What is ketamine?
Ketamine was discovered in 1956, and approved by the FDA in 1970. It is widely used as an anesthetic, in children, adults, and the elderly, as well as in veterinary medicine. Millions of people have been treated worldwide, with an excellent safety record. As an anesthetic, ketamine is included in the World Health Organization's Model List of Essential Medicines.
The first report of ketamine's effectiveness in psychiatric disorders was published in 2000. Since then, numerous case reports and placebo controlled studies have been published, in many countries. Ketamine is uniquely effective for treatment of depressive disorders, both unipolar and bipolar. It often rapidly reduces suicidal thinking and wishes. It is often effective when other treatments have failed. A smaller number of studies also support its effectiveness in severe anxiety disorders, and some forms of chronic pain.
What are the chances of responding to ketamine treatment?
Some patients with depression respond to the very first treatment with ketamine. Most will respond to a series of 4 – 6 treatments. The degree and duration of response usually increases after a series of treatments. Complete remission of symptoms is usually achieved by about 7 out of 10 patients, based on available research findings.
Unfortunately, not everyone responds to ketamine treatment. Those who have not improved after 6 infusions are unlikely to benefit from further ketamine treatments. Other treatments should then be considered.
How many treatments are needed?
For best, and longest lasting results, an initial series of six ketamine infusions are usually recommended, over about 3 weeks.
How long does improvement last after treatment?
After a successful series of treatments, the effects may continue from several weeks to several months. A few patients experience longer periods of remission. However, a good response to ketamine is not usually permanent. To reduce the risk of relapse, an oral antidepressant medication is usually prescribed. Counseling or psychotherapy is also recommended.
Patients with persistent mild depression, chronic pain, serious health problems, substance abuse, or other severe stressors may be more likely to experience an earlier return of more depression and anxiety symptoms.
How long can a person be treated with ketamine?
There is no specific limit on duration of treatment with ketamine. Appropriate treatment should include ongoing efforts to find effective oral medications or other treatments, in order to minimize the frequency and duration of ketamine therapy.
I live too far away to travel to your clinic. Where else can I receive this treatment?
Ketamine infusion clinics are gradually opening around the country. Some are operated by psychiatrists, and some by anesthesiologists or other physicians. The cost of treatment varies widely. Ketamine treatment is also available at some medical school affiliated psychiatric clinics, often as part of research studies. Many clinics offering ketamine treatment are listed on the web site Ketamine Advocacy Network.
Is ketamine an FDA approved medication?
Ketamine is FDA approved for use in the United States, as an anesthetic during surgical procedures. Ketamine is not approved for treatment of psychiatric conditions. Its use as a psychiatric treatment is therefore considered to be “off label.” “Off label” does not mean that it is experimental, ineffective, or illegal. Many other medications are routinely and legitimately prescribed by physicians for unapproved indications, based on additional scientific research completed after a drug's approval.
What happens if my symptoms return?
If symptoms of depression return following ketamine treatment, the treatment plan is reviewed, and medications may be changed. Some patients will benefit from continued maintenance treatment with ketamine, at a reduced frequency. There is currently no evidence of additional adverse effects occurring with maintenance ketamine treatment. There is no evidence that patients develop tolerance, or loss of ability to respond to ketamine, as a result of repeated treatments.
Can ketamine be used at home?
We do not currently recommend, prescribe or dispense ketamine for home use. Research is underway to identify similarly effective drugs which may be safer for home use.
Why isn't ketamine more widely used for treatment of psychiatric disorders?
Most psychiatrists are now aware that ketamine is a potentially effective treatment for many people with depression, but they do not prescribe or recommend it, for a variety of reasons.
Most psychiatrists are not prepared to offer intravenous infusion therapy in their offices. They remain hopeful that further research will eventually identify similarly acting medications which can be safely prescribed and taken by mouth, at home.
Physicians may be concerned about possible abuse of ketamine. Because ketamine has sometimes been used illegally, it is classified by the DEA as a Schedule III controlled substance. However, medically supervised use of ketamine has never been shown to cause physical dependence or withdrawal. Even prolonged use of ketamine for medical purposes has not led to addiction.
Some psychiatrists argue that treatment with ketamine is premature, because there has been insufficient research to assess possible undiscovered adverse effects with prolonged treatment. In fact, there has been extensive experience with the drug over a half century of use as an anesthetic, as well as more than 17 years of research in psychiatry.
On the other hand, severe depression and anxiety disorders cause much suffering and disability, as well as increased risk for suicide, substance abuse, loss of employment and relationships. Currently approved treatments are often ineffective, or only partly effective, and often have many side effects. Alternatives to the standard treatments are urgently needed.
As for any proposed treatment, the physician and patient must always balance the expected benefits against the risks, costs, and side effects of treatment, and the available alternatives. We believe that the scientific and clinical evidence now supports ketamine as an effective and safe treatment for many patients with severe depression and anxiety disorders, when it is used under appropriate medical supervision. We believe that people with severe depression and anxiety disorders, who have not responded to trials of antidepressant medication and psychotherapy, should have the opportunity to obtain potentially more effective treatments.
Who is most likely to respond to ketamine therapy?
The most common characteristic of people who respond well to ketamine infusion therapy is presence of severe and prolonged symptoms of depression, which are not relieved by other treatments. Ketamine often rapidly reduces suicidal thoughts and wishes, in persons with
severe depression. Ketamine is also frequently effective in persons with severe anxiety disorders. There is no evidence of differences in effectiveness of ketamine based on gender, race, age, or other factors.
Who should not receive ketamine treatment?
Ketamine has not been adequately studied as an initial treatment for depression or anxiety. Other treatments should almost always be tried before ketamine.
Persons who are actively abusing alcohol or other drugs are unlikely to respond to ketamine, and may be at greater risk of adverse effects. These persons should seek appropriate assistance, to achieve a period of abstinence, prior to ketamine treatment.
Ketamine usually results in a mild increase in blood pressure and heart rate, lasting for 1 – 2 hours. For this reason, persons with severe and uncontrolled high blood pressure should not receive ketamine until the blood pressure is under better control. Ketamine should also not be given to persons with conditions which could be worsened by a brief period of elevated blood pressure.
Persons with sleep apnea can be safely treated with low doses of ketamine. However, relief of depression is less likely, unless the sleep apnea is also treated.
Office-based ketamine therapy is not recommended for persons receiving high doses of prescribed narcotic pain medications, due to increased risk of respiratory depression.
Benzodiazepine tranquilizers and sedatives, such as Xanax (alprazolam), Valium (diazepam), Klonopin (clonazepam) and others, may reduce the effectiveness of ketamine therapy. If possible, these medications should be reduced or discontinued prior to ketamine therapy.
High doses of tranquilizers should not be stopped without medical supervision.
Ketamine therapy is not usually recommended during pregnancy, because the possible risks of harm to the fetus are unknown. Breastfeeding should be avoided for 12 hours after a ketamine treatment.
Ketamine is not used for treatment of schizophrenia, because it may worsen the condition.
More about chronic pain and ketamine.
A few studies have described ketamine infusions for treatment of certain chronic pain conditions, including fibromyalgia and complex regional pain syndrome (CRPS), also called reflex sympathetic dystrophy (RSD). Short-term reduction of pain has been achieved by some, but results are mixed.
We have observed patients who experience improvement of chronic pain with low doses of ketamine, when it is used for treatment of depression. While further research is needed, we believe that ketamine infusion therapy is sometimes effective for temporary reduction of
chronic pain, especially when significant depression is also present. Unfortunately, there is no evidence of long term or permanent pain relief, as a result of ketamine treatment. For patients with chronic pain conditions, consultation and continued treatment with the patient's primary care physician or pain management specialist is essential.
How do I prepare for a ketamine treatment?
All patients must be accompanied by a designated driver, or treatment will not be provided. Do not plan to return to work or school, drive, make important decisions, or operate machinery during the rest of the day. An excuse will be provided if necessary.
You may eat or drink lightly, but please do not eat a heavy meal prior to treatment.
Do not use alcohol, narcotics, tranquilizers, or sedatives before a ketamine treatment. Discuss with Dr. Jackson, if you are regularly taking prescribed narcotic pain medications.
Please call to reschedule your treatment if you have a fever, or if you are suffering from influenza or another acute or contagious illness.
If you wish to listen to music or watch a movie during your treatment, please bring your own player and headphones.
Describe a ketamine treatment.
Ketamine is administered in our office. You will be asked to sign a consent, indicating that you are aware of the nature of the treatment and its possible side effects. A small needle is placed in a vein, usually in a forearm. The patient is seated in a comfortable recliner. The medication is given slowly, over about 40 minutes. During the treatment, the patient is monitored by nursing staff, and the physician is also present. If the patient wishes, a family member or friend may be present. The patient may sit quietly, or may talk or listen to music. The patient usually remains awake and able to remember the treatment. The entire treatment requires about an hour.
What happens after the treatment?
When the treatment is completed, the needle is removed. The patient is observed for a short time. When stable, the patient may go home. Patients often experience improved mood and reduced pain within minutes to a few hours after treatment. Driving, operation of machinery, and making legal decisions are prohibited for the rest of the day. Otherwise, the patient may resume normal activities when the effects of the medication have passed.
What side effects will I experience?
Ketamine is rapidly removed from the body. Any side effects normally resolve within a short time after completion of the treatment.
Patients often feel unsteady, clumsy, mildly intoxicated, or dizzy during and after the treatment. Some patients may experience drowsiness, anxiety, dreams, or other unusual feelings. Nausea or vomiting may occur rarely.
Ketamine infusion usually causes a brief, usually mild, increase in blood pressure and heart rate. These are monitored, and resolve quickly after treatment is stopped. The rate of treatment and dose may be adjusted, if necessary.
Ketamine does not interfere with breathing or respiratory drive, especially at low doses, and in the absence of other sedatives or narcotics. Allergies to ketamine are rare.
When ketamine is used for surgical anesthesia, it is given in much higher doses, along with other anesthetic drugs, to produce deep sedation, amnesia, muscle relaxation, and to reduce secretions. Upon awakening, a short period of agitation, confusion or hallucinations may occur. These have not been observed with use of low dose ketamine in office treatment of psychiatric conditions.
People who use ketamine illegally often consume extremely high doses daily, over months or years. Some of them eventually develop severe bladder inflammation. This uncommon adverse effect has not occurred among patients treated with ketamine for anesthesia or depression.