How Long Does Ketamine Stay in Your System?

2022-07-27T21:58:40Z

Medically reviewed on by

Dr. Steven Harvey

Regional Medical Director Greater St. Louis

Have you ever thought about how long a medication stays in your system after you take it? Most medications must be taken regularly because they don’t last forever in our bodies. Oral antidepressants, for example, must be taken every day. 


Ketamine therapy, on the other hand, is given less often than once per day, whether it is ketamine given through an intravenous injection (IV) or in the form of esketamine nasal spray. 


The benefits of either ketamine-based treatment usually stick with you in-between doses, even though the medication is no longer in your system for much of that time.


Ketamine is eliminated from your body in two phases. The first phase is called the redistribution phase. During that phase, the amount of ketamine in your bloodstream rapidly decreases over the first 45 minutes or so. 


After that, the remaining ketamine in your body is eliminated more slowly, with a half-life of around 2.5 or 3 hours. That means half of it is eliminated in each half-life. After a few half-lives (say, 12 hours) practically all of it is gone.


Does Ketamine Show Up on Drug Test? 


Ketamine does show up on drug tests. That said, many standard drug panels do not screen for ketamine. If you’re trying to determine, “How long does ketamine stay in your system?” note that the body metabolizes it within a day or two. It’s the metabolic process that leaves behind metabolites. TTraces of these metabolites can show up on drug tests days and even months after a ketamine dose. 


Employers and other organizations who may require a drug test often use five-panel tests that can detect amphetamine, cocaine, opiates, phencyclidine (PCP), and tetrahydrocannabinol (THC). 


Others may use seven-panel drug tests that screen for the five previously mentioned drugs with the addition of benzodiazepine and barbiturates. Expanded test panels can detect eight to 12 drugs, including all of the aforementioned substances along with ecstasy (MDMA), hydrocodone (Vicodin), oxycodone (OxyContin), methadone, methaqualone, and propoxyphene. 


Ketamine doesn’t show up on this list because it’s not standard practice to test for it, even in a 12-panel drug test. However, a drug test that
does detect ketamine can be ordered. Ketamine can show up in saliva samples for up to 24 hours, in blood samples for up to 72 hours, and in urine samples for as many as two weeks. A hair test can detect ketamine for a month or longer.


If you find yourself facing a ketamine drug test and are undergoing
ketamine IV therapy or esketamine nasal spray treatment, talk to your provider. They can give you advice on how to handle the situation. 

How Long Do Ketamine Effects Last?

Ketamine side effects only last during the time the medication is in your system. The more potent side effects, such as dissociation, sedation, and nausea, usually dissipate within one to four hours. 


Drowsiness can persist for around seven to 12 hours, which is why many providers may recommend going home and resting for the remainder of the day following ketamine or esketamine therapy. If you are still feeling side effects the day after treatment, contact your provider for assistance. 


Fortunately, the positive effects ketamine and esketamine can have on depression symptoms last longer than any side effects. Ketamine IV therapy patients may receive treatment twice a week for four weeks, with maintenance doses every two to six weeks thereafter. 


Patients taking esketamine nasal spray for treatment resistant depression (TRD) or major depressive disorder with suicidal ideation (MDSI) also start out with two treatments a week for four weeks. This is often followed by one treatment a week for four additional weeks and maintenance treatments every week or two after that. 


In short, once you enter the maintenance phase of ketamine treatment, you may only have to come in one or two times a month to continue experiencing the
positive effects of ketamine


Is Ketamine Therapy for Everyone?

No. If you have a history of psychosis or have family members with a history of psychosis, ketamine therapy may not be for you. Blood vessel and cardiovascular diseases can make ketamine treatment risky, too. 


Anyone who is pregnant or breastfeeding, or is planning to breastfeed or become pregnant, should avoid taking any form of ketamine. Ask your doctor if ketamine IV therapy or esketamine nasal spray may be right for you.


Keep in mind that ketamine IV therapy is not FDA-approved for treating depression or any mental health conditions, which means insurance does not cover it. Esketamine nasal spray, on the other hand, is covered by insurance because it is FDA-approved for hard-to-treat depression, and for depression with suicidal thoughts. .


If you don’t qualify for esketamine nasal spray, transcranial magnetic stimulation (TMS) may be an option. TMS is a medication-free, FDA-cleared depression treatment that uses gentle magnetic pulses to stimulate areas of the brain. Learn more about
how long TMS therapy lasts after each treatment and how TMS works


At Greenbrook TMS, we offer TMS and
esketamine nasal spray treatment in a clean, comfortable environment. Schedule a free consultation today to find out if you may benefit from TMS or esketamine nasal spray treatment. 




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