Electroconvulsive therapy produces a brief seizure under anesthesia and remains one of the fastest-acting treatments for severe depression, particularly when other medications have not worked

Electroconvulsive therapy (ECT) is a medical procedure in which a patient under general anesthesia receives electrical stimulation to the brain, triggering a controlled seizure lasting 20 to 60 seconds. Despite its dramatic appearance in older films, modern ECT is performed in a hospital or outpatient surgical setting with muscle relaxants, anesthesia, and continuous monitoring. The procedure is most commonly used for severe depression that has not responded to antidepressant medications, depression with psychotic features, or bipolar depression when rapid response is critical.

The evidence for ECT's effectiveness in severe depression is stronger than for most other psychiatric treatments. A 2017 meta-analysis in JAMA Psychiatry found remission rates of 50 to 60 percent in people with treatment-resistant depression—meaning depression that persisted despite adequate trials of at least two different antidepressants. For comparison, adding a second medication or switching medications in treatment-resistant cases produces remission in roughly 10 to 20 percent of people. ECT also works faster: improvement often appears within days to weeks, whereas antidepressants typically require 4 to 6 weeks.

Key Takeaways

  • ECT produces remission of severe depression in 50 to 60 percent of people with treatment-resistant cases, faster than medication adjustments.
  • The procedure carries real risks, including memory loss (usually temporary but sometimes lasting), confusion, and rare cardiovascular complications.
  • ECT is most often used for severe depression unresponsive to medications, depression with psychotic features, and bipolar depression when rapid response matters.
  • Maintenance ECT—ongoing treatments after initial response—can prevent relapse but requires repeated anesthesia and monitoring.
  • The mechanism remains incompletely understood; researchers believe it involves changes to brain networks and neurotransmitter systems, not straightforward the seizure itself.

How ECT affects the brain and why it works

The exact mechanism of ECT remains unclear, which is unusual for a treatment this widely used. The seizure itself is not the active ingredient—seizures from other causes do not treat depression. Instead, researchers believe ECT works by altering communication between brain regions and changing levels of neurotransmitters like serotonin and norepinephrine.

Imaging studies show that ECT increases activity in the prefrontal cortex and reduces overactivity in the amygdala (the brain's alarm center), patterns associated with mood improvement. Animal studies suggest ECT may also promote neuroplasticity—the brain's ability to form new connections—and increase levels of brain-derived neurotrophic factor (BDNF), a protein involved in nerve cell growth. Human studies have not yet confirmed whether BDNF changes directly cause the antidepressant effect, but the correlation is consistent enough that researchers continue investigating it.

One reason ECT works when medications fail is that it does not depend on the same neurotransmitter systems. A person whose depression does not respond to serotonin-boosting drugs may still respond to ECT, suggesting the two treatments engage different biological pathways.

Memory loss and cognitive side effects

Memory problems are the most common and most concerning side effect of ECT. Most people experience some degree of retrograde amnesia—loss of memories from before treatment—and anterograde amnesia—difficulty forming new memories during the treatment course. For many, these effects are temporary and resolve within weeks to months after treatment ends.

However, some people report persistent memory loss, particularly for events in the months or years before ECT. A 2019 study in The Journal of ECT found that roughly 30 percent of people reported subjective memory problems lasting beyond six months. Whether this represents true persistent memory loss or a change in how memory feels is debated; objective testing (like standardized memory tests) often shows recovery, but patients' own experience may differ from test results.

Other cognitive effects include confusion, difficulty concentrating, and slower processing speed, typically most pronounced when ready after each treatment and improving over days. Older adults and people with pre-existing cognitive impairment may experience more pronounced or longer-lasting cognitive effects, which is why ECT is used cautiously in these groups.

Physical risks and medical considerations

ECT requires general anesthesia, which carries its own small risks: aspiration, allergic reaction, and rare anesthetic complications. The electrical stimulation itself can cause temporary heart rhythm changes, elevated blood pressure, and increased heart rate during and when ready after the procedure. For people with heart disease, uncontrolled high blood pressure, or recent heart attack, these cardiovascular effects require careful medical evaluation before proceeding.

Muscle soreness, headache, and nausea are common in the hours after treatment and usually resolve quickly. Serious complications—cardiac arrest, prolonged seizure, or stroke—are rare, occurring in fewer than 1 in 1,000 treatments in modern settings with proper monitoring.

Pregnancy is not an absolute contraindication to ECT; some pregnant people with severe depression or bipolar disorder have received ECT when the risks of untreated illness outweighed procedural risks. However, ECT during pregnancy is uncommon and requires consultation with both psychiatry and obstetrics.

Conditions beyond depression where ECT is used

While severe depression is the primary indication, ECT is also used for bipolar disorder (particularly bipolar depression and mixed episodes), catatonia (a state of reduced responsiveness and abnormal motor behavior), and psychotic disorders when medications have not worked. The evidence is strongest for bipolar depression; remission rates are similar to those in unipolar depression.

For catatonia, ECT can produce rapid response—sometimes within one or two treatments—making it a first-line consideration rather than a last resort. Psychotic disorders respond less consistently than mood disorders, and ECT is typically reserved for cases with prominent mood symptoms or when antipsychotics have failed.

Some clinicians have explored ECT for treatment-resistant anxiety, obsessive-compulsive disorder, and other conditions, but evidence remains limited and these uses are not standard practice.

Maintenance ECT and preventing relapse

After a course of acute ECT (typically 6 to 12 treatments over 2 to 4 weeks), some people enter a maintenance phase: ongoing treatments spaced weeks or months apart to prevent relapse. Maintenance ECT can reduce the risk of depression returning, but it requires continued anesthesia and monitoring indefinitely.

Research on maintenance ECT is limited compared to acute treatment. A 2016 review found that maintenance ECT reduced relapse risk compared to no treatment, but the studies were small and did not compare maintenance ECT directly to long-term medication. For most people, the goal after acute ECT is to transition to antidepressant medications or other maintenance treatments, reserving ongoing ECT for those who relapse repeatedly despite medications.

What the research does and does not show

The evidence supporting ECT for treatment-resistant depression is robust, based on multiple randomized controlled trials and meta-analyses. However, most studies are relatively small, and many were conducted decades ago when ECT techniques and anesthesia were less refined than today. Newer, larger trials are limited.

The research does not show that ECT is better than antidepressants for mild to moderate depression—it is not, and medications are tried first for good reason. The research also does not clarify which people will respond to ECT and which will not; response cannot be predicted reliably from demographics, depression severity, or other baseline characteristics. Some people with mild depression respond dramatically, while others with severe depression do not respond at all.

Long-term outcomes beyond one year are poorly studied. Most trials follow people for weeks to months; whether ECT's benefits persist, whether relapse rates differ from medication-treated groups over years, and whether repeated ECT courses carry cumulative cognitive risks remain open questions.

Frequently Asked Questions

Is ECT still used today, or is it outdated?

ECT is still used regularly in psychiatric hospitals and outpatient settings, particularly for severe depression unresponsive to medications. It is not outdated, but it is reserved for specific situations where the speed and strength of response matter more than the side effect profile. Thousands of people receive ECT annually in the United States.

Will ECT change my personality or make me a different person?

ECT does not change personality. It reduces depression symptoms, which can change how you feel and behave, but not who you are. Some people report feeling like themselves again after severe depression lifts. Memory loss can feel disorienting, but it does not alter core personality traits or identity.

Can ECT be used instead of medication for ongoing treatment?

For most people, no. After acute ECT, the goal is to transition to antidepressant medications or other maintenance treatments. Maintenance ECT—ongoing treatments spaced weeks apart—is an option for people who relapse repeatedly despite medications, but it is not standard first-line maintenance and requires repeated anesthesia.

How long does memory loss from ECT last?

For most people, memory problems improve within weeks to months after treatment ends. However, some people report persistent difficulty remembering events from before or during treatment. The degree and duration vary widely and cannot be predicted beforehand. Discussing this risk with your psychiatrist before treatment is important.

What happens if ECT does not work?

If ECT does not produce improvement after a full course of 8 to 12 treatments, other options include trying different medication combinations, psychotherapy, transcranial magnetic stimulation (a non-invasive brain stimulation technique), or other approaches. Lack of response to ECT does not mean depression is untreatable, only that this particular treatment was not effective for you.