Ketamine is a very unique medication. It has multiple effects and uses. This characteristic makes the effects of Ketamine very patient specific. No specific dose works the same for everyone. But, there are some advantages to giving Ketamine by IV infusion that is true for all patients.
One advantage of an IV infusion is best explained by understanding the concept of bioavailability. This refers to the degree that a drug is available in the patient's circulation for the body to use. The bioavailability of a drug can be very different depending on the route of administration. Ketamine may be given by several routes that result in different levels of bioavailability. The chart below shows the level of bioavailability associated with the different routes that ketamine can be given.
Route of Administration and Ketamine Bioavailability
Route Bioavailability
Intravenous (IV infusion): 100%
Intramuscular Injection: 93%
Subcutaneous Injection: varies
Epidural: 77%
Intranasal: varies 8-50%
Sublingual: 30%
Rectal 11-30%
Oral: 16-29%
Topical: small amount/exact unknown
As you can see, the greatest bioavailability is achieved by the IV route. 100% of Ketamine given by IV is available for the body to use. Ketamine can be given as an IV-push, where the entire dose is given IV all at once. This is not recommended because of the potential unwanted side effects seen when a large dose is administered in a short period. However, when ketamine is administered by IV infusion we are able to deliver the total high doses needed, but we deliver it slowly over hours as a low rate controlled infusion.
As a low rate IV infusion dose control is achieved by using an IV infusion-pump. The IV infusion-pump allows exact control of dose rate. This way patients can safely receive ketamine over hours at the exact infusion rate and total dose needed. Longer Infusion times also allow for continuous vital sign safety monitoring. During the IV infusion, an IV infusion-pump can be easily adjusted. This allows us to gradually increased or decreased dosing as appropriate to reach the desired therapeutic levels. Another advantage is that with continuous vital sign monitoring any developing side effects can be identified and immediately managed. Most importantly if needed an IV infusion can be stopped immediately. With these low rate-controlled infusions the effects of Ketamine disappear rapidly when the infusion is terminated.
All of these factors make receiving Ketamine by IV infusion the most efficacious and safe route compared to others. In sum, we give Ketamine by IV infusion because that is the safest and best way to achieve our best results.
Check back soon. Next we will talk about how Ketamine works and its very unique effect on the neuroplasticity of neuron connections in the brain.
I am so glad that people are finally starting to speak and write about Ketamine therapy. For years, I have been battling depression demons and it has not been easy. A friend of mine recommended ketamine therapy so I gave it a try. So far, it has helped me and I am much better for it. I hope others will find ways to combat their own demons.