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Ketamine Side Effects

Medically reviewed by Last updated on Oct 6, 2023.

Applies to ketamine: injection solution.

Serious side effects of Ketamine

Along with its needed effects, ketamine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking ketamine:

Incidence not known

  • Bloody or cloudy urine
  • bluish lips or skin
  • blurred or change in vision
  • burning while urinating
  • chest pain, discomfort, or tightness
  • confusion
  • confusion as to time, place, or person
  • cough
  • difficult, burning, or painful urination
  • difficulty with swallowing
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fainting
  • fast, slow, or irregular heartbeat
  • frequent urge to urinate
  • hives, itching, skin rash
  • holding false beliefs that cannot be changed by fact
  • irregular, fast or slow, or shallow breathing
  • loss of vision
  • not breathing
  • pale or blue lips, fingernails, or skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • seeing, hearing, or feeling things that are not there
  • seizures
  • sweating
  • trouble breathing
  • unusual excitement, nervousness, or restlessness
  • unusual tiredness or weakness

Other side effects of Ketamine

Some side effects of ketamine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

  • Double vision
  • dream-like state
  • flushing or redness of the skin
  • loss of appetite
  • nausea
  • pain at the injection site
  • seeing double
  • uncontrolled eye movements
  • unusually warm skin
  • vomiting
  • weight loss

For Healthcare Professionals

Applies to ketamine: compounding powder, injectable solution, intravenous solution.


Common (1% to 10%): Blood pressure increased, heart rate increased, increased pulse rate

Uncommon (0.1% to 1%): Bradycardia, arrhythmia, hypotension

Frequency not reported: Arrhythmia[Ref]


Common (1% to 10%): Respiratory rate increased

Uncommon (0.1% to 1%): Respiratory depression, laryngospasm

Rare (less than 0.1%): Obstructive airway disorder, apnea[Ref]


Common (1% to 10%): Nystagmus, diplopia

Frequency not reported: Intraocular pressure increased[Ref]


Common (1% to 10%): Nausea, vomiting, anorexia

Rare (less than 0.1%): Salivary hypersecretion[Ref]


Common (1% to 10%): Hypertonia, tonic clonic movements[Ref]


Uncommon (0.1% to 1%): Injection site pain, injection site rash[Ref]


Common (1% to 10%): Erythema, morbilliform rash[Ref]


Common (1% to 10%): Hallucination, abnormal dreams, nightmare, confusion, agitation, abnormal behavior

Uncommon (0.1% to 1%): Anxiety

Rare (less than 0.1%): Delirium, flashback, dysphoria, insomnia, disorientation

Frequency not reported: Psychotic episodes[Ref]


Rare (less than 0.1%): Cystitis, hemorrhagic cystitis[Ref]


Frequency not reported: Liver function test abnormal[Ref]


Common (1% to 10%): Anaphylactic reaction[Ref]


1. Cerner Multum, Inc. UK Summary of Product Characteristics.

2. Cerner Multum, Inc. Australian Product Information.

3. Product Information. Ketalar (ketamine). JHP Pharmaceuticals. 2009.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.