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Generic Name: naloxone (nah LOX own)
Brand Names: Evzio, Narcan

What is naloxone?

Naloxone is a special narcotic drug that reverses the effects of other narcotic medicines.

Naloxone is used to reverse the effects of narcotic drugs used during surgery or to treat pain.

Naloxone may also be used to treat narcotic drug overdose or to diagnose narcotic drug addiction.

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

Important information

In an emergency situation it may not be possible before you are treated to tell your caregivers about your health conditions or if you are pregnant or breast feeding. Make sure any doctor caring for you afterward knows that you have received this medication.

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Naloxone may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

If you are using any narcotic pain medication, the pain-relieving effects of the narcotic will be reversed while you are also receiving naloxone.

Drinking alcohol can increase certain side effects of naloxone.

Before receiving naloxone

You should not use this medicine if you are allergic to naloxone.

If possible before you receive naloxone, tell your doctor if you have:

  • heart disease;

  • seizures;

  • a history of head injury or brain tumor; or

  • a history of drug or alcohol addiction.

FDA pregnancy category C. It is not known whether naloxone will harm an unborn baby. Tell your doctor if you are pregnant.

See also: Pregnancy and breastfeeding warnings (in more detail)

It is not known whether naloxone passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How is naloxone given?

Naloxone is injected into a muscle or under the skin, or into a vein through an IV. You will receive this injection in a clinic or hospital setting.

Your breathing, blood pressure, oxygen levels, kidney function, and other vital signs will be watched closely while you are receiving naloxone. This will help your doctor determine how long to treat you with this medication.

What happens if I miss a dose?

Because you will receive naloxone in a clinical setting, you are not likely to miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include seizure (convulsions), feeling light-headed, or fainting.

What should I avoid while using naloxone?

Naloxone may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol can increase certain side effects of naloxone.

Naloxone side effects

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

Tell your caregivers right away if you have:

  • agitation;

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

  • slow heart rate, weak or shallow breathing;

  • anxiety, sweating, pale skin, severe shortness of breath, wheezing, gasping for breath, cough with foamy mucus, chest pain, fast or uneven heart rate; or

  • dangerously high blood pressure--severe headache, blurred vision, pounding in your neck or ears, nosebleed, anxiety, confusion, severe chest pain, shortness of breath, irregular heartbeats, seizure.

If you are being treated for narcotic drug addiction, naloxone may cause withdrawal symptoms such as:

  • nausea, vomiting, diarrhea, stomach pain;

  • fever, sweating, body aches, weakness, runny nose;

  • feeling nervous, restless, or irritable;

  • goosebumps, shivering; or

  • pounding heartbeats.

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.

See also: Side effects (in more detail)

Naloxone dosing information

Usual Adult Dose for Opioid Overdose:

0.4 to 2 mg/dose IV/IM/subcutaneously. May repeat every 2 to 3 minutes as needed. Therapy may need to be reassessed if no response is seen after a cumulative dose of 10 mg.

Continuous infusion: 0.005 mg/kg loading dose followed by an infusion of 0.0025 mg/kg/hr.

Usual Pediatric Dose of Naloxone for Opioid Overdose:

Infants, Children, and Adolescents:
Opioid intoxication (full reversal):
IV (preferred) or Intraosseous (IO): Note: May be administered IM, Subcutaneous, or endotracheal tube (ET), but onset of action may be delayed, especially if patient has poor perfusion; ET preferred if IV or IO route not available; doses may need to be repeated.

Infants and Children less than or equal to 5 years or less than or equal to 20 kg: 0.1 mg/kg/dose; repeat every 2 to 3 minutes if needed; may need to repeat doses every 20 to 60 minutes.

Children greater than 5 years or greater than 20 kg and Adolescents: 2 mg/dose; if no response, repeat every 2 to 3 minutes; may need to repeat doses every 20 to 60 minutes.

ET: Optimal endotracheal dose unknown; current expert recommendations are 2 to 3 times the IV dose.

Manufacturer recommendations: IV (preferred), IM, Subcutaneous:
Initial: 0.01 mg/kg/dose; if no response, a subsequent dose of 0.1 mg/kg may be given
Note: If using IM or Subcutaneous route, dose should be given in divided doses.

Continuous IV infusion:
Children: If continuous infusion is required, calculate the initial dosage/hour based on the effective intermittent dose used and duration of adequate response seen; titrate dose; a range of 2.5 to 160 mcg/kg/hour has been reported; taper continuous infusion gradually to avoid relapse.

Respiratory depression [therapeutic opioid use (e.g., postanesthesia)]:
PALS Guidelines, 2010: IV: 0.001 to 0.005 mg/kg/dose; titrate to effect
Manufacturer recommendations: Initial: 0.005 to 0.01 mg/kg; repeat every 2 to 3 minutes as needed based on response.

Opioid-induced pruritus:
Children and Adolescents: Limited data available

What other drugs will affect naloxone?

If you are using any narcotic pain medicine, the pain-relieving effects of the narcotic will be reversed while you are also receiving naloxone.

Other drugs may interact with naloxone, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about naloxone.
  • Remember, keep this and all other medicines out of the reach of children, never share naloxone with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2015 Cerner Multum, Inc. Version: 3.03. Revision Date: 2014-08-16, 8:20:04 AM.