Ketamine

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• IXABEPILONE/KETAMINE
• KETAMINE/SODIUM OXYBATE

This is not a complete list of Ketaminedrug interactions. Ask your doctor or pharmacist for more information.

Ketamine is available in the following forms:

• Injectable Solution
• Prefilled Syringe

Ketamine is an anesthetic medication.

Ketamine is used to put you to sleep for surgery and to prevent pain and discomfort during certain medical tests or procedures.

Ketamine may also be used for purposes not listed in this medication guide.

You should not receive ketamine if you have untreated or uncontrolled hypertension (high blood pressure).

Do not receive this medicine if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

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.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers at once if you have any of these serious side effects within 24 hours after you receive ketamine: severe confusion, hallucinations, unusual thoughts, or extreme fear.

Call your doctor at once if you have:

• a light-headed feeling, like you might pass out;

• slow heart rate, weak or shallow breathing;

• pain or burning when you urinate; or

• jerky muscle movements that may look like convulsions.

Common side effects may include:

• dream-like feeling;

• blurred vision, double vision;

• mild dizziness, drowsiness;

• nausea, vomiting, loss of appetite; or

• sleep problems (insomnia).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Usual Adult Dose for Anesthesia:

IV:
-Induction: 1 to 4.5 mg/kg IV; alternatively, 1 to 2 mg/kg IV at a rate of 0.5 mg/kg/min; (2 mg/kg dose provides 5 to 10 minutes of surgical anesthesia within 30 seconds)
-Maintenance: The maintenance dose should be adjusted according to the patient's anesthetic needs and whether an additional anesthetic is employed. Increments of one-half to the full induction dose may be repeated as needed for maintenance of anesthesia.

IM:
-Induction: 6.5 to 13 mg/kg IV; (9 to 13 mg/kg IV provides 12 to 25 minutes of surgical anesthesia)
-Maintenance: The maintenance dose should be adjusted according to the patient's anesthetic needs and whether an additional anesthetic is employed. Increments of one-half to the full induction dose may be repeated as needed for maintenance of anesthesia.

Comments:
-This drug should be administered slowly over a period of 60 seconds (more rapid administration may result in respiratory depression and enhanced pressor response).
-The larger the total dose, the longer will be complete recovery.
-Because of rapid induction following the initial IV injection, the patient should be in a supported position during administration.

Usual Pediatric Dose for Anesthesia:

16 years and older: See adult dosing

• Tell all of your health care providers that you take this medicine. This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert for 1 full day after getting ketamine and until the effects of this medicine have worn off.
• Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
• Have your blood pressure checked often. Talk with your doctor.
• You will need to have heart function tests while taking ketamine. Talk with the doctor.
• Mental problems have happened with this medicine as ketamine wears off. These problems may range from pleasant, dream-like states to hallucinations, change in how you act, or not thinking clearly or with logic. Most of the time, these problems last up to 2 hours but may last up to 24 hours after using this medicine. Be sure to have an adult you can trust watch and help you for up to 24 hours after you get ketamine. Talk with your doctor.
• If you are 65 or older, use this medicine with care. You could have more side effects.
• Studies in young animals and children have shown that frequent or long-term use of anesthesia drugs or drugs used for sleep in children younger than 3 years of age may lead to long-term brain problems. This may also happen in unborn babies if the mother uses ketamine during the third trimester of pregnancy. Talk with the doctor.
• Use with care in children. Talk with the doctor.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Produces a cataleptic-like state in which the patient is dissociated from the surrounding environment by direct action on the cortex and limbic system. Ketamine is a noncompetitive NMDA receptor antagonist that blocks glutamate. Low (subanesthetic) doses produce analgesia, and modulate central sensitization, hyperalgesia and opioid tolerance. Reduces polysynaptic spinal reflexes.

Distribution

Vdss: 2.4 L/kg (Wagner 1997)

Metabolism

Hepatic via N-dealkylation (metabolite I [norketamine]), hydroxylation of the cyclohexone ring (metabolites III and IV), conjugation with glucuronic acid and dehydration of the hydroxylated metabolites to form the cyclohexene derivative (metabolite II); metabolite I (norketamine) is 33% as potent as parent compound. When administered orally, norketamine concentrations are higher compared to other routes of administration due to extensive first-pass metabolism in the liver (Blonk 2010; Soto 2012).

Excretion

Urine (91%); feces (3%) (Ghoneim 1977)

IV: Anesthetic effect: Within 30 seconds

IM: Anesthetic effect: 3 to 4 minutes; Analgesia: Within 10 to 15 minutes

Intranasal: Analgesic effect: Within 10 minutes (Carr 2004); Sedation: Children 2 to 6 years: 5 to 8 minutes (Bahetwar 2011)

Oral: Analgesia: Within 30 minutes; Sedation: Children 2 to 8 years (Turhanoglu 2003):

4 mg/kg/dose: 12.9 ± 1.9 minutes

6 mg/kg/dose: 10.4 ± 2.9 minutes

8 mg/kg/dose: 9.5 ± 1.9 minutes

Time to Peak

Plasma:

IM: 5 to 30 minutes (Clements 1982)

Intranasal: 10 to 14 minutes (Huge 2010); Children 2 to 9 years: ~20 minutes (Malinovsky 1996)

Oral: ~30 minutes (Soto 2012)

Rectal: Children 2 to 9 years: ~45 minutes (Malinovsky 1996)

Safety and efficacy have not been established in patients younger than 16 years.

Consult WARNINGS section for additional precautions.