IV Ketamine

What is ketamine?

Ketamine is a medicine that was developed as an anesthetic to block pain during surgery. It has been used this way for the last 50 years and is safe and effective. It 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 responded well 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 completed at this time. Compared to another drug or no drug at all, ketamine reduces the following in the short-term:

  • Reduces depressive symptoms
  • Reduces thoughts of suicide

How does ketamine work to improve depression?

Ketamine is thought to impact neurotransmitters in the brain including glutamate. Research suggests that these changes improve mood and thinking, which are impacted by depression.

Who is eligible for ketamine treatment?

To be eligible for ketamine treatment you must:

  • Have a primary diagnosis of moderate to severe depression
  • Have tried other forms of treatment (medications, psychotherapy, brain stimulation), but they have not helped you
  • Have a referral from your doctor
  • You are not eligible for ketamine treatment if you have an active substance use disorder or have symptoms of psychosis.

Who should not get ketamine?

You should not get ketamine if:

  • You suffer from psychotic disorders or have psychotic symptoms
  • You have an active substance use disorder or are on maintenance treatment for a substance use disorder
  • You have high blood pressure that is not well controlled or other serious medical conditions
  • You have symptoms from a traumatic brain injury
  • You have a hypersensitivity to the ketamine drug
  • Do I have to pay for this treatment?
  • No, there is no cost to you to receive this treatment, which includes 6 sessions.

How is ketamine given?

Our program uses intravenous ketamine (through an 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 the other forms of ketamine for maintenance therapy.

What dose of ketamine will be used?

The most common dose is 0.5 mg/kg infused over 40 minutes. Your psychiatrist will decide if you need a different dose.

How many sessions of treatment will I need?

You will receive your IV ketamine treatment 2 times per week for 3 weeks. In total, you will receive 6 treatments over 3 weeks.

How effective is the treatment?

About one third of patients have significant improvement (their depressive symptoms largely go away) by the end of one series of IV treatments. About one third of patients do not improve with ketamine treatment. The other third usually have some improvement.

How quickly does IV ketamine treatment begin to work?

You may feel the effects within a few hours to 24 hours of a single treatment, however it often takes a few days to feel better. It has been shown that benefits improve with repeated treatments.

How long do the effects of repeated doses of ketamine last?

We do not know this with certainty. Here is what research has shown so far for patients who have significant improvement:

  • After a single treatment of IV ketamine, effects can appear within a few hours, peak at 24 hours after the treatment, and often remain for at least 1 week.
  • After repeated treatments, the effects can be longer. People remain well between several days to several months. Some people remain well for longer periods of time.
  • People could maintain the benefits with more doses of ketamine or with other treatments (for example other medications, psychotherapy, or neurostimulation). Please note that we don’t currently have enough research about the best ways to maintain benefits following one series of IV treatments. At this time, booster treatments or maintenance with other forms of ketamine are not covered by OHIP.

What are the side effects of ketamine and what should I do if I have them?

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 between 4 to 24 hours afterwards.

The most common short term side effects of ketamine used for this purpose include:

  • Nausea
  • Vomiting
  • Dizziness
  • Headache
  • Blurred vision
  • Anxiety
  • A sense of dissociation (feeling disconnected from yourself or surroundings)
  • Increased blood pressure and increased heart rate

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 have side effects more than 24 hours after your treatment, or if the side effects are getting worse:

  • Contact our office at 416-864-5418 during business hours, or
  • Go to your nearest emergency department

Are there any long-term side effects?

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.

Can I continue taking my antidepressant while getting ketamine treatment?

Ketamine treatment is safe to receive when taking most antidepressants. Some studies suggest that ketamine treatment may not work as well if you are also taking benzodiazepines and NMDA receptor antagonists. Your psychiatrist will review your medications to decide if ketamine treatment is right for you.

Do I need a referral for ketamine treatment?

Yes, you need a referral from your regular doctor. Our program does not provide long-term follow-up after completion of the IV ketamine treatments. You will need to follow-up with your doctor for ongoing care.

For more information:

Talk to your doctor if you want more information about ketamine IV treatments.