Electroconvulsive therapy, or ECT, is a medical procedure in which a small electrical current is used to trigger a controlled seizure in the brain. It is primarily used to treat severe depression, though it may also be used to treat some other mental health conditions, including bipolar disorder, schizophrenia, and catatonia, among others. In general, ECT is used to treat people with these conditions who have not improved with other treatments or who are in need of a rapid response.

ECT was first used in the late 1930s after it was discovered that the symptoms of people with severe mental illness improved after having a spontaneous seizure. At first, doctors used chemicals to induce these seizures as a treatment. Then, in 1938, Ugo Cerletti, an Italian neurologist, and Lucio Bini, an Italian psychiatrist, first used electrical currents to trigger seizures in a patient with (likely) catatonia who had been admitted to hospital. After 11 treatments, the patient’s symptoms improved enough that he was discharged.

While early ECT was performed without anesthesia and was associated with side effects, including severe memory loss as well as bone and tooth fractures (caused by convulsions), it proved an effective treatment, and it began to be used across Europe and in the United States to treat schizophrenia, as well as severe depression and other mental health conditions.

In the years since it was first used, ECT techniques have evolved significantly, making the procedure safer and more effective. ECT is now performed using general anesthesia, muscle relaxants, and smaller doses of electrical current that are delivered via carefully positioned electrodes, reducing side effects and improving patient outcomes.

Today, ECT is considered a safe, effective treatment that can be used to treat children, adolescents, and adults.

In ECT, a doctor, typically a psychiatrist, uses a device to deliver a carefully controlled electrical current to a patient’s brain via two electrodes placed on the scalp. The electric current induces a generalized seizure, which is a seizure that affects both the left and right hemispheres of the brain at the same time.

While it is unknown exactly how ECT improves symptoms in people with depression and other mental health conditions, studies have shown that it results in chemical changes in the brain that may alter communication between cells in the brain.

Symptoms typically begin to improve rapidly with ECT, often after only a few treatments. However, a full course of ECT usually involves six to 12 treatments given every two to three days. Some people may need fewer or more treatments, or more frequent treatments.

A successful course of ECT can significantly reduce symptoms—and even lead to a resolution of symptoms. People whose symptoms have resolved after a course of ECT treatment are said to be in remission. To prevent symptoms from returning, they may receive “continuation ECT,” in which they continue to receive a single ECT treatment following a schedule that gradually increases the interval between treatments for approximately six months. The interval between treatments is individually tailored, with treatments given at a frequency that maintains improvement. Some people may still require additional ECT treatments to prevent symptoms from recurring after continuation ECT. This type of ECT, known as “maintenance ECT.”

ECT may be administered as an inpatient or outpatient procedure depending on the severity of the patient’s mental health condition, and may be used in combination with other treatments.

ECT may be used to treat a number of mental health conditions, including:

• Depression (major depressive disorder), in particular:
  • Depression that has not improved with medications
  • Severe depression
  • Depression with psychotic symptoms (such as delusions and hallucinations)

People with depression who cannot tolerate medications may also be treated with ECT.

• Bipolar disorder, including treatment of manic phase, depressive phase, or mixed phase bipolar disorder.
• Catatonia, in particular:
  • When medications (i.e., benzodiazepines) are ineffective
  • For life-threatening symptoms, such as autonomic instability (when the autonomic nervous system, which controls involuntary functions such as heart rate, blood pressure, and breathing rate, does not work properly), from malignant catatonia, a life-threatening condition
  • For people with major depressive disorder or bipolar disorder with catatonia
• Schizophrenia, in particular:
  • In combination with antipsychotic medications, or
  • When antipsychotic medications are ineffective
• Schizoaffective disorder, in particular:
  • Intense mood symptoms such as depressive or manic symptoms
  • When there is inadequate symptom improvement with medications

ECT is safe to use in pregnant people, elderly patients, and people with cardiac pacemakers or implantable cardioverter defibrillators (ICDs).

Before receiving ECT, patients undergo a medical evaluation to identify medical conditions or treatments that could increase the risk of side effects from ECT or reduce its effectiveness. The pre-treatment evaluation typically involves:

• A psychiatric and mental status exam, including a review of the individual’s history with ECT, other treatments previously used to treat the current mental health condition, and family history of mental health conditions
• A physical exam and a review of the individual’s medical history
• Blood tests, which may include a complete blood count, kidney function, liver function, and blood chemistry tests, among others
• A computed tomography (CT) or magnetic resonance imaging (MRI) scan of the brain if there is suspicion of a tumor or other abnormalities, or increased intracranial pressure.
• Other tests may be ordered depending on individual characteristics.

The pre-treatment medical evaluation also allows doctors to establish the individual’s mental health and cognitive status. This pre-treatment status can serve as a reference point to determine how well ECT treatment is working.

People with certain medical conditions are at increased risk of complications during ECT. These conditions include:

• Brain tumor or another abnormality that occupies space in the brain (collectively known as space-occupying cerebral lesions)
• Increased intracranial pressure
• Recent heart attack
• Recent stroke
• Brain aneurysm
• Aortic aneurysm
• Retinal detachment
• Pheochromocytoma

Often, doctors can take precautions to lessen the risk of complications during ECT. For example, they may adjust medications, ensure that certain conditions are treated and resolved prior to ECT, and closely monitor patients at increased risk for complications during ECT.

ECT causes a temporary increase in blood pressure, pulse, and intracranial pressure, which may worsen certain cardiovascular, lung, and central nervous system (CNS, the brain and spinal cord) conditions during treatment. ECT also causes the heart to work harder than usual. People with cardiovascular, lung, or CNS conditions may need to see a specialist for evaluation and, in some cases, treatment, prior to receiving ECT. In some cases, a medical condition that may worsen during ECT will need to be treated before starting ECT. Medications may also be used during ECT to lessen increases in heart rate and blood pressure to improve patient safety.

The ECT procedure is performed by a medical team that usually includes a psychiatrist, an anesthesiologist, and a nurse.

ECT requires several steps:

Scalp electrode placement:

Before the procedure begins, while you are awake, the medical team will place electrodes on your scalp, ensuring that they are positioned correctly. There are three common electrode positions:

• Bilateral (or bitemporal), in which an electrode is placed on each temple. This method is highly effective in treating depression and may provide faster symptom relief than the other electrode placements, though it has also been associated with more cognitive side effects than unilateral electrode placement.
• Unilateral, in which one electrode is placed on the temple (usually on the right side) and one electrode just to the right of the highest point on top of the head (vertex). Studies have shown that unilateral positioning is as effective, though not as fast-acting, as bilateral electrode positioning, with fewer cognitive side effects.
• Bifrontal, in which an electrode is placed on the forehead above the outer corner of each eye. The effectiveness and side effects of this method are similar to that of bilateral electrode positioning.

ECT procedure:

You will then be given a short-acting anesthetic (such as methohexital or propofol) through an IV to put you to sleep for around 5 to 10 minutes, so you do not feel any pain during the procedure.

You will also be given an injection of a muscle relaxant called succinylcholine. This drug reduces muscle contractions during the seizure that can damage the bones and ligaments. A blood pressure cuff may be placed around your ankle and inflated to prevent the muscle relaxant from reaching the foot, which allows the foot to move during the seizure. The foot movement helps the medical team confirm and measure the duration of muscle contractions. However, because the muscle relaxant does not stop muscles involved in chewing and clenching the jaw from contracting, a bite block will be inserted into the mouth to protect the tongue and teeth from injury.

After the anesthetic and muscle relaxant have been administered, the psychiatrist will deliver a brief electric pulse to your brain via the electrodes on your scalp. The electrical current causes a generalized seizure that usually lasts between 20 and 60 seconds. Because of the anesthesia and muscle relaxant, the body does not convulse during ECT treatment, though the arms, legs, or other parts of the body may move a little.

Throughout the procedure, the medical team closely monitors brain, muscle, and heart activity, as well as blood pressure and blood oxygen levels. Additional electrodes may also be placed on your scalp, chest, and foot to monitor electrical activity in your brain, heart, and muscles, respectively, during ECT treatment.

After an ECT procedure, you may have a headache, muscle aches, and feel nauseous. These are common, temporary side effects (see below for more information about side effects) that are usually worse with the first treatment and are greatly reduced for subsequent treatments. They can be treated with medications such as acetaminophen or ibuprofen.

People may also feel confused due to the seizure and anesthesia. Confusion usually gets better within an hour after the treatment. Temporary memory loss is also common. It usually gradually resolves over the course of weeks or months.

Due to the possibility of developing memory problems, health care providers may recommend that people refrain from making important decisions until a week or two after completing a course of ECT treatment.

ECT is safe, though, as with any medical procedure, it can have side effects. Most side effects are minor and temporary.

Common side effects include:

• Headache
• Jaw soreness
• Fatigue
• Muscle pain (caused by the muscle relaxant used during ECT)
• Nausea and vomiting (caused by the anesthesia)

These side effects are typically short-lived and resolve on their own, without treatment. However, pain relievers or other medications may help alleviate symptoms.

Cognitive side effects can also occur, including:

• Confusion, which usually lasts for a few minutes to an hour after the procedure, though in older adults, it may last for hours or even days
• Memory loss, the severity of which varies among patients. During a course of ECT, people may have trouble recalling new information. This type of memory problem (known as anterograde amnesia) usually resolves within two to four weeks after treatment ends. People may also have difficulty recalling events during treatment and several weeks or months prior to ECT (known as retrograde amnesia). This type of memory loss develops over multiple treatments and is slower to resolve than anterograde amnesia, typically taking weeks or months to resolve once treatment is completed. People who have this type of memory loss may not recover some memories of events prior to ECT treatment.

Rare side effects may include:

• Heart arrhythmia
• Myocardial ischemia (reduced blood flow to the heart) or heart attack
• Prolonged seizure (when the patient’s seizure lasts 2 to 3 minutes or longer)
• Spontaneous seizures (known as tardive seizures, these may occur during the recovery period after treatment)
• Aspiration pneumonia (a lung infection that occurs when stomach contents, food, or other foreign materials are inhaled into the lungs, which may occur if the patient’s stomach is not empty during the procedure)
• Bone fracture (for example, in people with severe osteoporosis, which increases the risk of fractures)
• Injuries of the tongue and/or teeth

ECT is an effective, fast-acting, and safe treatment for a number of mental health conditions. The outlook for people treated with ECT can vary based on several factors, including the severity of symptoms, the individual’s overall health, and the mental health condition being treated:

• Depression: Randomized trials involving people with severe depression have found that ECT outperforms other treatments, including standard antidepressant medications and cognitive behavioral therapy (CBT). Remission (resolution of symptoms) occurs in 70% to 90% of patients who receive ECT, compared to around 30% for antidepressants.
• Bipolar disorder: Studies have found ECT to be an effective treatment for people with bipolar disorder with mood episodes, including those for whom medications have been ineffective. For example, a study that included people with bipolar disorder for whom medication alone was ineffective found that ECT in combination with medications improved symptoms in 69% of cases.
• Catatonia: Studies have shown that ECT improves symptoms in 53% to 93% of people with catatonia, including those for whom medications have been ineffective.
• Schizophrenia: Studies have found ECT to be an effective treatment for people with schizophrenia for whom medications have been ineffective. ECT is estimated to result in remission in 40% to 80% of patients.
• Szhizoaffective disorder: A study found that ECT resulted in symptom improvement in all patients with schizoaffective disorder that had not improved with other treatments. Six months and one year later, 77% of these people continued to have improved symptoms.

After completion of a successful course of ECT, symptoms may return. Additional ECT treatments, administered with increasingly longer intervals between them, often in combination with medications and/or talk therapy, may be used to help prevent symptom recurrence.

“ECT at Yale is performed by physicians with international reputations for excellence,” says Yale psychiatrist Robert Ostroff, MD. “As a group, the doctors performing ECT have extensive experience with selecting patients who will benefit from the treatment and also with performing the treatment. Patients come from around the United States and abroad to benefit from our expertise. We pride ourselves as being the gold standard for this treatment.”