You should not be treated with ketamine if you have untreated or uncontrolled hypertension (high blood pressure).
Tell your caregivers at once if you have serious side effects within 24 hours after you receive ketamine, including severe confusion, hallucinations, unusual thoughts, or extreme fear.
Before taking this medicine
You should not receive ketamine if you are allergic to it, or if you have untreated or uncontrolled hypertension (high blood pressure).
Tell your doctor if you have ever had:
heart disease;
high blood pressure;
alcoholism; or
if you drink large amounts of alcohol.
Ketamine may be harmful to an unborn baby. Tell your doctor if you are pregnant.
Anesthesia medicine may affect brain development in a child under 3, or an unborn baby whose mother receives  ketamine during late pregnancy. These effects may be more likely when the anesthesia is used for 3 hours or longer, or used for repeated procedures. Effects on brain development could cause learning or behavior problems later in life.
Negative brain effects from anesthesia have been seen in animal studies. However, studies in human children receiving single short uses of anesthesia have not shown a likely effect on behavior or learning. More research is needed.
In some cases, your doctor may decide to postpone a surgery or procedure based on these risks. Treatment may not be delayed in the case of life-threatening conditions, medical emergencies, or surgery needed to correct certain birth defects.
Ask your doctor for information about all medicines that will be used during your surgery or procedure. Also ask how long the procedure will last.
It may not be safe to breast-feed shortly after receiving this medicine. Ask your doctor about any risk.
How is ketamine given?
Ketamine is injected into a muscle, or as an infusion into a vein. You will receive this injection in a clinic or hospital setting.
Your breathing, blood pressure, heart function, and other vital signs will be watched closely while you are receiving ketamine.
You may feel strange or slightly confused when you first come out of anesthesia. Tell your caregivers if these feelings are severe or unpleasant.
What happens if I miss a dose?
Since ketamine is usually given for anesthesia, you are not likely to be on a dosing schedule.
What happens if I overdose?
Since ketamine is given by a healthcare professional in a medical setting, an overdose is unlikely to occur. Your vital signs will be closely watched while you are under anesthesia to make sure the medication is not causing any harmful effects.
