Ketamine injection: uses, how it's given, side effects
Last updated September 7, 2026.
**Ketamine injection is a dissociative general anesthetic used to prevent pain and awareness during procedures.** It blocks NMDA receptors, changing how your brain processes pain and sensory signals. You must receive it under trained medical supervision with breathing support immediately available.
What does it treat?
You may receive ketamine for anesthesia during surgery or diagnostic procedures, either alone when muscle relaxation is unnecessary or with other anesthetics. Specialists also use it off-label for conditions such as depression that has not improved with other treatments; ketamine injection is not FDA approved for psychiatric disorders. Esketamine nasal spray is a separate medication.
How do you take it?
You receive a solution through a vein or into a muscle. Labeled adult starting doses for anesthesia are 1 to 4.5 mg/kg intravenously over 60 seconds or 6.5 to 13 mg/kg intramuscularly; these are not depression dosing instructions. Your clinician adjusts additional doses, and the label gives no fixed daily ceiling. Follow your procedure team's fasting instructions. If you miss an appointment, reschedule rather than trying to replace the dose yourself. Hold further treatments and call your clinician for painful urination or yellow skin.
Side effects to know
- Common: You may experience vivid dreams, confusion while waking, nausea, vomiting, and temporary increases in blood pressure and pulse.
- Serious: Alert staff immediately for breathing difficulty, chest pain, or severe agitation so they can stop administration and treat you. After discharge, hold further treatment and seek same-day care for bloody urine, persistent bladder pain, or yellow skin or eyes.
Who should not take it?
Do not receive ketamine if you are allergic to it or its ingredients, or if a substantial blood pressure rise would seriously endanger you. Discuss heart disease, high blood pressure, increased pressure inside your skull, liver problems, and substance use history first. Review opioids, benzodiazepines, sleep medicines, stimulants, theophylline, and aminophylline with your clinician. Avoid alcohol around treatment. Labeling advises avoiding use during pregnancy, labor, and delivery; during breastfeeding, treatment should be limited to anesthesia with an individualized feeding and infant monitoring plan.
When is it an emergency?
Overdose can cause profound sleepiness, slow or stopped breathing, and abnormal heart rate or blood pressure. Call Poison Control at 1-800-222-1222 for suspected overdose; call 911 for collapse, inability to wake, or breathing trouble. Call 911 for throat swelling, chest pain, or a seizure. Hives with breathing trouble can signal anaphylaxis.
What a Pymander AI doctor consult looks like
Illustrative example, not a real member's messages.
Common questions
What is the maximum dose?
The anesthesia label has no fixed daily maximum. Your clinician selects doses using your weight, response, and other anesthetics. Never calculate or inject your own dose.
Can I drink alcohol?
Avoid alcohol around treatment. Combining it with ketamine can suppress breathing and cause profound sedation. Ask your treatment team when you can resume drinking.
What if I am pregnant or breastfeeding?
Tell your clinician before treatment. Labeling advises avoiding ketamine during pregnancy, labor, and delivery. Ketamine enters breast milk, and labeled use during breastfeeding should be limited to anesthesia. Your team should arrange monitoring for infant sleepiness, breathing suppression, stiffness, or spasms.
Can I eat before my injection?
Follow your team's specific fasting instructions. Vomiting and inhaling stomach contents can occur during anesthesia. Tell staff if you ate or drank outside those instructions.
How do I recognize an overdose?
Warning signs include inability to wake and slow or stopped breathing. Call 911 for these symptoms or collapse. For suspected overdose without emergency symptoms, call Poison Control at 1-800-222-1222 immediately.
Which medicines interact with ketamine?
Opioids, benzodiazepines, and other sedatives increase breathing and sedation risks. Theophylline and aminophylline increase seizure risk. Stimulants can intensify cardiovascular effects. Give your team your complete medication list before treatment.