depression, can impact cognitive function, it is often found that by using ECT as a form of treatment, overall memory and cognition can improve with time (Maric et al., 2016).

Moving into the long-term effects of ECT, one may wonder what is life like for a patient after undergoing ECT. In a meta-analysis investigating patient-reported outcomes after treatment, ECT was found to globally improve patients’ health-related quality of life, which included parameters such as physical functioning, bodily pain, social functioning, and mental health (Giacobbe et al., 2018). Therefore, ECT can play an important role in treating and improving patients’ functioning.

With the advent of new neuromodulation devices which stimulate neural activity through different means, new treatment options are also being explored to determine their efficacy is psychiatric conditions such as depression. For example, rTMS (Repetitive Transcranial Magnetic Stimulation) uses magnetic field pulses to stimulate regions of the brain (Brunelin et al., 2007).

DBS (Deep Brain Stimulation) is currently a procedure that has shown a lot of promise in treating disorders such as Parkinson’s as well as neuropsychiatric conditions. A “brain pacemaker” is inserted into the brain to stimulate a target in the brain (Mayberg et al., 2005).

In general, ECT has undergone unfair scrutiny by the public eye due to its persistent, inaccurate portrayals in the media. Conducted by trained, interprofessional teams, it has great potential in improving patients’ acute symptoms and long-term quality of life.

Although there is still much to learn about its mechanisms of action, these questions inspire further investigations into how ECT is able to transform patients’ lives for the better.