Patient care

Ketamine in the ER

Ketamine has some fairly unique characteristics that make it an exceptionally useful tool for those of us working in emergency medicine.


Many ER doctors view ketamine as a bit of a wonder drug, and I am certainly no exception. The first time I used it was in the military on one of my Ranger Medics in 2014 after he sustained a significant hand trauma. The injury was severe, so we went straight to an 800 mcg fentanyl lollipop, and then another. This is a pretty strong pain dose in someone who hasn’t built a tolerance to narcotics, but it didn’t touch him. Like pretty much any Army Ranger, my soldier was well-trained and tough, but I could tell he was doing his best to hold it together in front of the other guys.

Not being comfortable with giving more opioids in a limited-resource setting, we quickly wiped the mud and sweat from his arm, started an IV and gave 10 mg of ketamine, a very low dose for his size, knowing we could easily give more through the IV if needed. Just the one dose took effect in less than a minute and relieved both his pain and anxiety without any level of concerning sedation. I became a believer in ketamine use in the ER.

Ketamine has some fairly unique characteristics that make it an exceptionally useful tool for those of us working in emergency medicine. I can use it to treat pain and the anxiety of not being able to breathe while simultaneously helping open the smaller airways in someone having a severe asthma attack, chemically sedate a patient who is a danger to themselves or others, safely render a very sick patient unconscious so I can put a breathing tube down their throat and hook them up to a ventilator, and more.

Ketamine is also making huge waves in the mental health literature. Study after study keeps supporting its use to treat, among other conditions, depression, anxiety, PTSD and suicidality.

What ketamine is

As ketamine is such a unique drug, its mechanism of action has been the source of a large number of scientific articles. A 2021 paper looking at ketamine’s potential in the treatment of depression drew on work from 89 other published scientific articles to break down ketamine’s effects at the neurotransmitter and receptor level in the brain. The following information was found regarding its use:

1) NMDA antagonist — like its dangerous, unstable cousin PCP, ketamine’s blockade at this receptor is responsible for its amnestic and psychosensory effects.

2) Opioid agonist — Ketamine binds to the mu, kappa and delta opioid receptors to block pain in a similar manner to traditional narcotic medications like morphine.

3) Stimulates noradrenergic neurons and inhibits the uptake of catecholamines — this leads to an increase of the potent neurotransmitter’s norepinephrine, serotonin and dopamine. Many of the commonly prescribed antidepressants such as Prozac act to increase the circulating amount of either one or multiple of these same neurotransmitters. Norepinephrine is also used as a first-line therapy in the ER and ICU to increase blood pressure.

4) Other benefits include sodium channel effects for localized pain control, inhibiting neuronal potassium channels which may be neuroprotective, GABA effects which help decrease anxiety and mTOR stimulation, which may have long-term antidepressant effects through protection of neurotrophic growth factors.

How I use it in the ER

Ketamine is essentially a dissociative anesthetic, able to temporarily separate you from reality while blocking pain. This combo of traits can be really useful in the ER. We do commonly use a variety of other effective amnestic (memory-wiping) medications in the ER for similar purposes, the most notable being Propofol. Versed, Ativan, Valium and Xanax are fairly well-recognized as anxiety meds but also provide amnesia at higher doses.

We do have other effective medications to block pain, such as fentanyl and oxycodone, which are also now well-recognized as we are still trying to work our way out of the opioid epidemic. Ketamine is unique among pain and sedative meds in that it both separates one from the memory of the painful procedure and actually blocks the pain at the receptor level.

Ketamine has some other unique characteristics as well. It helps support the circulatory hemodynamics, meaning it will cause a mild increase in blood pressure and heart rate. This is exceptionally useful in the care of our sickest patients when we need to intubate them. The other medications from both the pain blocking and amnestic groups generally do the opposite and decrease the circulatory drive, lowering the blood pressure and the profusion to vital organs.

Finally, ketamine does not decrease the respiratory drive. Respiratory depression (simply not taking breaths) is the main reason people die during opioid overdoses. This is important for us in the ER, as we sometimes have patients who pose a significant violent threat to themselves and our staff, and we need to calm them down, but would very much prefer they keep breathing on their own. Ketamine is our most rapid onset intramuscular medication take-down option.

As a full-time, practicing emergency physician at a large academic level one trauma center, I am very familiar with using ketamine to help treat my patients in all of the above listed ways. I will also use it in very low doses occasionally to strictly control moderate to severe pain when I want to avoid narcotics. Allergies or prior opioid addiction would be reasons for this.

I’ve also found it very useful in similar low doses to help with the anxiety of not being able to breathe while pharmacologically helping open the distal airways in severe asthma attacks. The huge range of positives said, there are potential drawbacks, reasons and scenarios that an ER physician will choose not to use ketamine based on both hospital policy and the individual patient they are treating.

‘A complex and fascinating neuroactive chemical’

Ketamine is a complex and fascinating neuroactive chemical with research supporting its ability to facilitate both medical and psychiatric care in a variety of ways. Its effects are dose-dependent, ranging from pain control, anxiety reduction and mild euphoria in lower doses to completely detaching a user from their physical reality at higher doses. Unlike other potent amnestic and analgesic medications, ketamine tends not to decrease the drive to breathe and mildly supports circulation, making it pharmacologically safer in relation to its potential power of effect.

This said, I am absolutely against recreational use of ketamine for two reasons – source and surroundings. It is all too common we see dangerous overdoses in the ER from people who obtained street pharmaceuticals that contain a different substance than what they thought they were buying. The setting is potentially even more terrifying. In any significant dose, ketamine will make a user unable to defend themselves in any manner. The key to experiencing ketamine in the most beneficial way is to leave it to the professionals.

Editor’s note: The views expressed in this article are the author’s own and do not necessarily represent the views of The DO or the AOA.

Related reading:

The pros and cons of staying involved in medicine after retiring

The state of DO-MD relations: This emergency medicine physician has a unique take


  1. Gary Glaze DO

    Dr Ballard has provided a very concise and informative article concerning Ketamine use. However, 2 important concerns with ketamine are secretion production and vivid dreams. Ketamine will increase oral secretions and can lead to laryngospasm. This must be considered when using ketamine for sedation, especially in areas where emergency intubation is difficult to perform. Remember Elijah McClain who died from ketamine “overdose” at the hands of paramedics in an effort to control “excited delirium”. The other issue with ketamine is “vivid dreams”, aka. night terrors. Ketamine can induce a dream state at higher doses and while 80% of patients describe the dream experience as pleasurable, 20% find the experience terrifying. Using Robinul to control secretions and Versed to help with the dreams are great adjuncts to ketamine use. Ketamine is a great drug that I use as an anesthesiologist. Being prepared to mitigate any side effects is important for this and any other medication that we use.

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