Ketamine is a safe and effective medicine that was developed as an anesthetic to block pain during surgery, and has been used for the past 50 years. Ketamine is on the World Health Organization’s list of Essential Medications as an anesthetic.
Over the last 20 years, ketamine has been examined in smaller doses to treat psychiatric disorders, including major depressive disorder (MDD) in individuals who have not adequately responded to conventional treatments. Several short-term studies have shown that ketamine is effective for people with treatment-resistant depression; however, there are limited long-term studies examining this. Compared to another drug or no drug at all, ketamine has shown the following short-term effects:
Ketamine is thought to impact neurotransmitters in the brain including glutamate, which is the most abundant neurotransmitter in the brain. Research suggests that these changes improve mood and thinking, which are impacted by depression.
To be eligible for ketamine treatment you must:
You should not get ketamine if:
No, there is no cost to you to receive this treatment, which includes up to 4 sessions.
How is ketamine given?
Our program uses intravenous ketamine (through an intravenous (IV) line). While ketamine can also be given in other ways, giving ketamine through an IV has been studied the most and shows the most benefit so far. If you have significant improvement after one series of the IV treatment, you could be considered for use of other forms of ketamine for maintenance therapy. Our program does not cover the costs of other forms of ketamine for maintenance therapy.
The most common dose is 0.5 mg/kg infused over 40 minutes. Your psychiatrist will decide if you need a different dose.
You will receive your IV ketamine treatment 2 times per week for 2 weeks. In total, you may receive up to 4 treatments over 2 weeks.
About one third of patients show significant improvement (their depressive symptoms largely go away) by the end of IV ketamine treatment. About one third of patients do not improve with ketamine treatment. The other third usually experience some improvement.
We do not know this with certainty. Here is what research has shown so far for patients who have significant improvement:
The doses of ketamine that are used for depression are much lower than the dose used for anesthesia. This makes it quite safe, and side effects are usually limited. Any side effects usually appear within 2 hours of infusion and go away within 4 to 24 hours afterwards.
The most common short term side effects of ketamine used for this purpose include:
These symptoms appear during treatment and disappear shortly afterwards on their own. We can provide treatment for nausea during the infusion. We will monitor for these symptoms throughout the treatment.
If you experience side effects 24 hours after your treatment, or if the side effects worsen:
Short-term ketamine use (in lower doses for a limited number of treatments) has the side effects listed previously; however, there is limited literature on long-term side effects. If you are considering maintenance treatments for a longer period of time, speak to your doctor about potential side effects.
Ketamine treatment is safe to receive concurrently with most antidepressant use. Some studies suggest that ketamine treatment may not work as well if you are also taking some medications such as benzodiazepines and NMDA receptor antagonists. Your psychiatrist will review your medications to decide if ketamine treatment is right for you.
Yes, you need a referral from your regular doctor or psychiatrist. Our program does not provide long-term follow-up after the completion of IV ketamine treatments. You will need to follow-up with your doctor for ongoing care.
Talk to your doctor if you want more information about IV ketamine treatments.
IN CASE OF AN EMERGENCY
If you are having thoughts of harming yourself at any time, please call the Greater Toronto Distress Centre Helpline 416-408-HELP (4357) or visit your nearest emergency department. In this situation, please do not use the clinic voicemail or email, as it may not be possible to provide an immediate response.
